Thinner oil could drain from the mains, while parked. Thicker oil than
warranted may not be pumped to the bearings fast enough. Oil pressure
gauges measure the pressure in the oil galleries, not at the bearings where
it counts. Unless you have a race prepared engine with non-stock bearing
clearances, and you know exactly what you are doing, it is best to use the
oil recommended for street use. For most of the vehicles discussed here,
that is 10W30.

Earle

"L.W. (ßill) ------ III" <----------@***.net> wrote in message
news:43DFBC6F.9A970306@***.net...
> Hi Mike,
> Thinner oil will drain from the mains, while parked. Usually you
> hear the telltale low knock noise about two or three times before the
> oil separates the metals.
> God Bless America, Bill O|||||||O
> mailto:-------------------- http://www.----------.com/
>
> Mike Romain wrote:
> >
> > Good question. It also appears to burn up or get used faster. When
> > used it physically 'feels' thinner too.
> >
> > Maybe that is it. My mechanical oil pressure gauge does read lower when
> > the oil level get low. Every time. I can look at it and know if I will
> > be down a liter. Could be it allows the engine to run hotter??
> >
> > Don't really know.
> >
> > Mike

 

Thinner oil could drain from the mains, while parked. Thicker oil than
warranted may not be pumped to the bearings fast enough. Oil pressure
gauges measure the pressure in the oil galleries, not at the bearings where
it counts. Unless you have a race prepared engine with non-stock bearing
clearances, and you know exactly what you are doing, it is best to use the
oil recommended for street use. For most of the vehicles discussed here,
that is 10W30.

Earle

"L.W. (ßill) ------ III" <----------@***.net> wrote in message
news:43DFBC6F.9A970306@***.net...
> Hi Mike,
> Thinner oil will drain from the mains, while parked. Usually you
> hear the telltale low knock noise about two or three times before the
> oil separates the metals.
> God Bless America, Bill O|||||||O
> mailto:-------------------- http://www.----------.com/
>
> Mike Romain wrote:
> >
> > Good question. It also appears to burn up or get used faster. When
> > used it physically 'feels' thinner too.
> >
> > Maybe that is it. My mechanical oil pressure gauge does read lower when
> > the oil level get low. Every time. I can look at it and know if I will
> > be down a liter. Could be it allows the engine to run hotter??
> >
> > Don't really know.
> >
> > Mike

 

Jeep dealers here use Mobil 1 which is graded as a 5w 40. You don't get
anything w 30 here.

Dave Milne, Scotland
'91 Grand Wagoneer, '99 TJ

"Mike Romain" <romainm@sympatico.ca> wrote in message
news:43DF8FC4.8B76F631@sympatico.ca...
> I don't understand why you folks would use an oil that technically could
> void the engine warranty?
>
> If the book calls for 10W30, then using 5W30 is just plain asking for
> trouble and extra wear due to the thin oil not lubricating or 'staying
> in' the gaps between friction surfaces.
>
> I can see the difference in my mechanical oil pressure gauge when thin
> oil is used or my oil gets old and thin.
>
> I used 5W30 once because I got a 'deal' on it. I very quickly changed
> it back to the proper oil because the pressure was over 5 psi lower on
> the highway and especially at idle, it dived really low when hot.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's
> Canadian Off Road Trips Photos: Non members can still view!
> Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
> (More Off Road album links at bottom of the view page)
>
> Jerry Bransford wrote:
> >
> > A long talk with a Mobil Oil engineer at a trade show cured a similar
> > long-standing fear I had of 5W-30.
> >
> > Vito wrote:
> > > "jeepney driver via CarKB.com" <u17884@uwe> wrote
> > >
> > >>i'm using mobil 5w-30 synthetic oil .....
> > >
> > >
> > > I'm spookey of 5w-30 in anything but sub-zero weather.
> > >
> > > Returning from Long Beach to San Diego one hot afternoon I parked my
Ford (350C
> > > motor) for the night. The next AM it turned over a rev then there was
a loud pop
> > > and it began running on 6 cylinders. Investigation showed that two
hydraulic
> > > lifters had collapsed over night allowing the push rods to come out of
the cup
> > > when the motor was cranked. Like you I was using 5w-30 synthetic
(Mobile 1).
> > > Not any more.
> > >
> > >
> >
> > --
> > Jerry Bransford
> > PP-ASEL N6TAY
> > See the Geezer Jeep at
> > http://members.***.net/jerrypb/

 

Jeep dealers here use Mobil 1 which is graded as a 5w 40. You don't get
anything w 30 here.

