Correct Trans and diff fluid for a YJ
07-30-2004, 11:55 PM
#51
Guest
Posts: n/a
Re: Correct Trans and diff fluid for a YJ
The "cold" rating of an oil (i.e., "70w-x") is an oils actual petroleum
viscosity, the other rating (i,e., "Xw-90") is its "petroleum equivalent"
rating at average operating temp and is simply a rating based upon the
effectiveness of its additives.
Thus, a 75w-90 is actually a thin 75 weight oil when cold, but becomes the
"equivalent" of a 90 weight oil when hot. Same with multi-vis motor oil.
Most wear and shifting problems occur when a unit is cold. Thus, because of
it's superior flowing capabilities, a lighter oil is best under that
condition. However, under higher temps and load a higher viscosity (90w) is
better. To get the best of both worlds petroleum engineers start with a
light weight base stock, then introduce additives that increase its
capabilities under heat and pressure.
The sulphur content of gear oils adds a complication: higher sulphur content
(i.e., GL5) in a gear oil is an advantage when the oil is under pressure,
such as when it's squeezed between a ring and pinion. Unfortunately, that
very advantage becomes a disadvantage re: synchronizer rings, which must
have enough friction capability to stop spinning gears to avoid gear clash.
High sulphur content oils compromise that function. Thus, engineers specify
lower sulphur (GL3 or CL4) oil in transmissions to keep cold synchros happy.
This stuff is really easy to see. Compare a bit of 75w-90 gear oil to
straight 90w and it's easily apparent which is the lighter oil. You can also
easily smell the difference between a GL5 and GL3 oil, the GL5 stuff stinks
of rotten eggs to high heaven, the GL3 stuff smells more like motor oil.
"Jerry Bransford" <jerrypb@***.net> wrote in message
news:RWBOc.4856$Xn.1978@fed1read05...
> Jerry, a 75W-90 is a 90 weight lube at normal operating temperature. The
> 75W is its' weight when cold... and the 'W' means Winter. Same with
70W-80,
> it's an 80 weight when at its normal operating temperature and a 70 weight
> when cold. :)
>
> Jerry
> --
> Jerry Bransford
> PP-ASEL N6TAY
> See the Geezer Jeep at
> http://members.***.net/jerrypb/
> "Jerry McG" <gmcgeorge.remove@frontier.net> wrote in message
> news:ceeg6u0ga7@enews3.newsguy.com...
> > > You are still confusing as ----. ;-) >
> >
> > I guess so, 'cuz we have no idea idf you're talking about me, Bransford
or
> > both of us.
> >
> > > Now you say it's 'ok' to use redline GL4, but don't do it because it's
> > supposed to be GL3 which redline doesn't make, but use redline because
it
> is
> > better. <
> >
> > Nope, you're not paying attention. DC recommnds a GL3 75w-90 (which is a
> 75
> > weight oil, not 90w.) GL3 has no sulphur additive at all, GL4 is low
> > sulphur. Redline makes 2 oils for manaul trans: 1) MTL, which is a
70w-80
> > GL4, and MT90, which is a 75w-90 GL4. MT90 would be closest to DC spec
for
> > an AX5 or 15.
> > >
> > > Oh and 'don't use 90 weight because it won't shift, but meanwhile
'you'
> > use MTL which 'is' 90 weight which is 'great stuff'.<
> >
> > Pay attention: MTL is a 70w-80, that is, a 70 weight oil. MT90 is a
> 75w-90,
> > that is, a 75 weight oil.
> >
> > > So just what the heck is it?
> >
> > How many more times do we have to spell it out?
> >
> > > 'I' know to use the GL4 'gear oil' for transmissions and to make sure
> it
> > doesn't have the limited slip additive for differentials.>
> >
> > Now we're getting somewhere, partiularly in an AX5 or 15.
> >
> > > 'I' could only find the GL4 diff fluid once when changing oil so used
> it.
> > My shifter stopped working shortly after.>
> >
> > Likely unrelated to the GL4.
> >
> > > 'I' then went and found tranny gear oil which only came in a semi
> > synthetic at my local parts store, all the 'regular' gear oil had the
> > limited slip or friction modifiers in, and now I have a sweet smooth
> shift.<
> >
> > You don't have an AX15.
> >
> >
> >
>
>
viscosity, the other rating (i,e., "Xw-90") is its "petroleum equivalent"
rating at average operating temp and is simply a rating based upon the
effectiveness of its additives.
Thus, a 75w-90 is actually a thin 75 weight oil when cold, but becomes the
"equivalent" of a 90 weight oil when hot. Same with multi-vis motor oil.
Most wear and shifting problems occur when a unit is cold. Thus, because of
it's superior flowing capabilities, a lighter oil is best under that
condition. However, under higher temps and load a higher viscosity (90w) is
better. To get the best of both worlds petroleum engineers start with a
light weight base stock, then introduce additives that increase its
capabilities under heat and pressure.
The sulphur content of gear oils adds a complication: higher sulphur content
(i.e., GL5) in a gear oil is an advantage when the oil is under pressure,
such as when it's squeezed between a ring and pinion. Unfortunately, that
very advantage becomes a disadvantage re: synchronizer rings, which must
have enough friction capability to stop spinning gears to avoid gear clash.
High sulphur content oils compromise that function. Thus, engineers specify
lower sulphur (GL3 or CL4) oil in transmissions to keep cold synchros happy.
This stuff is really easy to see. Compare a bit of 75w-90 gear oil to
straight 90w and it's easily apparent which is the lighter oil. You can also
easily smell the difference between a GL5 and GL3 oil, the GL5 stuff stinks
of rotten eggs to high heaven, the GL3 stuff smells more like motor oil.
"Jerry Bransford" <jerrypb@***.net> wrote in message
news:RWBOc.4856$Xn.1978@fed1read05...
> Jerry, a 75W-90 is a 90 weight lube at normal operating temperature. The
> 75W is its' weight when cold... and the 'W' means Winter. Same with
70W-80,
> it's an 80 weight when at its normal operating temperature and a 70 weight
> when cold. :)
>
> Jerry
> --
> Jerry Bransford
> PP-ASEL N6TAY
> See the Geezer Jeep at
> http://members.***.net/jerrypb/
> "Jerry McG" <gmcgeorge.remove@frontier.net> wrote in message
> news:ceeg6u0ga7@enews3.newsguy.com...
> > > You are still confusing as ----. ;-) >
> >
> > I guess so, 'cuz we have no idea idf you're talking about me, Bransford
or
> > both of us.
> >
> > > Now you say it's 'ok' to use redline GL4, but don't do it because it's
> > supposed to be GL3 which redline doesn't make, but use redline because
it
> is
> > better. <
> >
> > Nope, you're not paying attention. DC recommnds a GL3 75w-90 (which is a
> 75
> > weight oil, not 90w.) GL3 has no sulphur additive at all, GL4 is low
> > sulphur. Redline makes 2 oils for manaul trans: 1) MTL, which is a
70w-80
> > GL4, and MT90, which is a 75w-90 GL4. MT90 would be closest to DC spec
for
> > an AX5 or 15.
> > >
> > > Oh and 'don't use 90 weight because it won't shift, but meanwhile
'you'
> > use MTL which 'is' 90 weight which is 'great stuff'.<
> >
> > Pay attention: MTL is a 70w-80, that is, a 70 weight oil. MT90 is a
> 75w-90,
> > that is, a 75 weight oil.
> >
> > > So just what the heck is it?
> >
> > How many more times do we have to spell it out?
> >
> > > 'I' know to use the GL4 'gear oil' for transmissions and to make sure
> it
> > doesn't have the limited slip additive for differentials.>
> >
> > Now we're getting somewhere, partiularly in an AX5 or 15.
> >
> > > 'I' could only find the GL4 diff fluid once when changing oil so used
> it.
> > My shifter stopped working shortly after.>
> >
> > Likely unrelated to the GL4.
> >
> > > 'I' then went and found tranny gear oil which only came in a semi
> > synthetic at my local parts store, all the 'regular' gear oil had the
> > limited slip or friction modifiers in, and now I have a sweet smooth
> shift.<
> >
> > You don't have an AX15.
> >
> >
> >
>
>
07-30-2004, 11:55 PM
#52
Guest
Posts: n/a
Re: Correct Trans and diff fluid for a YJ
The "cold" rating of an oil (i.e., "70w-x") is an oils actual petroleum
viscosity, the other rating (i,e., "Xw-90") is its "petroleum equivalent"
rating at average operating temp and is simply a rating based upon the
effectiveness of its additives.
Thus, a 75w-90 is actually a thin 75 weight oil when cold, but becomes the
"equivalent" of a 90 weight oil when hot. Same with multi-vis motor oil.
Most wear and shifting problems occur when a unit is cold. Thus, because of
it's superior flowing capabilities, a lighter oil is best under that
condition. However, under higher temps and load a higher viscosity (90w) is
better. To get the best of both worlds petroleum engineers start with a
light weight base stock, then introduce additives that increase its
capabilities under heat and pressure.
The sulphur content of gear oils adds a complication: higher sulphur content
(i.e., GL5) in a gear oil is an advantage when the oil is under pressure,
such as when it's squeezed between a ring and pinion. Unfortunately, that
very advantage becomes a disadvantage re: synchronizer rings, which must
have enough friction capability to stop spinning gears to avoid gear clash.
High sulphur content oils compromise that function. Thus, engineers specify
lower sulphur (GL3 or CL4) oil in transmissions to keep cold synchros happy.
This stuff is really easy to see. Compare a bit of 75w-90 gear oil to
straight 90w and it's easily apparent which is the lighter oil. You can also
easily smell the difference between a GL5 and GL3 oil, the GL5 stuff stinks
of rotten eggs to high heaven, the GL3 stuff smells more like motor oil.
"Jerry Bransford" <jerrypb@***.net> wrote in message
news:RWBOc.4856$Xn.1978@fed1read05...
> Jerry, a 75W-90 is a 90 weight lube at normal operating temperature. The
> 75W is its' weight when cold... and the 'W' means Winter. Same with
70W-80,
> it's an 80 weight when at its normal operating temperature and a 70 weight
> when cold. :)
>
> Jerry
> --
> Jerry Bransford
> PP-ASEL N6TAY
> See the Geezer Jeep at
> http://members.***.net/jerrypb/
> "Jerry McG" <gmcgeorge.remove@frontier.net> wrote in message
> news:ceeg6u0ga7@enews3.newsguy.com...
> > > You are still confusing as ----. ;-) >
> >
> > I guess so, 'cuz we have no idea idf you're talking about me, Bransford
or
> > both of us.
> >
> > > Now you say it's 'ok' to use redline GL4, but don't do it because it's
> > supposed to be GL3 which redline doesn't make, but use redline because
it
> is
> > better. <
> >
> > Nope, you're not paying attention. DC recommnds a GL3 75w-90 (which is a
> 75
> > weight oil, not 90w.) GL3 has no sulphur additive at all, GL4 is low
> > sulphur. Redline makes 2 oils for manaul trans: 1) MTL, which is a
70w-80
> > GL4, and MT90, which is a 75w-90 GL4. MT90 would be closest to DC spec
for
> > an AX5 or 15.
> > >
> > > Oh and 'don't use 90 weight because it won't shift, but meanwhile
'you'
> > use MTL which 'is' 90 weight which is 'great stuff'.<
> >
> > Pay attention: MTL is a 70w-80, that is, a 70 weight oil. MT90 is a
> 75w-90,
> > that is, a 75 weight oil.
> >
> > > So just what the heck is it?
> >
> > How many more times do we have to spell it out?
> >
> > > 'I' know to use the GL4 'gear oil' for transmissions and to make sure
> it
> > doesn't have the limited slip additive for differentials.>
> >
> > Now we're getting somewhere, partiularly in an AX5 or 15.
> >
> > > 'I' could only find the GL4 diff fluid once when changing oil so used
> it.
> > My shifter stopped working shortly after.>
> >
> > Likely unrelated to the GL4.
> >
> > > 'I' then went and found tranny gear oil which only came in a semi
> > synthetic at my local parts store, all the 'regular' gear oil had the
> > limited slip or friction modifiers in, and now I have a sweet smooth
> shift.<
> >
> > You don't have an AX15.
> >
> >
> >
>
>
viscosity, the other rating (i,e., "Xw-90") is its "petroleum equivalent"
rating at average operating temp and is simply a rating based upon the
effectiveness of its additives.