Dave Milne, Scotland
'91 Grand Wagoneer, '99 TJ

"Mike Romain" <romainm@sympatico.ca> wrote in message
news:43DF8FC4.8B76F631@sympatico.ca...
> I don't understand why you folks would use an oil that technically could
> void the engine warranty?
>
> If the book calls for 10W30, then using 5W30 is just plain asking for
> trouble and extra wear due to the thin oil not lubricating or 'staying
> in' the gaps between friction surfaces.
>
> I can see the difference in my mechanical oil pressure gauge when thin
> oil is used or my oil gets old and thin.
>
> I used 5W30 once because I got a 'deal' on it. I very quickly changed
> it back to the proper oil because the pressure was over 5 psi lower on
> the highway and especially at idle, it dived really low when hot.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's
> Canadian Off Road Trips Photos: Non members can still view!
> Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
> (More Off Road album links at bottom of the view page)
>
> Jerry Bransford wrote:
> >
> > A long talk with a Mobil Oil engineer at a trade show cured a similar
> > long-standing fear I had of 5W-30.
> >
> > Vito wrote:
> > > "jeepney driver via CarKB.com" <u17884@uwe> wrote
> > >
> > >>i'm using mobil 5w-30 synthetic oil .....
> > >
> > >
> > > I'm spookey of 5w-30 in anything but sub-zero weather.
> > >
> > > Returning from Long Beach to San Diego one hot afternoon I parked my
Ford (350C
> > > motor) for the night. The next AM it turned over a rev then there was
a loud pop
> > > and it began running on 6 cylinders. Investigation showed that two
hydraulic
> > > lifters had collapsed over night allowing the push rods to come out of
the cup
> > > when the motor was cranked. Like you I was using 5w-30 synthetic
(Mobile 1).
> > > Not any more.
> > >
> > >
> >
> > --
> > Jerry Bransford
> > PP-ASEL N6TAY
> > See the Geezer Jeep at
> > http://members.***.net/jerrypb/

 

Jeep dealers here use Mobil 1 which is graded as a 5w 40. You don't get
anything w 30 here.

Dave Milne, Scotland
'91 Grand Wagoneer, '99 TJ

"Mike Romain" <romainm@sympatico.ca> wrote in message
news:43DF8FC4.8B76F631@sympatico.ca...
> I don't understand why you folks would use an oil that technically could
> void the engine warranty?
>
> If the book calls for 10W30, then using 5W30 is just plain asking for
> trouble and extra wear due to the thin oil not lubricating or 'staying
> in' the gaps between friction surfaces.
>
> I can see the difference in my mechanical oil pressure gauge when thin
> oil is used or my oil gets old and thin.
>
> I used 5W30 once because I got a 'deal' on it. I very quickly changed
> it back to the proper oil because the pressure was over 5 psi lower on
> the highway and especially at idle, it dived really low when hot.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's
> Canadian Off Road Trips Photos: Non members can still view!
> Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
> (More Off Road album links at bottom of the view page)
>
> Jerry Bransford wrote:
> >
> > A long talk with a Mobil Oil engineer at a trade show cured a similar
> > long-standing fear I had of 5W-30.
> >
> > Vito wrote:
> > > "jeepney driver via CarKB.com" <u17884@uwe> wrote
> > >
> > >>i'm using mobil 5w-30 synthetic oil .....
> > >
> > >
> > > I'm spookey of 5w-30 in anything but sub-zero weather.
> > >
> > > Returning from Long Beach to San Diego one hot afternoon I parked my
Ford (350C
> > > motor) for the night. The next AM it turned over a rev then there was
a loud pop
> > > and it began running on 6 cylinders. Investigation showed that two
hydraulic
> > > lifters had collapsed over night allowing the push rods to come out of
the cup
> > > when the motor was cranked. Like you I was using 5w-30 synthetic
(Mobile 1).
> > > Not any more.
> > >
> > >
> >
> > --
> > Jerry Bransford
> > PP-ASEL N6TAY
> > See the Geezer Jeep at
> > http://members.***.net/jerrypb/

 

What oil is called for in your owner's manuals?

"Dave Milne" <jeep@_nospam_milne.info> wrote in message
news:gfRDf.12889$wl.1772@text.news.blueyonder.co.u k...
> Jeep dealers here use Mobil 1 which is graded as a 5w 40. You don't get
> anything w 30 here.
>
> Dave Milne, Scotland
> '91 Grand Wagoneer, '99 TJ

 

What oil is called for in your owner's manuals?

"Dave Milne" <jeep@_nospam_milne.info> wrote in message
news:gfRDf.12889$wl.1772@text.news.blueyonder.co.u k...
> Jeep dealers here use Mobil 1 which is graded as a 5w 40. You don't get
> anything w 30 here.
>
> Dave Milne, Scotland
> '91 Grand Wagoneer, '99 TJ

 

What oil is called for in your owner's manuals?

"Dave Milne" <jeep@_nospam_milne.info> wrote in message
news:gfRDf.12889$wl.1772@text.news.blueyonder.co.u k...
> Jeep dealers here use Mobil 1 which is graded as a 5w 40. You don't get
> anything w 30 here.
>
> Dave Milne, Scotland
> '91 Grand Wagoneer, '99 TJ

 

You better re-read your WJ owner's manual. For my 2002 WJ with the 4.7L
engine, I just re-verified that the owners manual says 5W-30 can be used
from below zero to 100f.

Jerry
billy ray wrote:
> Please define "Temperate Conditions".
>
> My XJ manual and my WJ manual clearly indicate with a chart to use 5w-30
> ONLY when the weather is below freezing (32F) and the "Preferred" weight is
> 10w-30 for weather at 0F and above.
>
> That being said the OP lives in San Diego. I will quote from the NOAA
> http://www.wrh.noaa.gov/sgx/climate/san-san-month.htm
>
> " JANUARY WEATHER IN SAN DIEGO
>
> JANUARY IS USUALLY THE COLDEST MONTH OF THE YEAR IN SAN DIEGO AND THE ONLY
> MONTH WHEN TEMPERATURES BELOW THE FREEZING POINT WERE EXPERIENCED AT THE
> NATIONAL WEATHER SERVICE. ONLY ON 9 DAYS HAS A READING OF 32 DEGREES OR
> BELOW BEEN RECORDED SINCE RECORDS BEGAN IN 1872 WITH THE ABSOLUTE LOW OF 25
> DEGREES ON JANUARY 7,
> 1913. THE AVERAGE MINIMUM TEMPERATURE FOR THE MONTH IS 48.9 DEGREES, THE
> AVERAGE MAXIMUM 65.9 DEGREES AND THE MEAN 57.4 DEGREES. DAYTIME READINGS
> OFTEN REACH 70 DEGREES AND OCCASIONALLY 80 DEGREES AND ON JANUARY 10 IN 1953
> ROSE TO A HIGH OF 88 DEGREES."
>
> In the past 134 years there have been a total of 9 days where the use of
> 5w-30 would be in the allowed range.
>
> Will lower weight (5w vs. 10w) multi-viscosity oil lead to parts failures?
> I don't know and I doubt it would in a properly maintained motor in good
> condition but why intentionally use an improper weight oil?
>
> It took me a long time to change from my belief that in regard to motor oil
> that thicker was better. I am sure that is based on my age and the vehicles
> of that era. I am from the pre-ASE era, my mechanics accreditation was
> based on written and practical exam from Chrysler.
>
> The first step for oil burning, consumption, leaking, and low pressure was
> to use thicker oil as that usually "cured" the problem. When GM first
> started recommending 5w-30 oil in the 80s it took the motoring public and
> professionals by surprise as the trend was the other direction. The biggest
> seller by far was 10w-40 and the 15w-40 and 20w-50 weights sales were
> rising. I personally believed in using straight 30 weight diesel oil
> (Pennzoil Series 3) in the summer to clean sludge from internal engine
> parts.
>
> This is, however, all historic information jumbled in the dusty corners of
> my memory. Newer automobile oils, especially the synthetics, contain
> detergents that actually work and offer superior lubrication and protection
> for engine parts. In regard to specific applications my concern is that some
> oils may be too thick. I used 5w-30 in my twin turbo Audi because 0w-30 was
> unavailable locally!
>
> As mentioned above.... why specifically choose to use an oil thinner than
> recommended?
>
>
>
> "Jerry Bransford" <jerrypb@***.net> wrote in message
> news:gBMDf.54991$V.41970@fed1read04...
>
>>Mike, my TJ's owners manual specifically includes 5W-30 as a suitable oil
>>for even temperate conditions in addition to the usual 10W-30. :)
>>
>>Mike Romain wrote:
>>
>>>I don't understand why you folks would use an oil that technically could
>>>void the engine warranty?
>>>
>>>If the book calls for 10W30, then using 5W30 is just plain asking for
>>>trouble and extra wear due to the thin oil not lubricating or 'staying
>>>in' the gaps between friction surfaces.
>>>
>>>I can see the difference in my mechanical oil pressure gauge when thin
>>>oil is used or my oil gets old and thin.
>>>
>>>I used 5W30 once because I got a 'deal' on it. I very quickly changed
>>>it back to the proper oil because the pressure was over 5 psi lower on
>>>the highway and especially at idle, it dived really low when hot.
>>>
>>>Mike
>>>86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>>>88 Cherokee 235 BFG AT's
>>>Canadian Off Road Trips Photos: Non members can still view!
>>>Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
>>>(More Off Road album links at bottom of the view page) Jerry Bransford
>>>wrote:
>>>
>>>
>>>>A long talk with a Mobil Oil engineer at a trade show cured a similar
>>>>long-standing fear I had of 5W-30.
>>>>
>>>>Vito wrote:
>>>>
>>>>
>>>>>"jeepney driver via CarKB.com" <u17884@uwe> wrote
>>>>>
>>>>>
>>>>>
>>>>>>i'm using mobil 5w-30 synthetic oil .....
>>>>>
>>>>>
>>>>>I'm spookey of 5w-30 in anything but sub-zero weather.
>>>>>
>>>>>Returning from Long Beach to San Diego one hot afternoon I parked my
>>>>>Ford (350C
>>>>>motor) for the night. The next AM it turned over a rev then there was a
>>>>>loud pop
>>>>>and it began running on 6 cylinders. Investigation showed that two
>>>>>hydraulic
>>>>>lifters had collapsed over night allowing the push rods to come out of
>>>>>the cup
>>>>>when the motor was cranked. Like you I was using 5w-30 synthetic (Mobile
>>>>>1).
>>>>>Not any more.
>>>>>
>>>>>
>>>>
>>>>--
>>>>Jerry Bransford
>>>>PP-ASEL N6TAY
>>>>See the Geezer Jeep at
>>>>http://members.***.net/jerrypb/
>>
>>--
>>Jerry Bransford
>>PP-ASEL N6TAY
>>See the Geezer Jeep at
>>http://members.***.net/jerrypb/
>
>
>