Thus, a 75w-90 is actually a thin 75 weight oil when cold, but becomes the
"equivalent" of a 90 weight oil when hot. Same with multi-vis motor oil.
Most wear and shifting problems occur when a unit is cold. Thus, because of
it's superior flowing capabilities, a lighter oil is best under that
condition. However, under higher temps and load a higher viscosity (90w) is
better. To get the best of both worlds petroleum engineers start with a
light weight base stock, then introduce additives that increase its
capabilities under heat and pressure.
The sulphur content of gear oils adds a complication: higher sulphur content
(i.e., GL5) in a gear oil is an advantage when the oil is under pressure,
such as when it's squeezed between a ring and pinion. Unfortunately, that
very advantage becomes a disadvantage re: synchronizer rings, which must
have enough friction capability to stop spinning gears to avoid gear clash.
High sulphur content oils compromise that function. Thus, engineers specify
lower sulphur (GL3 or CL4) oil in transmissions to keep cold synchros happy.
This stuff is really easy to see. Compare a bit of 75w-90 gear oil to
straight 90w and it's easily apparent which is the lighter oil. You can also
easily smell the difference between a GL5 and GL3 oil, the GL5 stuff stinks
of rotten eggs to high heaven, the GL3 stuff smells more like motor oil.
"Jerry Bransford" <jerrypb@***.net> wrote in message
news:RWBOc.4856$Xn.1978@fed1read05...
> Jerry, a 75W-90 is a 90 weight lube at normal operating temperature. The
> 75W is its' weight when cold... and the 'W' means Winter. Same with
70W-80,
> it's an 80 weight when at its normal operating temperature and a 70 weight
> when cold. :)
>
> Jerry
> --
> Jerry Bransford
> PP-ASEL N6TAY
> See the Geezer Jeep at
> http://members.***.net/jerrypb/
> "Jerry McG" <gmcgeorge.remove@frontier.net> wrote in message
> news:ceeg6u0ga7@enews3.newsguy.com...
> > > You are still confusing as ----. ;-) >
> >
> > I guess so, 'cuz we have no idea idf you're talking about me, Bransford
or
> > both of us.
> >
> > > Now you say it's 'ok' to use redline GL4, but don't do it because it's
> > supposed to be GL3 which redline doesn't make, but use redline because
it
> is
> > better. <
> >
> > Nope, you're not paying attention. DC recommnds a GL3 75w-90 (which is a
> 75
> > weight oil, not 90w.) GL3 has no sulphur additive at all, GL4 is low
> > sulphur. Redline makes 2 oils for manaul trans: 1) MTL, which is a
70w-80
> > GL4, and MT90, which is a 75w-90 GL4. MT90 would be closest to DC spec
for
> > an AX5 or 15.
> > >
> > > Oh and 'don't use 90 weight because it won't shift, but meanwhile
'you'
> > use MTL which 'is' 90 weight which is 'great stuff'.<
> >
> > Pay attention: MTL is a 70w-80, that is, a 70 weight oil. MT90 is a
> 75w-90,
> > that is, a 75 weight oil.
> >
> > > So just what the heck is it?
> >
> > How many more times do we have to spell it out?
> >
> > > 'I' know to use the GL4 'gear oil' for transmissions and to make sure
> it
> > doesn't have the limited slip additive for differentials.>
> >
> > Now we're getting somewhere, partiularly in an AX5 or 15.
> >
> > > 'I' could only find the GL4 diff fluid once when changing oil so used
> it.
> > My shifter stopped working shortly after.>
> >
> > Likely unrelated to the GL4.
> >
> > > 'I' then went and found tranny gear oil which only came in a semi
> > synthetic at my local parts store, all the 'regular' gear oil had the
> > limited slip or friction modifiers in, and now I have a sweet smooth
> shift.<
> >
> > You don't have an AX15.
> >
> >
> >
>
>
07-30-2004, 11:55 PM
#53
Guest
Posts: n/a
Re: Correct Trans and diff fluid for a YJ
The "cold" rating of an oil (i.e., "70w-x") is an oils actual petroleum
viscosity, the other rating (i,e., "Xw-90") is its "petroleum equivalent"
rating at average operating temp and is simply a rating based upon the
effectiveness of its additives.
Thus, a 75w-90 is actually a thin 75 weight oil when cold, but becomes the
"equivalent" of a 90 weight oil when hot. Same with multi-vis motor oil.
Most wear and shifting problems occur when a unit is cold. Thus, because of
it's superior flowing capabilities, a lighter oil is best under that
condition. However, under higher temps and load a higher viscosity (90w) is
better. To get the best of both worlds petroleum engineers start with a
light weight base stock, then introduce additives that increase its
capabilities under heat and pressure.
The sulphur content of gear oils adds a complication: higher sulphur content
(i.e., GL5) in a gear oil is an advantage when the oil is under pressure,
such as when it's squeezed between a ring and pinion. Unfortunately, that
very advantage becomes a disadvantage re: synchronizer rings, which must
have enough friction capability to stop spinning gears to avoid gear clash.
High sulphur content oils compromise that function. Thus, engineers specify
lower sulphur (GL3 or CL4) oil in transmissions to keep cold synchros happy.
This stuff is really easy to see. Compare a bit of 75w-90 gear oil to
straight 90w and it's easily apparent which is the lighter oil. You can also
easily smell the difference between a GL5 and GL3 oil, the GL5 stuff stinks
of rotten eggs to high heaven, the GL3 stuff smells more like motor oil.
"Jerry Bransford" <jerrypb@***.net> wrote in message
news:RWBOc.4856$Xn.1978@fed1read05...
> Jerry, a 75W-90 is a 90 weight lube at normal operating temperature. The
> 75W is its' weight when cold... and the 'W' means Winter. Same with
70W-80,
> it's an 80 weight when at its normal operating temperature and a 70 weight
> when cold. :)
>
> Jerry
> --
> Jerry Bransford
> PP-ASEL N6TAY
> See the Geezer Jeep at
> http://members.***.net/jerrypb/
> "Jerry McG" <gmcgeorge.remove@frontier.net> wrote in message
> news:ceeg6u0ga7@enews3.newsguy.com...
> > > You are still confusing as ----. ;-) >
> >
> > I guess so, 'cuz we have no idea idf you're talking about me, Bransford
or
> > both of us.
> >
> > > Now you say it's 'ok' to use redline GL4, but don't do it because it's
> > supposed to be GL3 which redline doesn't make, but use redline because
it
> is
> > better. <
> >
> > Nope, you're not paying attention. DC recommnds a GL3 75w-90 (which is a
> 75
> > weight oil, not 90w.) GL3 has no sulphur additive at all, GL4 is low
> > sulphur. Redline makes 2 oils for manaul trans: 1) MTL, which is a
70w-80
> > GL4, and MT90, which is a 75w-90 GL4. MT90 would be closest to DC spec
for
> > an AX5 or 15.
> > >
> > > Oh and 'don't use 90 weight because it won't shift, but meanwhile
'you'
> > use MTL which 'is' 90 weight which is 'great stuff'.<
> >
> > Pay attention: MTL is a 70w-80, that is, a 70 weight oil. MT90 is a
> 75w-90,
> > that is, a 75 weight oil.
> >
> > > So just what the heck is it?
> >
> > How many more times do we have to spell it out?
> >
> > > 'I' know to use the GL4 'gear oil' for transmissions and to make sure
> it
> > doesn't have the limited slip additive for differentials.>
> >
> > Now we're getting somewhere, partiularly in an AX5 or 15.
> >
> > > 'I' could only find the GL4 diff fluid once when changing oil so used
> it.
> > My shifter stopped working shortly after.>
> >
> > Likely unrelated to the GL4.
> >
> > > 'I' then went and found tranny gear oil which only came in a semi
> > synthetic at my local parts store, all the 'regular' gear oil had the
> > limited slip or friction modifiers in, and now I have a sweet smooth
> shift.<
> >
> > You don't have an AX15.
> >
> >
> >
>
>
viscosity, the other rating (i,e., "Xw-90") is its "petroleum equivalent"
rating at average operating temp and is simply a rating based upon the
effectiveness of its additives.
Thus, a 75w-90 is actually a thin 75 weight oil when cold, but becomes the
"equivalent" of a 90 weight oil when hot. Same with multi-vis motor oil.
Most wear and shifting problems occur when a unit is cold. Thus, because of
it's superior flowing capabilities, a lighter oil is best under that
condition. However, under higher temps and load a higher viscosity (90w) is
better. To get the best of both worlds petroleum engineers start with a
light weight base stock, then introduce additives that increase its
capabilities under heat and pressure.
The sulphur content of gear oils adds a complication: higher sulphur content
(i.e., GL5) in a gear oil is an advantage when the oil is under pressure,
such as when it's squeezed between a ring and pinion. Unfortunately, that
very advantage becomes a disadvantage re: synchronizer rings, which must
have enough friction capability to stop spinning gears to avoid gear clash.
High sulphur content oils compromise that function. Thus, engineers specify
lower sulphur (GL3 or CL4) oil in transmissions to keep cold synchros happy.
This stuff is really easy to see. Compare a bit of 75w-90 gear oil to
straight 90w and it's easily apparent which is the lighter oil. You can also
easily smell the difference between a GL5 and GL3 oil, the GL5 stuff stinks
of rotten eggs to high heaven, the GL3 stuff smells more like motor oil.
"Jerry Bransford" <jerrypb@***.net> wrote in message
news:RWBOc.4856$Xn.1978@fed1read05...
> Jerry, a 75W-90 is a 90 weight lube at normal operating temperature. The
> 75W is its' weight when cold... and the 'W' means Winter. Same with
70W-80,
> it's an 80 weight when at its normal operating temperature and a 70 weight
> when cold. :)
>
> Jerry
> --
> Jerry Bransford
> PP-ASEL N6TAY
> See the Geezer Jeep at
> http://members.***.net/jerrypb/
> "Jerry McG" <gmcgeorge.remove@frontier.net> wrote in message
> news:ceeg6u0ga7@enews3.newsguy.com...
> > > You are still confusing as ----. ;-) >
> >
> > I guess so, 'cuz we have no idea idf you're talking about me, Bransford
or
> > both of us.
> >
> > > Now you say it's 'ok' to use redline GL4, but don't do it because it's
> > supposed to be GL3 which redline doesn't make, but use redline because
it
> is
> > better. <
> >
> > Nope, you're not paying attention. DC recommnds a GL3 75w-90 (which is a
> 75
> > weight oil, not 90w.) GL3 has no sulphur additive at all, GL4 is low
> > sulphur. Redline makes 2 oils for manaul trans: 1) MTL, which is a
70w-80
> > GL4, and MT90, which is a 75w-90 GL4. MT90 would be closest to DC spec
for
> > an AX5 or 15.
> > >
> > > Oh and 'don't use 90 weight because it won't shift, but meanwhile
'you'
> > use MTL which 'is' 90 weight which is 'great stuff'.<
> >
> > Pay attention: MTL is a 70w-80, that is, a 70 weight oil. MT90 is a
> 75w-90,
> > that is, a 75 weight oil.
> >
> > > So just what the heck is it?
> >
> > How many more times do we have to spell it out?
> >
> > > 'I' know to use the GL4 'gear oil' for transmissions and to make sure
> it
> > doesn't have the limited slip additive for differentials.>
> >
> > Now we're getting somewhere, partiularly in an AX5 or 15.
> >
> > > 'I' could only find the GL4 diff fluid once when changing oil so used
> it.
> > My shifter stopped working shortly after.>
> >
> > Likely unrelated to the GL4.
> >
> > > 'I' then went and found tranny gear oil which only came in a semi
> > synthetic at my local parts store, all the 'regular' gear oil had the
> > limited slip or friction modifiers in, and now I have a sweet smooth
> shift.<
> >
> > You don't have an AX15.
> >
> >
> >
>
>
07-31-2004, 12:29 AM
#54
Guest
Posts: n/a
Re: Correct Trans and diff fluid for a YJ
Heh, one of the few things I regret doing in this life is changing the
original transmission fluid in my YJ. Coincidence or not, shortly
thereafter the second gear synchro went to hell. By the time I figured out
what had happened the original oil had been picked up by the curbside
recycling people. I got the transmission back to a semblance of normality
by putting Mobil 1 synthetic (75W90? without the limited slip modifier) in
it, but I still have to hit second at just the right rpm, or double clutch
it, to prevent grinding when shifting into that gear.
The original poster should drain his transmission fluid into a clean
container, strain it through a chamois, and pour it back in. ;o) Manual
transmissions "never" get hot enough to burn oil, and therefore the only two
likely sources of contamination are water and metal shavings. The chamois
will take care of the shavings. If the fluid is not cloudy or "milky" then
it doesn't have water in it and he is home free. I suppose you could also
use a time machine and go back far enough to buy some real GL3.
Earle
"Mike Romain" <romainm@sympatico.ca> wrote in message
news:410A80AC.47DA2446@sympatico.ca...
> You are still confusing as ----. ;-)
>
> Now you say it's 'ok' to use redline GL4, but don't do it because it's
> supposed to be GL3 which redline doesn't make, but use redline because
> it is better.
>
> Oh and 'don't use 90 weight because it won't shift, but meanwhile 'you'
> use MTL which 'is' 90 weight which is 'great stuff'.
>
> So just what the heck is it?
>
> 'I' know to use the GL4 'gear oil' for transmissions and to make sure
> it doesn't have the limited slip additive for differentials.
>
> 'I' could only find the GL4 diff fluid once when changing oil so used
> it. My shifter stopped working shortly after.
>
> 'I' then went and found tranny gear oil which only came in a semi
> synthetic at my local parts store, all the 'regular' gear oil had the
> limited slip or friction modifiers in, and now I have a sweet smooth
> shift.
>
> Mike
>
> Jerry McG wrote:
> >
> > Thanks, Jerry. If he's in a cold climate he may want to consider the
70w-80
> > fort improved cold shifting. I put the original fill of Red Line MTL in
my
> > '94 YJs AX15 at 30k miles. I changed it last year as part of the 60k
> > mainenance and noted the drain plug magnet didn't have a single flake of
> > metal on it. Great stuff!
> >
> > The owners manuals for the YJs and XJs through at least '96 also called
for
> > a 75w-90 GL5. I'm not sure when DC caught on and started using the GL3,
but
> > before that MTL was about the only thing available that would stop the
> > synchros.
> >
> > The 75w-90 GL3 sold by DC is quite pricey but works well. I put it in my
'96
> > YJs AX15 three years ago and it immediately eliminated hard cold
shifitng.
> > When I looked this a few months ago the dealer came up with two
different
> > gear oil part 3's, one recommended for the AX15, another for the NV3550.
> > They claim to have used the latter with success in the AX15, but if one
is
> > ordering this stuff might as well get the correct number.
> >
> > "Jerry Bransford" <jerrypb@***.net> wrote in message
> > news:VjjOc.4251$Xn.52@fed1read05...
> > > It calls for a 75W-90 GL-3, and there were some years when the shop
> > manuals
> > > incorrectly called for a 75W-90 GL-5. Redline's MT-90 is a 75W-90
GL-4,
> > MTL
> > > is 70W-80 GL-4. If you go with Redline, MT-90 is the correct
viscosity.
> > >
> > > Jerry
> > > --
> > > Jerry Bransford
> > > PP-ASEL N6TAY
> > > See the Geezer Jeep at
> > > http://members.***.net/jerrypb/
> > > "Jerry McG" <gmcgeorge.remove@frontier.net> wrote in message
> > > news:cecdh601c6u@enews4.newsguy.com...
> > > > Mike,
> > > >
> > > > The original manuals called for a 75w-90 GL5 oil and were corrected
by
> > > tech
> > > > service bulletin years ago. Any 80w-90, even if a lower sulphur GL4,
is
> > > far
> > > > too heavy a lubricant for an AX15 or NV3550. I believe Redline MTL
is a
> > > > 70w-80 GL4.
> > > >
> > > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > news:41096C62.7A63CE5E@sympatico.ca...
> > > > > Sorry if I got mouthy.
> > > > >
> > > > > It is still 80W90 gear oil he needs. You are mixing up terms.
> > > > >
> > > > > The GL rating has nothing to do with the weight of 80W90.
> > > > >
> > > > > Mike
> > > > >
> > > > > Jerry McG wrote:
> > > > > >
> > > > > > Mike,
> > > > > >
> > > > > > I find your description of my assitance to this guy offensive
and
> > > > > > uncharacteristic of you. What I stated is fact. The AX15 can not
> > > > tolerate
> > > > > > 80w-90 GL5 gear oil. DC recommends a special GL3 (no sulphur)
oil
> > > > available
> > > > > > from Jeep dealers. They also make a special GL3 oil for the
NV3550,
> > > > which
> > > > > > has the same issue re: GL5 oils.
> > > > > >
> > > > > > If he uses any form of GL5 gear oil he will experience difficult
to
> > > > > > impossible shifting (esp. in extreme cold) and substantial gear
> > clash.
> > > > Sorry
> > > > > > if my reply offended you, it's just the facts.
> > > > > >
> > > > > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > > > news:41092D32.D9F68E4B@sympatico.ca...
> > > > > > > He just fed you a pile of BS. Not much to thank him for.
> > > > > > >
> > > > > > > Your transfer case takes ATF and your tranny takes 80W90 GL4
'gear
> > > > oil'.
> > > > > > >
> > > > > > > Mike
> > > > > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > > > > 88 Cherokee 235 BFG AT's
> > > > > > >
> > > > > > > Brian Hubley wrote:
> > > > > > > >
> > > > > > > > Thanx Jerry
> > > > > > > >
> > > > > > > > "Jerry McG" <gmcgeorge.remove@frontier.net> wrote in message
> > > > > > > > news:ce9ko42im7@enews1.newsguy.com...
> > > > > > > > >
> > > > > > > > > "Brian Hubley" <brianhubley422@earthlink.net> wrote in
message
> > > > > > > > >
news:7hONc.16881$iK.10045@newsread2.news.atl.earth link.net...
> > > > > > > > > > I have a 91 YJ 4.0L manual with alot of miles I bought
not
> > to
> > > > long
> > > > > > ago.
> > > > > > > > I
> > > > > > > > > > would like to change the fluid in the trans and transfer
> > case.
> > > I
> > > > was
> > > > > > > > told
> > > > > > > > > 80
> > > > > > > > > > 90 for the trans, and I haven't checked on the transfer
case
> > > > yet.
> > > > > > > > Someone
> > > > > > > > > > else told me it might need automatic fluid or a
different
> > type
> > > > of
> > > > > > fluid
> > > > > > > > > for
> > > > > > > > > > the trans so I haven't done anything yet. I don't have
the
> > > > manual of
> > > > > > > > > course.
> > > > > > > > > > What should I do? Any web resource's out there?
> > > > > > > > > >
> > > > > > > > > > Would Daimler Chrysler know? I have been told they only
go
> > > back
> > > > so
> > > > > > many
> > > > > > > > > > years?
> > > > > > > > > >
> > > > > > > > > > Any suggestions would be a great help to me.
> > > > > > > > > >
> > > > > > > > > > -Brian
> > > > > > > > >
> > > > > > > > > DO NOT put 80w-90 in your transmission. It requires a GL3
or
> > GL4
> > > > (low
> > > > > > or
> > > > > > > > no
> > > > > > > > > sulphur) gear oil, other wise the synchros will not be
able to
> > > > > > function
> > > > > > > > > properly and you'll get serious cold gear clash when
shifting.
> > > DC
> > > > has
> > > > > > a
> > > > > > > > > special gear oil for AX15s, plus another for the later
NV3550
> > > used
> > > > in
> > > > > > the
> > > > > > > > > TJs. Check with your local dealer. Alternatively, you can
use
> > > > Redline
> > > > > > MTL.
> > > > > > > > > I've used it in my '94 YJ for years and swear by it.
> > > > > > > > >
> > > > > > > > >
> > > >
> > > >
> > >
> > >
original transmission fluid in my YJ. Coincidence or not, shortly
thereafter the second gear synchro went to hell. By the time I figured out
what had happened the original oil had been picked up by the curbside
recycling people. I got the transmission back to a semblance of normality
by putting Mobil 1 synthetic (75W90? without the limited slip modifier) in
it, but I still have to hit second at just the right rpm, or double clutch
it, to prevent grinding when shifting into that gear.
The original poster should drain his transmission fluid into a clean
container, strain it through a chamois, and pour it back in. ;o) Manual
transmissions "never" get hot enough to burn oil, and therefore the only two
likely sources of contamination are water and metal shavings. The chamois
will take care of the shavings. If the fluid is not cloudy or "milky" then
it doesn't have water in it and he is home free. I suppose you could also
use a time machine and go back far enough to buy some real GL3.
Earle
"Mike Romain" <romainm@sympatico.ca> wrote in message
news:410A80AC.47DA2446@sympatico.ca...
> You are still confusing as ----. ;-)
>
> Now you say it's 'ok' to use redline GL4, but don't do it because it's
> supposed to be GL3 which redline doesn't make, but use redline because
> it is better.
>
> Oh and 'don't use 90 weight because it won't shift, but meanwhile 'you'
> use MTL which 'is' 90 weight which is 'great stuff'.
>
> So just what the heck is it?
>
> 'I' know to use the GL4 'gear oil' for transmissions and to make sure
> it doesn't have the limited slip additive for differentials.
>
> 'I' could only find the GL4 diff fluid once when changing oil so used
> it. My shifter stopped working shortly after.
>
> 'I' then went and found tranny gear oil which only came in a semi
> synthetic at my local parts store, all the 'regular' gear oil had the
> limited slip or friction modifiers in, and now I have a sweet smooth
> shift.
>
> Mike
>
> Jerry McG wrote:
> >
> > Thanks, Jerry. If he's in a cold climate he may want to consider the
70w-80
> > fort improved cold shifting. I put the original fill of Red Line MTL in
my
> > '94 YJs AX15 at 30k miles. I changed it last year as part of the 60k
> > mainenance and noted the drain plug magnet didn't have a single flake of
> > metal on it. Great stuff!
> >
> > The owners manuals for the YJs and XJs through at least '96 also called
for
> > a 75w-90 GL5. I'm not sure when DC caught on and started using the GL3,
but
> > before that MTL was about the only thing available that would stop the
> > synchros.
> >
> > The 75w-90 GL3 sold by DC is quite pricey but works well. I put it in my
'96
> > YJs AX15 three years ago and it immediately eliminated hard cold
shifitng.
> > When I looked this a few months ago the dealer came up with two
different
> > gear oil part 3's, one recommended for the AX15, another for the NV3550.
> > They claim to have used the latter with success in the AX15, but if one
is
> > ordering this stuff might as well get the correct number.
> >
> > "Jerry Bransford" <jerrypb@***.net> wrote in message
> > news:VjjOc.4251$Xn.52@fed1read05...
> > > It calls for a 75W-90 GL-3, and there were some years when the shop
> > manuals
> > > incorrectly called for a 75W-90 GL-5. Redline's MT-90 is a 75W-90
GL-4,
> > MTL
> > > is 70W-80 GL-4. If you go with Redline, MT-90 is the correct
viscosity.
> > >
> > > Jerry
> > > --
> > > Jerry Bransford
> > > PP-ASEL N6TAY
> > > See the Geezer Jeep at
> > > http://members.***.net/jerrypb/
> > > "Jerry McG" <gmcgeorge.remove@frontier.net> wrote in message
> > > news:cecdh601c6u@enews4.newsguy.com...
> > > > Mike,
> > > >
> > > > The original manuals called for a 75w-90 GL5 oil and were corrected
by
> > > tech
> > > > service bulletin years ago. Any 80w-90, even if a lower sulphur GL4,
is
> > > far
> > > > too heavy a lubricant for an AX15 or NV3550. I believe Redline MTL
is a
> > > > 70w-80 GL4.
> > > >
> > > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > news:41096C62.7A63CE5E@sympatico.ca...
> > > > > Sorry if I got mouthy.
> > > > >
> > > > > It is still 80W90 gear oil he needs. You are mixing up terms.
> > > > >
> > > > > The GL rating has nothing to do with the weight of 80W90.
> > > > >
> > > > > Mike
> > > > >
> > > > > Jerry McG wrote:
> > > > > >
> > > > > > Mike,
> > > > > >
> > > > > > I find your description of my assitance to this guy offensive
and
> > > > > > uncharacteristic of you. What I stated is fact. The AX15 can not
> > > > tolerate
> > > > > > 80w-90 GL5 gear oil. DC recommends a special GL3 (no sulphur)
oil
> > > > available
> > > > > > from Jeep dealers. They also make a special GL3 oil for the
NV3550,
> > > > which
> > > > > > has the same issue re: GL5 oils.
> > > > > >
> > > > > > If he uses any form of GL5 gear oil he will experience difficult
to
> > > > > > impossible shifting (esp. in extreme cold) and substantial gear
> > clash.
> > > > Sorry
> > > > > > if my reply offended you, it's just the facts.
> > > > > >
> > > > > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > > > news:41092D32.D9F68E4B@sympatico.ca...
> > > > > > > He just fed you a pile of BS. Not much to thank him for.
> > > > > > >
> > > > > > > Your transfer case takes ATF and your tranny takes 80W90 GL4
'gear
> > > > oil'.
> > > > > > >
> > > > > > > Mike
> > > > > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > > > > 88 Cherokee 235 BFG AT's
> > > > > > >
> > > > > > > Brian Hubley wrote:
> > > > > > > >
> > > > > > > > Thanx Jerry
> > > > > > > >
> > > > > > > > "Jerry McG" <gmcgeorge.remove@frontier.net> wrote in message
> > > > > > > > news:ce9ko42im7@enews1.newsguy.com...
> > > > > > > > >
> > > > > > > > > "Brian Hubley" <brianhubley422@earthlink.net> wrote in
message
> > > > > > > > >
news:7hONc.16881$iK.10045@newsread2.news.atl.earth link.net...
> > > > > > > > > > I have a 91 YJ 4.0L manual with alot of miles I bought
not
> > to
> > > > long
> > > > > > ago.
> > > > > > > > I
> > > > > > > > > > would like to change the fluid in the trans and transfer
> > case.
> > > I
> > > > was
> > > > > > > > told
> > > > > > > > > 80
> > > > > > > > > > 90 for the trans, and I haven't checked on the transfer
case
> > > > yet.
> > > > > > > > Someone
> > > > > > > > > > else told me it might need automatic fluid or a
different
> > type
> > > > of
> > > > > > fluid
> > > > > > > > > for
> > > > > > > > > > the trans so I haven't done anything yet. I don't have
the
> > > > manual of
> > > > > > > > > course.
> > > > > > > > > > What should I do? Any web resource's out there?
> > > > > > > > > >
> > > > > > > > > > Would Daimler Chrysler know? I have been told they only
go
> > > back
> > > > so
> > > > > > many
> > > > > > > > > > years?
> > > > > > > > > >
> > > > > > > > > > Any suggestions would be a great help to me.
> > > > > > > > > >
> > > > > > > > > > -Brian
> > > > > > > > >
> > > > > > > > > DO NOT put 80w-90 in your transmission. It requires a GL3
or
> > GL4
> > > > (low
> > > > > > or
> > > > > > > > no
> > > > > > > > > sulphur) gear oil, other wise the synchros will not be
able to
> > > > > > function
> > > > > > > > > properly and you'll get serious cold gear clash when
shifting.
> > > DC
> > > > has
> > > > > > a
> > > > > > > > > special gear oil for AX15s, plus another for the later
NV3550
> > > used
> > > > in
> > > > > > the
> > > > > > > > > TJs. Check with your local dealer. Alternatively, you can
use
> > > > Redline
> > > > > > MTL.
> > > > > > > > > I've used it in my '94 YJ for years and swear by it.
> > > > > > > > >
> > > > > > > > >
> > > >
> > > >
> > >
> > >
07-31-2004, 12:29 AM
#55
Guest
Posts: n/a
Re: Correct Trans and diff fluid for a YJ
Heh, one of the few things I regret doing in this life is changing the
original transmission fluid in my YJ. Coincidence or not, shortly
thereafter the second gear synchro went to hell. By the time I figured out
what had happened the original oil had been picked up by the curbside
recycling people. I got the transmission back to a semblance of normality
by putting Mobil 1 synthetic (75W90? without the limited slip modifier) in
it, but I still have to hit second at just the right rpm, or double clutch
it, to prevent grinding when shifting into that gear.
The original poster should drain his transmission fluid into a clean
container, strain it through a chamois, and pour it back in. ;o) Manual
transmissions "never" get hot enough to burn oil, and therefore the only two
likely sources of contamination are water and metal shavings. The chamois
will take care of the shavings. If the fluid is not cloudy or "milky" then
it doesn't have water in it and he is home free. I suppose you could also
use a time machine and go back far enough to buy some real GL3.
Earle
"Mike Romain" <romainm@sympatico.ca> wrote in message
news:410A80AC.47DA2446@sympatico.ca...
> You are still confusing as ----. ;-)
>
> Now you say it's 'ok' to use redline GL4, but don't do it because it's
> supposed to be GL3 which redline doesn't make, but use redline because
> it is better.
>
> Oh and 'don't use 90 weight because it won't shift, but meanwhile 'you'
> use MTL which 'is' 90 weight which is 'great stuff'.
>
> So just what the heck is it?
>
> 'I' know to use the GL4 'gear oil' for transmissions and to make sure
> it doesn't have the limited slip additive for differentials.
>
> 'I' could only find the GL4 diff fluid once when changing oil so used
> it. My shifter stopped working shortly after.
>
> 'I' then went and found tranny gear oil which only came in a semi
> synthetic at my local parts store, all the 'regular' gear oil had the
> limited slip or friction modifiers in, and now I have a sweet smooth
> shift.
>
> Mike
>
> Jerry McG wrote:
> >
> > Thanks, Jerry. If he's in a cold climate he may want to consider the
70w-80
> > fort improved cold shifting. I put the original fill of Red Line MTL in
my
> > '94 YJs AX15 at 30k miles. I changed it last year as part of the 60k
> > mainenance and noted the drain plug magnet didn't have a single flake of
> > metal on it. Great stuff!
> >
> > The owners manuals for the YJs and XJs through at least '96 also called
for
> > a 75w-90 GL5. I'm not sure when DC caught on and started using the GL3,
but
> > before that MTL was about the only thing available that would stop the
> > synchros.
> >
> > The 75w-90 GL3 sold by DC is quite pricey but works well. I put it in my
'96
> > YJs AX15 three years ago and it immediately eliminated hard cold
shifitng.
> > When I looked this a few months ago the dealer came up with two
different
> > gear oil part 3's, one recommended for the AX15, another for the NV3550.
> > They claim to have used the latter with success in the AX15, but if one
is
> > ordering this stuff might as well get the correct number.
> >
> > "Jerry Bransford" <jerrypb@***.net> wrote in message
> > news:VjjOc.4251$Xn.52@fed1read05...
> > > It calls for a 75W-90 GL-3, and there were some years when the shop
> > manuals
> > > incorrectly called for a 75W-90 GL-5. Redline's MT-90 is a 75W-90
GL-4,
> > MTL
> > > is 70W-80 GL-4. If you go with Redline, MT-90 is the correct
viscosity.
> > >
> > > Jerry
> > > --
> > > Jerry Bransford
> > > PP-ASEL N6TAY
> > > See the Geezer Jeep at
> > > http://members.***.net/jerrypb/
> > > "Jerry McG" <gmcgeorge.remove@frontier.net> wrote in message
> > > news:cecdh601c6u@enews4.newsguy.com...
> > > > Mike,
> > > >
> > > > The original manuals called for a 75w-90 GL5 oil and were corrected
by
> > > tech
> > > > service bulletin years ago. Any 80w-90, even if a lower sulphur GL4,
is
> > > far
> > > > too heavy a lubricant for an AX15 or NV3550. I believe Redline MTL
is a
> > > > 70w-80 GL4.
> > > >
> > > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > news:41096C62.7A63CE5E@sympatico.ca...
> > > > > Sorry if I got mouthy.
> > > > >
> > > > > It is still 80W90 gear oil he needs. You are mixing up terms.
> > > > >
> > > > > The GL rating has nothing to do with the weight of 80W90.
> > > > >
> > > > > Mike
> > > > >
> > > > > Jerry McG wrote:
> > > > > >
> > > > > > Mike,
> > > > > >
> > > > > > I find your description of my assitance to this guy offensive
and
> > > > > > uncharacteristic of you. What I stated is fact. The AX15 can not
> > > > tolerate
> > > > > > 80w-90 GL5 gear oil. DC recommends a special GL3 (no sulphur)
oil
> > > > available
> > > > > > from Jeep dealers. They also make a special GL3 oil for the
NV3550,
> > > > which
> > > > > > has the same issue re: GL5 oils.
> > > > > >
> > > > > > If he uses any form of GL5 gear oil he will experience difficult
to
> > > > > > impossible shifting (esp. in extreme cold) and substantial gear
> > clash.
> > > > Sorry
> > > > > > if my reply offended you, it's just the facts.
> > > > > >
> > > > > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > > > news:41092D32.D9F68E4B@sympatico.ca...
> > > > > > > He just fed you a pile of BS. Not much to thank him for.
> > > > > > >
> > > > > > > Your transfer case takes ATF and your tranny takes 80W90 GL4
'gear
> > > > oil'.
> > > > > > >
> > > > > > > Mike
> > > > > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > > > > 88 Cherokee 235 BFG AT's
> > > > > > >
> > > > > > > Brian Hubley wrote:
> > > > > > > >
> > > > > > > > Thanx Jerry
> > > > > > > >
> > > > > > > > "Jerry McG" <gmcgeorge.remove@frontier.net> wrote in message
> > > > > > > > news:ce9ko42im7@enews1.newsguy.com...
> > > > > > > > >
> > > > > > > > > "Brian Hubley" <brianhubley422@earthlink.net> wrote in
message
> > > > > > > > >
news:7hONc.16881$iK.10045@newsread2.news.atl.earth link.net...
> > > > > > > > > > I have a 91 YJ 4.0L manual with alot of miles I bought
not
> > to
> > > > long
> > > > > > ago.
> > > > > > > > I
> > > > > > > > > > would like to change the fluid in the trans and transfer
> > case.
> > > I
> > > > was
> > > > > > > > told
> > > > > > > > > 80
> > > > > > > > > > 90 for the trans, and I haven't checked on the transfer
case
> > > > yet.
> > > > > > > > Someone
> > > > > > > > > > else told me it might need automatic fluid or a
different
> > type
> > > > of
> > > > > > fluid
> > > > > > > > > for
> > > > > > > > > > the trans so I haven't done anything yet. I don't have
the
> > > > manual of
> > > > > > > > > course.
> > > > > > > > > > What should I do? Any web resource's out there?
> > > > > > > > > >
> > > > > > > > > > Would Daimler Chrysler know? I have been told they only
go
> > > back
> > > > so
> > > > > > many
> > > > > > > > > > years?
> > > > > > > > > >
> > > > > > > > > > Any suggestions would be a great help to me.
> > > > > > > > > >
> > > > > > > > > > -Brian
> > > > > > > > >
> > > > > > > > > DO NOT put 80w-90 in your transmission. It requires a GL3
or
> > GL4
> > > > (low
> > > > > > or
> > > > > > > > no
> > > > > > > > > sulphur) gear oil, other wise the synchros will not be
able to
> > > > > > function
> > > > > > > > > properly and you'll get serious cold gear clash when
shifting.
> > > DC
> > > > has
> > > > > > a
> > > > > > > > > special gear oil for AX15s, plus another for the later
NV3550
> > > used
> > > > in
> > > > > > the
> > > > > > > > > TJs. Check with your local dealer. Alternatively, you can
use
> > > > Redline
> > > > > > MTL.
> > > > > > > > > I've used it in my '94 YJ for years and swear by it.
> > > > > > > > >
> > > > > > > > >
> > > >
> > > >
> > >
> > >
original transmission fluid in my YJ. Coincidence or not, shortly
thereafter the second gear synchro went to hell. By the time I figured out
what had happened the original oil had been picked up by the curbside
recycling people. I got the transmission back to a semblance of normality
by putting Mobil 1 synthetic (75W90? without the limited slip modifier) in
it, but I still have to hit second at just the right rpm, or double clutch
it, to prevent grinding when shifting into that gear.
The original poster should drain his transmission fluid into a clean
container, strain it through a chamois, and pour it back in. ;o) Manual
transmissions "never" get hot enough to burn oil, and therefore the only two
likely sources of contamination are water and metal shavings. The chamois
will take care of the shavings. If the fluid is not cloudy or "milky" then
it doesn't have water in it and he is home free. I suppose you could also
use a time machine and go back far enough to buy some real GL3.
Earle
"Mike Romain" <romainm@sympatico.ca> wrote in message
news:410A80AC.47DA2446@sympatico.ca...
> You are still confusing as ----. ;-)
>
> Now you say it's 'ok' to use redline GL4, but don't do it because it's
> supposed to be GL3 which redline doesn't make, but use redline because
> it is better.
>
> Oh and 'don't use 90 weight because it won't shift, but meanwhile 'you'
> use MTL which 'is' 90 weight which is 'great stuff'.
>
> So just what the heck is it?
>
> 'I' know to use the GL4 'gear oil' for transmissions and to make sure
> it doesn't have the limited slip additive for differentials.
>
> 'I' could only find the GL4 diff fluid once when changing oil so used
> it. My shifter stopped working shortly after.
>
> 'I' then went and found tranny gear oil which only came in a semi
> synthetic at my local parts store, all the 'regular' gear oil had the
> limited slip or friction modifiers in, and now I have a sweet smooth
> shift.
>
> Mike
>
> Jerry McG wrote:
> >
> > Thanks, Jerry. If he's in a cold climate he may want to consider the
70w-80
> > fort improved cold shifting. I put the original fill of Red Line MTL in
my
> > '94 YJs AX15 at 30k miles. I changed it last year as part of the 60k
> > mainenance and noted the drain plug magnet didn't have a single flake of
> > metal on it. Great stuff!
> >
> > The owners manuals for the YJs and XJs through at least '96 also called
for
> > a 75w-90 GL5. I'm not sure when DC caught on and started using the GL3,
but
> > before that MTL was about the only thing available that would stop the
> > synchros.
> >
> > The 75w-90 GL3 sold by DC is quite pricey but works well. I put it in my
'96
> > YJs AX15 three years ago and it immediately eliminated hard cold
shifitng.
> > When I looked this a few months ago the dealer came up with two
different
> > gear oil part 3's, one recommended for the AX15, another for the NV3550.
> > They claim to have used the latter with success in the AX15, but if one
is
> > ordering this stuff might as well get the correct number.
> >
> > "Jerry Bransford" <jerrypb@***.net> wrote in message
> > news:VjjOc.4251$Xn.52@fed1read05...
> > > It calls for a 75W-90 GL-3, and there were some years when the shop
> > manuals
> > > incorrectly called for a 75W-90 GL-5. Redline's MT-90 is a 75W-90
GL-4,
> > MTL
> > > is 70W-80 GL-4. If you go with Redline, MT-90 is the correct
viscosity.
> > >
> > > Jerry
> > > --
> > > Jerry Bransford
> > > PP-ASEL N6TAY
> > > See the Geezer Jeep at
> > > http://members.***.net/jerrypb/
> > > "Jerry McG" <gmcgeorge.remove@frontier.net> wrote in message
> > > news:cecdh601c6u@enews4.newsguy.com...
> > > > Mike,
> > > >
> > > > The original manuals called for a 75w-90 GL5 oil and were corrected
by
> > > tech
> > > > service bulletin years ago. Any 80w-90, even if a lower sulphur GL4,
is
> > > far
> > > > too heavy a lubricant for an AX15 or NV3550. I believe Redline MTL
is a
> > > > 70w-80 GL4.
> > > >
> > > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > news:41096C62.7A63CE5E@sympatico.ca...
> > > > > Sorry if I got mouthy.
> > > > >
> > > > > It is still 80W90 gear oil he needs. You are mixing up terms.
> > > > >
> > > > > The GL rating has nothing to do with the weight of 80W90.
> > > > >
> > > > > Mike
> > > > >
> > > > > Jerry McG wrote:
> > > > > >
> > > > > > Mike,
> > > > > >
> > > > > > I find your description of my assitance to this guy offensive
and
> > > > > > uncharacteristic of you. What I stated is fact. The AX15 can not
> > > > tolerate
> > > > > > 80w-90 GL5 gear oil. DC recommends a special GL3 (no sulphur)
oil
> > > > available
> > > > > > from Jeep dealers. They also make a special GL3 oil for the
NV3550,
> > > > which
> > > > > > has the same issue re: GL5 oils.
> > > > > >
> > > > > > If he uses any form of GL5 gear oil he will experience difficult
to
> > > > > > impossible shifting (esp. in extreme cold) and substantial gear
> > clash.
> > > > Sorry
> > > > > > if my reply offended you, it's just the facts.
> > > > > >
> > > > > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > > > news:41092D32.D9F68E4B@sympatico.ca...
> > > > > > > He just fed you a pile of BS. Not much to thank him for.
> > > > > > >
> > > > > > > Your transfer case takes ATF and your tranny takes 80W90 GL4
'gear
> > > > oil'.
> > > > > > >
> > > > > > > Mike
> > > > > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > > > > 88 Cherokee 235 BFG AT's
> > > > > > >
> > > > > > > Brian Hubley wrote:
> > > > > > > >
> > > > > > > > Thanx Jerry
> > > > > > > >
> > > > > > > > "Jerry McG" <gmcgeorge.remove@frontier.net> wrote in message
> > > > > > > > news:ce9ko42im7@enews1.newsguy.com...
> > > > > > > > >
> > > > > > > > > "Brian Hubley" <brianhubley422@earthlink.net> wrote in
message
> > > > > > > > >
news:7hONc.16881$iK.10045@newsread2.news.atl.earth link.net...
> > > > > > > > > > I have a 91 YJ 4.0L manual with alot of miles I bought
not
> > to
> > > > long
> > > > > > ago.
> > > > > > > > I
> > > > > > > > > > would like to change the fluid in the trans and transfer
> > case.
> > > I
> > > > was
> > > > > > > > told
> > > > > > > > > 80
> > > > > > > > > > 90 for the trans, and I haven't checked on the transfer
case
> > > > yet.
> > > > > > > > Someone
> > > > > > > > > > else told me it might need automatic fluid or a
different
> > type
> > > > of
> > > > > > fluid
> > > > > > > > > for
> > > > > > > > > > the trans so I haven't done anything yet. I don't have
the
> > > > manual of
> > > > > > > > > course.
> > > > > > > > > > What should I do? Any web resource's out there?
> > > > > > > > > >
> > > > > > > > > > Would Daimler Chrysler know? I have been told they only
go
> > > back
> > > > so
> > > > > > many
> > > > > > > > > > years?
> > > > > > > > > >
> > > > > > > > > > Any suggestions would be a great help to me.
> > > > > > > > > >
> > > > > > > > > > -Brian
> > > > > > > > >
> > > > > > > > > DO NOT put 80w-90 in your transmission. It requires a GL3
or
> > GL4
> > > > (low
> > > > > > or
> > > > > > > > no
> > > > > > > > > sulphur) gear oil, other wise the synchros will not be
able to
> > > > > > function
> > > > > > > > > properly and you'll get serious cold gear clash when
shifting.
> > > DC
> > > > has
> > > > > > a
> > > > > > > > > special gear oil for AX15s, plus another for the later
NV3550
> > > used
> > > > in
> > > > > > the
> > > > > > > > > TJs. Check with your local dealer. Alternatively, you can
use
> > > > Redline
> > > > > > MTL.
> > > > > > > > > I've used it in my '94 YJ for years and swear by it.
> > > > > > > > >
> > > > > > > > >
> > > >
> > > >
> > >
> > >
07-31-2004, 12:29 AM
#56
Guest
Posts: n/a
Re: Correct Trans and diff fluid for a YJ
Heh, one of the few things I regret doing in this life is changing the
original transmission fluid in my YJ. Coincidence or not, shortly
thereafter the second gear synchro went to hell. By the time I figured out
what had happened the original oil had been picked up by the curbside
recycling people. I got the transmission back to a semblance of normality
by putting Mobil 1 synthetic (75W90? without the limited slip modifier) in
it, but I still have to hit second at just the right rpm, or double clutch
it, to prevent grinding when shifting into that gear.
The original poster should drain his transmission fluid into a clean
container, strain it through a chamois, and pour it back in. ;o) Manual
transmissions "never" get hot enough to burn oil, and therefore the only two
likely sources of contamination are water and metal shavings. The chamois
will take care of the shavings. If the fluid is not cloudy or "milky" then
it doesn't have water in it and he is home free. I suppose you could also
use a time machine and go back far enough to buy some real GL3.
Earle
"Mike Romain" <romainm@sympatico.ca> wrote in message
news:410A80AC.47DA2446@sympatico.ca...
> You are still confusing as ----. ;-)
>
> Now you say it's 'ok' to use redline GL4, but don't do it because it's
> supposed to be GL3 which redline doesn't make, but use redline because
> it is better.
>
> Oh and 'don't use 90 weight because it won't shift, but meanwhile 'you'
> use MTL which 'is' 90 weight which is 'great stuff'.
>
> So just what the heck is it?
>
> 'I' know to use the GL4 'gear oil' for transmissions and to make sure
> it doesn't have the limited slip additive for differentials.
>
> 'I' could only find the GL4 diff fluid once when changing oil so used
> it. My shifter stopped working shortly after.
>
> 'I' then went and found tranny gear oil which only came in a semi
> synthetic at my local parts store, all the 'regular' gear oil had the
> limited slip or friction modifiers in, and now I have a sweet smooth
> shift.
>
> Mike
>
> Jerry McG wrote:
> >
> > Thanks, Jerry. If he's in a cold climate he may want to consider the
70w-80
> > fort improved cold shifting. I put the original fill of Red Line MTL in
my
> > '94 YJs AX15 at 30k miles. I changed it last year as part of the 60k
> > mainenance and noted the drain plug magnet didn't have a single flake of
> > metal on it. Great stuff!
> >
> > The owners manuals for the YJs and XJs through at least '96 also called
for
> > a 75w-90 GL5. I'm not sure when DC caught on and started using the GL3,
but
> > before that MTL was about the only thing available that would stop the
> > synchros.
> >
> > The 75w-90 GL3 sold by DC is quite pricey but works well. I put it in my
'96
> > YJs AX15 three years ago and it immediately eliminated hard cold
shifitng.
> > When I looked this a few months ago the dealer came up with two
different
> > gear oil part 3's, one recommended for the AX15, another for the NV3550.
> > They claim to have used the latter with success in the AX15, but if one
is
> > ordering this stuff might as well get the correct number.
> >
> > "Jerry Bransford" <jerrypb@***.net> wrote in message
> > news:VjjOc.4251$Xn.52@fed1read05...
> > > It calls for a 75W-90 GL-3, and there were some years when the shop
> > manuals
> > > incorrectly called for a 75W-90 GL-5. Redline's MT-90 is a 75W-90
GL-4,
> > MTL
> > > is 70W-80 GL-4. If you go with Redline, MT-90 is the correct
viscosity.
> > >
> > > Jerry
> > > --
> > > Jerry Bransford
> > > PP-ASEL N6TAY
> > > See the Geezer Jeep at
> > > http://members.***.net/jerrypb/
> > > "Jerry McG" <gmcgeorge.remove@frontier.net> wrote in message
> > > news:cecdh601c6u@enews4.newsguy.com...
> > > > Mike,
> > > >
> > > > The original manuals called for a 75w-90 GL5 oil and were corrected
by
> > > tech
> > > > service bulletin years ago. Any 80w-90, even if a lower sulphur GL4,
is
> > > far
> > > > too heavy a lubricant for an AX15 or NV3550. I believe Redline MTL
is a
> > > > 70w-80 GL4.
> > > >
> > > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > news:41096C62.7A63CE5E@sympatico.ca...
> > > > > Sorry if I got mouthy.
> > > > >
> > > > > It is still 80W90 gear oil he needs. You are mixing up terms.
> > > > >
> > > > > The GL rating has nothing to do with the weight of 80W90.
> > > > >
> > > > > Mike
> > > > >
> > > > > Jerry McG wrote:
> > > > > >
> > > > > > Mike,
> > > > > >
> > > > > > I find your description of my assitance to this guy offensive
and
> > > > > > uncharacteristic of you. What I stated is fact. The AX15 can not
> > > > tolerate
> > > > > > 80w-90 GL5 gear oil. DC recommends a special GL3 (no sulphur)
oil
> > > > available
> > > > > > from Jeep dealers. They also make a special GL3 oil for the
NV3550,
> > > > which
> > > > > > has the same issue re: GL5 oils.
> > > > > >
> > > > > > If he uses any form of GL5 gear oil he will experience difficult
to
> > > > > > impossible shifting (esp. in extreme cold) and substantial gear
> > clash.
> > > > Sorry
> > > > > > if my reply offended you, it's just the facts.
> > > > > >
> > > > > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > > > news:41092D32.D9F68E4B@sympatico.ca...
> > > > > > > He just fed you a pile of BS. Not much to thank him for.
> > > > > > >
> > > > > > > Your transfer case takes ATF and your tranny takes 80W90 GL4
'gear
> > > > oil'.
> > > > > > >
> > > > > > > Mike
> > > > > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > > > > 88 Cherokee 235 BFG AT's
> > > > > > >
> > > > > > > Brian Hubley wrote:
> > > > > > > >
> > > > > > > > Thanx Jerry
> > > > > > > >
> > > > > > > > "Jerry McG" <gmcgeorge.remove@frontier.net> wrote in message
> > > > > > > > news:ce9ko42im7@enews1.newsguy.com...
> > > > > > > > >
> > > > > > > > > "Brian Hubley" <brianhubley422@earthlink.net> wrote in
message
> > > > > > > > >
news:7hONc.16881$iK.10045@newsread2.news.atl.earth link.net...
> > > > > > > > > > I have a 91 YJ 4.0L manual with alot of miles I bought
not
> > to
> > > > long
> > > > > > ago.
> > > > > > > > I
> > > > > > > > > > would like to change the fluid in the trans and transfer
> > case.
> > > I
> > > > was
> > > > > > > > told
> > > > > > > > > 80
> > > > > > > > > > 90 for the trans, and I haven't checked on the transfer
case
> > > > yet.
> > > > > > > > Someone
> > > > > > > > > > else told me it might need automatic fluid or a
different
> > type
> > > > of
> > > > > > fluid
> > > > > > > > > for
> > > > > > > > > > the trans so I haven't done anything yet. I don't have
the
> > > > manual of
> > > > > > > > > course.
> > > > > > > > > > What should I do? Any web resource's out there?
> > > > > > > > > >
> > > > > > > > > > Would Daimler Chrysler know? I have been told they only
go
> > > back
> > > > so
> > > > > > many
> > > > > > > > > > years?
> > > > > > > > > >
> > > > > > > > > > Any suggestions would be a great help to me.
> > > > > > > > > >
> > > > > > > > > > -Brian
> > > > > > > > >
> > > > > > > > > DO NOT put 80w-90 in your transmission. It requires a GL3
or
> > GL4
> > > > (low
> > > > > > or
> > > > > > > > no
> > > > > > > > > sulphur) gear oil, other wise the synchros will not be
able to
> > > > > > function
> > > > > > > > > properly and you'll get serious cold gear clash when
shifting.
> > > DC
> > > > has
> > > > > > a
> > > > > > > > > special gear oil for AX15s, plus another for the later
NV3550
> > > used
> > > > in
> > > > > > the
> > > > > > > > > TJs. Check with your local dealer. Alternatively, you can
use
> > > > Redline
> > > > > > MTL.
> > > > > > > > > I've used it in my '94 YJ for years and swear by it.
> > > > > > > > >
> > > > > > > > >
> > > >
> > > >
> > >
> > >
original transmission fluid in my YJ. Coincidence or not, shortly
thereafter the second gear synchro went to hell. By the time I figured out
what had happened the original oil had been picked up by the curbside
recycling people. I got the transmission back to a semblance of normality
by putting Mobil 1 synthetic (75W90? without the limited slip modifier) in
it, but I still have to hit second at just the right rpm, or double clutch
it, to prevent grinding when shifting into that gear.
The original poster should drain his transmission fluid into a clean
container, strain it through a chamois, and pour it back in. ;o) Manual
transmissions "never" get hot enough to burn oil, and therefore the only two
likely sources of contamination are water and metal shavings. The chamois
will take care of the shavings. If the fluid is not cloudy or "milky" then
it doesn't have water in it and he is home free. I suppose you could also
use a time machine and go back far enough to buy some real GL3.
Earle
"Mike Romain" <romainm@sympatico.ca> wrote in message
news:410A80AC.47DA2446@sympatico.ca...
> You are still confusing as ----. ;-)
>
> Now you say it's 'ok' to use redline GL4, but don't do it because it's
> supposed to be GL3 which redline doesn't make, but use redline because
> it is better.
>
> Oh and 'don't use 90 weight because it won't shift, but meanwhile 'you'
> use MTL which 'is' 90 weight which is 'great stuff'.
>
> So just what the heck is it?
>
> 'I' know to use the GL4 'gear oil' for transmissions and to make sure
> it doesn't have the limited slip additive for differentials.
>
> 'I' could only find the GL4 diff fluid once when changing oil so used
> it. My shifter stopped working shortly after.
>
> 'I' then went and found tranny gear oil which only came in a semi
> synthetic at my local parts store, all the 'regular' gear oil had the
> limited slip or friction modifiers in, and now I have a sweet smooth
> shift.
>
> Mike
>
> Jerry McG wrote:
> >
> > Thanks, Jerry. If he's in a cold climate he may want to consider the
70w-80
> > fort improved cold shifting. I put the original fill of Red Line MTL in
my
> > '94 YJs AX15 at 30k miles. I changed it last year as part of the 60k
> > mainenance and noted the drain plug magnet didn't have a single flake of
> > metal on it. Great stuff!
> >
> > The owners manuals for the YJs and XJs through at least '96 also called
for
> > a 75w-90 GL5. I'm not sure when DC caught on and started using the GL3,
but
> > before that MTL was about the only thing available that would stop the
> > synchros.
> >
> > The 75w-90 GL3 sold by DC is quite pricey but works well. I put it in my
'96
> > YJs AX15 three years ago and it immediately eliminated hard cold
shifitng.
> > When I looked this a few months ago the dealer came up with two
different
> > gear oil part 3's, one recommended for the AX15, another for the NV3550.
> > They claim to have used the latter with success in the AX15, but if one
is
> > ordering this stuff might as well get the correct number.
> >
> > "Jerry Bransford" <jerrypb@***.net> wrote in message
> > news:VjjOc.4251$Xn.52@fed1read05...
> > > It calls for a 75W-90 GL-3, and there were some years when the shop
> > manuals
> > > incorrectly called for a 75W-90 GL-5. Redline's MT-90 is a 75W-90
GL-4,
> > MTL
> > > is 70W-80 GL-4. If you go with Redline, MT-90 is the correct
viscosity.
> > >
> > > Jerry
> > > --
> > > Jerry Bransford
> > > PP-ASEL N6TAY
> > > See the Geezer Jeep at
> > > http://members.***.net/jerrypb/
> > > "Jerry McG" <gmcgeorge.remove@frontier.net> wrote in message
> > > news:cecdh601c6u@enews4.newsguy.com...
> > > > Mike,
> > > >
> > > > The original manuals called for a 75w-90 GL5 oil and were corrected
by
> > > tech
> > > > service bulletin years ago. Any 80w-90, even if a lower sulphur GL4,
is
> > > far
> > > > too heavy a lubricant for an AX15 or NV3550. I believe Redline MTL
is a
> > > > 70w-80 GL4.
> > > >
> > > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > news:41096C62.7A63CE5E@sympatico.ca...
> > > > > Sorry if I got mouthy.
> > > > >
> > > > > It is still 80W90 gear oil he needs. You are mixing up terms.
> > > > >
> > > > > The GL rating has nothing to do with the weight of 80W90.
> > > > >
> > > > > Mike
> > > > >
> > > > > Jerry McG wrote:
> > > > > >
> > > > > > Mike,
> > > > > >
> > > > > > I find your description of my assitance to this guy offensive
and
> > > > > > uncharacteristic of you. What I stated is fact. The AX15 can not
> > > > tolerate
> > > > > > 80w-90 GL5 gear oil. DC recommends a special GL3 (no sulphur)
oil
> > > > available
> > > > > > from Jeep dealers. They also make a special GL3 oil for the
NV3550,
> > > > which
> > > > > > has the same issue re: GL5 oils.
> > > > > >
> > > > > > If he uses any form of GL5 gear oil he will experience difficult
to
> > > > > > impossible shifting (esp. in extreme cold) and substantial gear
> > clash.
> > > > Sorry
> > > > > > if my reply offended you, it's just the facts.
> > > > > >
> > > > > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > > > news:41092D32.D9F68E4B@sympatico.ca...
> > > > > > > He just fed you a pile of BS. Not much to thank him for.
> > > > > > >
> > > > > > > Your transfer case takes ATF and your tranny takes 80W90 GL4
'gear
> > > > oil'.
> > > > > > >
> > > > > > > Mike
> > > > > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > > > > 88 Cherokee 235 BFG AT's
> > > > > > >
> > > > > > > Brian Hubley wrote:
> > > > > > > >
> > > > > > > > Thanx Jerry
> > > > > > > >
> > > > > > > > "Jerry McG" <gmcgeorge.remove@frontier.net> wrote in message
> > > > > > > > news:ce9ko42im7@enews1.newsguy.com...
> > > > > > > > >
> > > > > > > > > "Brian Hubley" <brianhubley422@earthlink.net> wrote in
message
> > > > > > > > >
news:7hONc.16881$iK.10045@newsread2.news.atl.earth link.net...
> > > > > > > > > > I have a 91 YJ 4.0L manual with alot of miles I bought
not
> > to
> > > > long
> > > > > > ago.
> > > > > > > > I
> > > > > > > > > > would like to change the fluid in the trans and transfer
> > case.
> > > I
> > > > was
> > > > > > > > told
> > > > > > > > > 80
> > > > > > > > > > 90 for the trans, and I haven't checked on the transfer
case
> > > > yet.
> > > > > > > > Someone
> > > > > > > > > > else told me it might need automatic fluid or a
different
> > type
> > > > of
> > > > > > fluid
> > > > > > > > > for
> > > > > > > > > > the trans so I haven't done anything yet. I don't have
the
> > > > manual of
> > > > > > > > > course.
> > > > > > > > > > What should I do? Any web resource's out there?
> > > > > > > > > >
> > > > > > > > > > Would Daimler Chrysler know? I have been told they only
go
> > > back
> > > > so
> > > > > > many
> > > > > > > > > > years?
> > > > > > > > > >
> > > > > > > > > > Any suggestions would be a great help to me.
> > > > > > > > > >
> > > > > > > > > > -Brian
> > > > > > > > >
> > > > > > > > > DO NOT put 80w-90 in your transmission. It requires a GL3
or
> > GL4
> > > > (low
> > > > > > or
> > > > > > > > no
> > > > > > > > > sulphur) gear oil, other wise the synchros will not be
able to
> > > > > > function
> > > > > > > > > properly and you'll get serious cold gear clash when
shifting.
> > > DC
> > > > has
> > > > > > a
> > > > > > > > > special gear oil for AX15s, plus another for the later
NV3550
> > > used
> > > > in
> > > > > > the
> > > > > > > > > TJs. Check with your local dealer. Alternatively, you can
use
> > > > Redline
> > > > > > MTL.
> > > > > > > > > I've used it in my '94 YJ for years and swear by it.
> > > > > > > > >
> > > > > > > > >
> > > >
> > > >
> > >
> > >
07-31-2004, 12:29 AM
#57
Guest
Posts: n/a
Re: Correct Trans and diff fluid for a YJ
Heh, one of the few things I regret doing in this life is changing the
original transmission fluid in my YJ. Coincidence or not, shortly
thereafter the second gear synchro went to hell. By the time I figured out
what had happened the original oil had been picked up by the curbside
recycling people. I got the transmission back to a semblance of normality
by putting Mobil 1 synthetic (75W90? without the limited slip modifier) in
it, but I still have to hit second at just the right rpm, or double clutch
it, to prevent grinding when shifting into that gear.
The original poster should drain his transmission fluid into a clean
container, strain it through a chamois, and pour it back in. ;o) Manual
transmissions "never" get hot enough to burn oil, and therefore the only two
likely sources of contamination are water and metal shavings. The chamois
will take care of the shavings. If the fluid is not cloudy or "milky" then
it doesn't have water in it and he is home free. I suppose you could also
use a time machine and go back far enough to buy some real GL3.
Earle
"Mike Romain" <romainm@sympatico.ca> wrote in message
news:410A80AC.47DA2446@sympatico.ca...
> You are still confusing as ----. ;-)
>
> Now you say it's 'ok' to use redline GL4, but don't do it because it's
> supposed to be GL3 which redline doesn't make, but use redline because
> it is better.
>
> Oh and 'don't use 90 weight because it won't shift, but meanwhile 'you'
> use MTL which 'is' 90 weight which is 'great stuff'.
>
> So just what the heck is it?
>
> 'I' know to use the GL4 'gear oil' for transmissions and to make sure
> it doesn't have the limited slip additive for differentials.
>
> 'I' could only find the GL4 diff fluid once when changing oil so used
> it. My shifter stopped working shortly after.
>
> 'I' then went and found tranny gear oil which only came in a semi
> synthetic at my local parts store, all the 'regular' gear oil had the
> limited slip or friction modifiers in, and now I have a sweet smooth
> shift.
>
> Mike
>
> Jerry McG wrote:
> >
> > Thanks, Jerry. If he's in a cold climate he may want to consider the
70w-80
> > fort improved cold shifting. I put the original fill of Red Line MTL in
my
> > '94 YJs AX15 at 30k miles. I changed it last year as part of the 60k
> > mainenance and noted the drain plug magnet didn't have a single flake of
> > metal on it. Great stuff!
> >
> > The owners manuals for the YJs and XJs through at least '96 also called
for
> > a 75w-90 GL5. I'm not sure when DC caught on and started using the GL3,
but
> > before that MTL was about the only thing available that would stop the
> > synchros.
> >
> > The 75w-90 GL3 sold by DC is quite pricey but works well. I put it in my
'96
> > YJs AX15 three years ago and it immediately eliminated hard cold
shifitng.
> > When I looked this a few months ago the dealer came up with two
different
> > gear oil part 3's, one recommended for the AX15, another for the NV3550.
> > They claim to have used the latter with success in the AX15, but if one
is
> > ordering this stuff might as well get the correct number.
> >
> > "Jerry Bransford" <jerrypb@***.net> wrote in message
> > news:VjjOc.4251$Xn.52@fed1read05...
> > > It calls for a 75W-90 GL-3, and there were some years when the shop
> > manuals
> > > incorrectly called for a 75W-90 GL-5. Redline's MT-90 is a 75W-90
GL-4,
> > MTL
> > > is 70W-80 GL-4. If you go with Redline, MT-90 is the correct
viscosity.
> > >
> > > Jerry
> > > --
> > > Jerry Bransford
> > > PP-ASEL N6TAY
> > > See the Geezer Jeep at
> > > http://members.***.net/jerrypb/
> > > "Jerry McG" <gmcgeorge.remove@frontier.net> wrote in message
> > > news:cecdh601c6u@enews4.newsguy.com...
> > > > Mike,
> > > >
> > > > The original manuals called for a 75w-90 GL5 oil and were corrected
by
> > > tech
> > > > service bulletin years ago. Any 80w-90, even if a lower sulphur GL4,
is
> > > far
> > > > too heavy a lubricant for an AX15 or NV3550. I believe Redline MTL
is a
> > > > 70w-80 GL4.
> > > >
> > > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > news:41096C62.7A63CE5E@sympatico.ca...
> > > > > Sorry if I got mouthy.
> > > > >
> > > > > It is still 80W90 gear oil he needs. You are mixing up terms.
> > > > >
> > > > > The GL rating has nothing to do with the weight of 80W90.
> > > > >
> > > > > Mike
> > > > >
> > > > > Jerry McG wrote:
> > > > > >
> > > > > > Mike,
> > > > > >
> > > > > > I find your description of my assitance to this guy offensive
and
> > > > > > uncharacteristic of you. What I stated is fact. The AX15 can not
> > > > tolerate
> > > > > > 80w-90 GL5 gear oil. DC recommends a special GL3 (no sulphur)
oil
> > > > available
> > > > > > from Jeep dealers. They also make a special GL3 oil for the
NV3550,
> > > > which
> > > > > > has the same issue re: GL5 oils.
> > > > > >
> > > > > > If he uses any form of GL5 gear oil he will experience difficult
to
> > > > > > impossible shifting (esp. in extreme cold) and substantial gear
> > clash.
> > > > Sorry
> > > > > > if my reply offended you, it's just the facts.
> > > > > >
> > > > > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > > > news:41092D32.D9F68E4B@sympatico.ca...
> > > > > > > He just fed you a pile of BS. Not much to thank him for.
> > > > > > >
> > > > > > > Your transfer case takes ATF and your tranny takes 80W90 GL4
'gear
> > > > oil'.
> > > > > > >
> > > > > > > Mike
> > > > > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > > > > 88 Cherokee 235 BFG AT's
> > > > > > >
> > > > > > > Brian Hubley wrote:
> > > > > > > >
> > > > > > > > Thanx Jerry
> > > > > > > >
> > > > > > > > "Jerry McG" <gmcgeorge.remove@frontier.net> wrote in message
> > > > > > > > news:ce9ko42im7@enews1.newsguy.com...
> > > > > > > > >
> > > > > > > > > "Brian Hubley" <brianhubley422@earthlink.net> wrote in
message
> > > > > > > > >
news:7hONc.16881$iK.10045@newsread2.news.atl.earth link.net...
> > > > > > > > > > I have a 91 YJ 4.0L manual with alot of miles I bought
not
> > to
> > > > long
> > > > > > ago.
> > > > > > > > I
> > > > > > > > > > would like to change the fluid in the trans and transfer
> > case.
> > > I
> > > > was
> > > > > > > > told
> > > > > > > > > 80
> > > > > > > > > > 90 for the trans, and I haven't checked on the transfer
case
> > > > yet.
> > > > > > > > Someone
> > > > > > > > > > else told me it might need automatic fluid or a
different
> > type
> > > > of
> > > > > > fluid
> > > > > > > > > for
> > > > > > > > > > the trans so I haven't done anything yet. I don't have
the
> > > > manual of
> > > > > > > > > course.
> > > > > > > > > > What should I do? Any web resource's out there?
> > > > > > > > > >
> > > > > > > > > > Would Daimler Chrysler know? I have been told they only
go
> > > back
> > > > so
> > > > > > many
> > > > > > > > > > years?
> > > > > > > > > >
> > > > > > > > > > Any suggestions would be a great help to me.
> > > > > > > > > >
> > > > > > > > > > -Brian
> > > > > > > > >
> > > > > > > > > DO NOT put 80w-90 in your transmission. It requires a GL3
or
> > GL4
> > > > (low
> > > > > > or
> > > > > > > > no
> > > > > > > > > sulphur) gear oil, other wise the synchros will not be
able to
> > > > > > function
> > > > > > > > > properly and you'll get serious cold gear clash when
shifting.
> > > DC
> > > > has
> > > > > > a
> > > > > > > > > special gear oil for AX15s, plus another for the later
NV3550
> > > used
> > > > in
> > > > > > the
> > > > > > > > > TJs. Check with your local dealer. Alternatively, you can
use
> > > > Redline
> > > > > > MTL.
> > > > > > > > > I've used it in my '94 YJ for years and swear by it.
> > > > > > > > >
> > > > > > > > >
> > > >
> > > >
> > >
> > >
original transmission fluid in my YJ. Coincidence or not, shortly
thereafter the second gear synchro went to hell. By the time I figured out
what had happened the original oil had been picked up by the curbside
recycling people. I got the transmission back to a semblance of normality
by putting Mobil 1 synthetic (75W90? without the limited slip modifier) in
it, but I still have to hit second at just the right rpm, or double clutch
it, to prevent grinding when shifting into that gear.
The original poster should drain his transmission fluid into a clean
container, strain it through a chamois, and pour it back in. ;o) Manual
transmissions "never" get hot enough to burn oil, and therefore the only two
likely sources of contamination are water and metal shavings. The chamois
will take care of the shavings. If the fluid is not cloudy or "milky" then
it doesn't have water in it and he is home free. I suppose you could also
use a time machine and go back far enough to buy some real GL3.
Earle
"Mike Romain" <romainm@sympatico.ca> wrote in message
news:410A80AC.47DA2446@sympatico.ca...
> You are still confusing as ----. ;-)
>
> Now you say it's 'ok' to use redline GL4, but don't do it because it's
> supposed to be GL3 which redline doesn't make, but use redline because
> it is better.
>
> Oh and 'don't use 90 weight because it won't shift, but meanwhile 'you'
> use MTL which 'is' 90 weight which is 'great stuff'.
>
> So just what the heck is it?
>
> 'I' know to use the GL4 'gear oil' for transmissions and to make sure
> it doesn't have the limited slip additive for differentials.
>
> 'I' could only find the GL4 diff fluid once when changing oil so used
> it. My shifter stopped working shortly after.
>
> 'I' then went and found tranny gear oil which only came in a semi
> synthetic at my local parts store, all the 'regular' gear oil had the
> limited slip or friction modifiers in, and now I have a sweet smooth
> shift.
>
> Mike
>
> Jerry McG wrote:
> >
> > Thanks, Jerry. If he's in a cold climate he may want to consider the
70w-80
> > fort improved cold shifting. I put the original fill of Red Line MTL in
my
> > '94 YJs AX15 at 30k miles. I changed it last year as part of the 60k
> > mainenance and noted the drain plug magnet didn't have a single flake of
> > metal on it. Great stuff!
> >
> > The owners manuals for the YJs and XJs through at least '96 also called
for
> > a 75w-90 GL5. I'm not sure when DC caught on and started using the GL3,
but
> > before that MTL was about the only thing available that would stop the
> > synchros.
> >
> > The 75w-90 GL3 sold by DC is quite pricey but works well. I put it in my
'96
> > YJs AX15 three years ago and it immediately eliminated hard cold
shifitng.
> > When I looked this a few months ago the dealer came up with two
different
> > gear oil part 3's, one recommended for the AX15, another for the NV3550.
> > They claim to have used the latter with success in the AX15, but if one
is
> > ordering this stuff might as well get the correct number.
> >
> > "Jerry Bransford" <jerrypb@***.net> wrote in message
> > news:VjjOc.4251$Xn.52@fed1read05...
> > > It calls for a 75W-90 GL-3, and there were some years when the shop
> > manuals
> > > incorrectly called for a 75W-90 GL-5. Redline's MT-90 is a 75W-90
GL-4,
> > MTL
> > > is 70W-80 GL-4. If you go with Redline, MT-90 is the correct
viscosity.
> > >
> > > Jerry
> > > --
> > > Jerry Bransford
> > > PP-ASEL N6TAY
> > > See the Geezer Jeep at
> > > http://members.***.net/jerrypb/
> > > "Jerry McG" <gmcgeorge.remove@frontier.net> wrote in message
> > > news:cecdh601c6u@enews4.newsguy.com...
> > > > Mike,
> > > >
> > > > The original manuals called for a 75w-90 GL5 oil and were corrected
by
> > > tech
> > > > service bulletin years ago. Any 80w-90, even if a lower sulphur GL4,
is
> > > far
> > > > too heavy a lubricant for an AX15 or NV3550. I believe Redline MTL
is a
> > > > 70w-80 GL4.
> > > >
> > > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > news:41096C62.7A63CE5E@sympatico.ca...
> > > > > Sorry if I got mouthy.
> > > > >
> > > > > It is still 80W90 gear oil he needs. You are mixing up terms.
> > > > >
> > > > > The GL rating has nothing to do with the weight of 80W90.
> > > > >
> > > > > Mike
> > > > >
> > > > > Jerry McG wrote:
> > > > > >
> > > > > > Mike,
> > > > > >
> > > > > > I find your description of my assitance to this guy offensive
and
> > > > > > uncharacteristic of you. What I stated is fact. The AX15 can not
> > > > tolerate
> > > > > > 80w-90 GL5 gear oil. DC recommends a special GL3 (no sulphur)
oil
> > > > available
> > > > > > from Jeep dealers. They also make a special GL3 oil for the
NV3550,
> > > > which
> > > > > > has the same issue re: GL5 oils.
> > > > > >
> > > > > > If he uses any form of GL5 gear oil he will experience difficult
to
> > > > > > impossible shifting (esp. in extreme cold) and substantial gear
> > clash.
> > > > Sorry
> > > > > > if my reply offended you, it's just the facts.
> > > > > >
> > > > > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > > > news:41092D32.D9F68E4B@sympatico.ca...
> > > > > > > He just fed you a pile of BS. Not much to thank him for.
> > > > > > >
> > > > > > > Your transfer case takes ATF and your tranny takes 80W90 GL4
'gear
> > > > oil'.
> > > > > > >
> > > > > > > Mike
> > > > > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > > > > 88 Cherokee 235 BFG AT's
> > > > > > >
> > > > > > > Brian Hubley wrote:
> > > > > > > >
> > > > > > > > Thanx Jerry
> > > > > > > >
> > > > > > > > "Jerry McG" <gmcgeorge.remove@frontier.net> wrote in message
> > > > > > > > news:ce9ko42im7@enews1.newsguy.com...
> > > > > > > > >
> > > > > > > > > "Brian Hubley" <brianhubley422@earthlink.net> wrote in
message
> > > > > > > > >
news:7hONc.16881$iK.10045@newsread2.news.atl.earth link.net...
> > > > > > > > > > I have a 91 YJ 4.0L manual with alot of miles I bought
not
> > to
> > > > long
> > > > > > ago.
> > > > > > > > I
> > > > > > > > > > would like to change the fluid in the trans and transfer
> > case.
> > > I
> > > > was
> > > > > > > > told
> > > > > > > > > 80
> > > > > > > > > > 90 for the trans, and I haven't checked on the transfer
case
> > > > yet.
> > > > > > > > Someone
> > > > > > > > > > else told me it might need automatic fluid or a
different
> > type
> > > > of
> > > > > > fluid
> > > > > > > > > for
> > > > > > > > > > the trans so I haven't done anything yet. I don't have
the
> > > > manual of
> > > > > > > > > course.
> > > > > > > > > > What should I do? Any web resource's out there?
> > > > > > > > > >
> > > > > > > > > > Would Daimler Chrysler know? I have been told they only
go
> > > back
> > > > so
> > > > > > many
> > > > > > > > > > years?
> > > > > > > > > >
> > > > > > > > > > Any suggestions would be a great help to me.
> > > > > > > > > >
> > > > > > > > > > -Brian
> > > > > > > > >
> > > > > > > > > DO NOT put 80w-90 in your transmission. It requires a GL3
or
> > GL4
> > > > (low
> > > > > > or
> > > > > > > > no
> > > > > > > > > sulphur) gear oil, other wise the synchros will not be
able to
> > > > > > function
> > > > > > > > > properly and you'll get serious cold gear clash when
shifting.
> > > DC
> > > > has
> > > > > > a
> > > > > > > > > special gear oil for AX15s, plus another for the later
NV3550
> > > used
> > > > in
> > > > > > the
> > > > > > > > > TJs. Check with your local dealer. Alternatively, you can
use
> > > > Redline
> > > > > > MTL.
> > > > > > > > > I've used it in my '94 YJ for years and swear by it.
> > > > > > > > >
> > > > > > > > >
> > > >
> > > >
> > >
> > >
07-31-2004, 12:43 AM
#58
Guest
Posts: n/a
Re: Correct Trans and diff fluid for a YJ
http://www.vtr.org/maintain/oil-overview.html
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
Jerry McG wrote:
>
> The "cold" rating of an oil (i.e., "70w-x") is an oils actual petroleum
> viscosity, the other rating (i,e., "Xw-90") is its "petroleum equivalent"
> rating at average operating temp and is simply a rating based upon the
> effectiveness of its additives.
>
> Thus, a 75w-90 is actually a thin 75 weight oil when cold, but becomes the
> "equivalent" of a 90 weight oil when hot. Same with multi-vis motor oil.
>
> Most wear and shifting problems occur when a unit is cold. Thus, because of
> it's superior flowing capabilities, a lighter oil is best under that
> condition. However, under higher temps and load a higher viscosity (90w) is
> better. To get the best of both worlds petroleum engineers start with a
> light weight base stock, then introduce additives that increase its
> capabilities under heat and pressure.
>
> The sulphur content of gear oils adds a complication: higher sulphur content
> (i.e., GL5) in a gear oil is an advantage when the oil is under pressure,
> such as when it's squeezed between a ring and pinion. Unfortunately, that
> very advantage becomes a disadvantage re: synchronizer rings, which must
> have enough friction capability to stop spinning gears to avoid gear clash.
> High sulphur content oils compromise that function. Thus, engineers specify
> lower sulphur (GL3 or CL4) oil in transmissions to keep cold synchros happy.
>
> This stuff is really easy to see. Compare a bit of 75w-90 gear oil to
> straight 90w and it's easily apparent which is the lighter oil. You can also
> easily smell the difference between a GL5 and GL3 oil, the GL5 stuff stinks
> of rotten eggs to high heaven, the GL3 stuff smells more like motor oil.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
Jerry McG wrote:
>
> The "cold" rating of an oil (i.e., "70w-x") is an oils actual petroleum
> viscosity, the other rating (i,e., "Xw-90") is its "petroleum equivalent"
> rating at average operating temp and is simply a rating based upon the
> effectiveness of its additives.
>
> Thus, a 75w-90 is actually a thin 75 weight oil when cold, but becomes the
> "equivalent" of a 90 weight oil when hot. Same with multi-vis motor oil.
>
> Most wear and shifting problems occur when a unit is cold. Thus, because of
> it's superior flowing capabilities, a lighter oil is best under that
> condition. However, under higher temps and load a higher viscosity (90w) is
> better. To get the best of both worlds petroleum engineers start with a
> light weight base stock, then introduce additives that increase its
> capabilities under heat and pressure.
>
> The sulphur content of gear oils adds a complication: higher sulphur content
> (i.e., GL5) in a gear oil is an advantage when the oil is under pressure,
> such as when it's squeezed between a ring and pinion. Unfortunately, that
> very advantage becomes a disadvantage re: synchronizer rings, which must
> have enough friction capability to stop spinning gears to avoid gear clash.
> High sulphur content oils compromise that function. Thus, engineers specify
> lower sulphur (GL3 or CL4) oil in transmissions to keep cold synchros happy.
>
> This stuff is really easy to see. Compare a bit of 75w-90 gear oil to
> straight 90w and it's easily apparent which is the lighter oil. You can also
> easily smell the difference between a GL5 and GL3 oil, the GL5 stuff stinks
> of rotten eggs to high heaven, the GL3 stuff smells more like motor oil.
07-31-2004, 12:43 AM
#59
Guest
Posts: n/a
Re: Correct Trans and diff fluid for a YJ
http://www.vtr.org/maintain/oil-overview.html
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
Jerry McG wrote:
>
> The "cold" rating of an oil (i.e., "70w-x") is an oils actual petroleum
> viscosity, the other rating (i,e., "Xw-90") is its "petroleum equivalent"
> rating at average operating temp and is simply a rating based upon the
> effectiveness of its additives.
>
> Thus, a 75w-90 is actually a thin 75 weight oil when cold, but becomes the
> "equivalent" of a 90 weight oil when hot. Same with multi-vis motor oil.
>
> Most wear and shifting problems occur when a unit is cold. Thus, because of
> it's superior flowing capabilities, a lighter oil is best under that
> condition. However, under higher temps and load a higher viscosity (90w) is
> better. To get the best of both worlds petroleum engineers start with a
> light weight base stock, then introduce additives that increase its
> capabilities under heat and pressure.
>
> The sulphur content of gear oils adds a complication: higher sulphur content
> (i.e., GL5) in a gear oil is an advantage when the oil is under pressure,
> such as when it's squeezed between a ring and pinion. Unfortunately, that
> very advantage becomes a disadvantage re: synchronizer rings, which must
> have enough friction capability to stop spinning gears to avoid gear clash.
> High sulphur content oils compromise that function. Thus, engineers specify
> lower sulphur (GL3 or CL4) oil in transmissions to keep cold synchros happy.
>
> This stuff is really easy to see. Compare a bit of 75w-90 gear oil to
> straight 90w and it's easily apparent which is the lighter oil. You can also
> easily smell the difference between a GL5 and GL3 oil, the GL5 stuff stinks
> of rotten eggs to high heaven, the GL3 stuff smells more like motor oil.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
Jerry McG wrote:
>
> The "cold" rating of an oil (i.e., "70w-x") is an oils actual petroleum
> viscosity, the other rating (i,e., "Xw-90") is its "petroleum equivalent"
> rating at average operating temp and is simply a rating based upon the
> effectiveness of its additives.
>
> Thus, a 75w-90 is actually a thin 75 weight oil when cold, but becomes the
> "equivalent" of a 90 weight oil when hot. Same with multi-vis motor oil.
>
> Most wear and shifting problems occur when a unit is cold. Thus, because of
> it's superior flowing capabilities, a lighter oil is best under that
> condition. However, under higher temps and load a higher viscosity (90w) is
> better. To get the best of both worlds petroleum engineers start with a
> light weight base stock, then introduce additives that increase its
> capabilities under heat and pressure.
>
> The sulphur content of gear oils adds a complication: higher sulphur content
> (i.e., GL5) in a gear oil is an advantage when the oil is under pressure,
> such as when it's squeezed between a ring and pinion. Unfortunately, that
> very advantage becomes a disadvantage re: synchronizer rings, which must
> have enough friction capability to stop spinning gears to avoid gear clash.
> High sulphur content oils compromise that function. Thus, engineers specify
> lower sulphur (GL3 or CL4) oil in transmissions to keep cold synchros happy.
>
> This stuff is really easy to see. Compare a bit of 75w-90 gear oil to
> straight 90w and it's easily apparent which is the lighter oil. You can also
> easily smell the difference between a GL5 and GL3 oil, the GL5 stuff stinks
> of rotten eggs to high heaven, the GL3 stuff smells more like motor oil.
07-31-2004, 12:43 AM
#60
Guest
Posts: n/a
Re: Correct Trans and diff fluid for a YJ
http://www.vtr.org/maintain/oil-overview.html
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
Jerry McG wrote:
>
> The "cold" rating of an oil (i.e., "70w-x") is an oils actual petroleum
> viscosity, the other rating (i,e., "Xw-90") is its "petroleum equivalent"
> rating at average operating temp and is simply a rating based upon the
> effectiveness of its additives.
>
> Thus, a 75w-90 is actually a thin 75 weight oil when cold, but becomes the
> "equivalent" of a 90 weight oil when hot. Same with multi-vis motor oil.
>
> Most wear and shifting problems occur when a unit is cold. Thus, because of
> it's superior flowing capabilities, a lighter oil is best under that
> condition. However, under higher temps and load a higher viscosity (90w) is
> better. To get the best of both worlds petroleum engineers start with a
> light weight base stock, then introduce additives that increase its
> capabilities under heat and pressure.
>
> The sulphur content of gear oils adds a complication: higher sulphur content
> (i.e., GL5) in a gear oil is an advantage when the oil is under pressure,
> such as when it's squeezed between a ring and pinion. Unfortunately, that
> very advantage becomes a disadvantage re: synchronizer rings, which must
> have enough friction capability to stop spinning gears to avoid gear clash.
> High sulphur content oils compromise that function. Thus, engineers specify
> lower sulphur (GL3 or CL4) oil in transmissions to keep cold synchros happy.
>
> This stuff is really easy to see. Compare a bit of 75w-90 gear oil to
> straight 90w and it's easily apparent which is the lighter oil. You can also
> easily smell the difference between a GL5 and GL3 oil, the GL5 stuff stinks
> of rotten eggs to high heaven, the GL3 stuff smells more like motor oil.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
Jerry McG wrote:
>
> The "cold" rating of an oil (i.e., "70w-x") is an oils actual petroleum
> viscosity, the other rating (i,e., "Xw-90") is its "petroleum equivalent"
> rating at average operating temp and is simply a rating based upon the
> effectiveness of its additives.
>
> Thus, a 75w-90 is actually a thin 75 weight oil when cold, but becomes the
> "equivalent" of a 90 weight oil when hot. Same with multi-vis motor oil.
>
> Most wear and shifting problems occur when a unit is cold. Thus, because of
> it's superior flowing capabilities, a lighter oil is best under that
> condition. However, under higher temps and load a higher viscosity (90w) is
> better. To get the best of both worlds petroleum engineers start with a
> light weight base stock, then introduce additives that increase its
> capabilities under heat and pressure.
>
> The sulphur content of gear oils adds a complication: higher sulphur content
> (i.e., GL5) in a gear oil is an advantage when the oil is under pressure,
> such as when it's squeezed between a ring and pinion. Unfortunately, that
> very advantage becomes a disadvantage re: synchronizer rings, which must
> have enough friction capability to stop spinning gears to avoid gear clash.
> High sulphur content oils compromise that function. Thus, engineers specify
> lower sulphur (GL3 or CL4) oil in transmissions to keep cold synchros happy.
>
> This stuff is really easy to see. Compare a bit of 75w-90 gear oil to
> straight 90w and it's easily apparent which is the lighter oil. You can also
> easily smell the difference between a GL5 and GL3 oil, the GL5 stuff stinks
> of rotten eggs to high heaven, the GL3 stuff smells more like motor oil.