--
Jerry Bransford
PP-ASEL N6TAY
See the Geezer Jeep at
http://members.***.net/jerrypb/

 

You better re-read your WJ owner's manual. For my 2002 WJ with the 4.7L
engine, I just re-verified that the owners manual says 5W-30 can be used
from below zero to 100f.

Jerry
billy ray wrote:
> Please define "Temperate Conditions".
>
> My XJ manual and my WJ manual clearly indicate with a chart to use 5w-30
> ONLY when the weather is below freezing (32F) and the "Preferred" weight is
> 10w-30 for weather at 0F and above.
>
> That being said the OP lives in San Diego. I will quote from the NOAA
> http://www.wrh.noaa.gov/sgx/climate/san-san-month.htm
>
> " JANUARY WEATHER IN SAN DIEGO
>
> JANUARY IS USUALLY THE COLDEST MONTH OF THE YEAR IN SAN DIEGO AND THE ONLY
> MONTH WHEN TEMPERATURES BELOW THE FREEZING POINT WERE EXPERIENCED AT THE
> NATIONAL WEATHER SERVICE. ONLY ON 9 DAYS HAS A READING OF 32 DEGREES OR
> BELOW BEEN RECORDED SINCE RECORDS BEGAN IN 1872 WITH THE ABSOLUTE LOW OF 25
> DEGREES ON JANUARY 7,
> 1913. THE AVERAGE MINIMUM TEMPERATURE FOR THE MONTH IS 48.9 DEGREES, THE
> AVERAGE MAXIMUM 65.9 DEGREES AND THE MEAN 57.4 DEGREES. DAYTIME READINGS
> OFTEN REACH 70 DEGREES AND OCCASIONALLY 80 DEGREES AND ON JANUARY 10 IN 1953
> ROSE TO A HIGH OF 88 DEGREES."
>
> In the past 134 years there have been a total of 9 days where the use of
> 5w-30 would be in the allowed range.
>
> Will lower weight (5w vs. 10w) multi-viscosity oil lead to parts failures?
> I don't know and I doubt it would in a properly maintained motor in good
> condition but why intentionally use an improper weight oil?
>
> It took me a long time to change from my belief that in regard to motor oil
> that thicker was better. I am sure that is based on my age and the vehicles
> of that era. I am from the pre-ASE era, my mechanics accreditation was
> based on written and practical exam from Chrysler.
>
> The first step for oil burning, consumption, leaking, and low pressure was
> to use thicker oil as that usually "cured" the problem. When GM first
> started recommending 5w-30 oil in the 80s it took the motoring public and
> professionals by surprise as the trend was the other direction. The biggest
> seller by far was 10w-40 and the 15w-40 and 20w-50 weights sales were
> rising. I personally believed in using straight 30 weight diesel oil
> (Pennzoil Series 3) in the summer to clean sludge from internal engine
> parts.
>
> This is, however, all historic information jumbled in the dusty corners of
> my memory. Newer automobile oils, especially the synthetics, contain
> detergents that actually work and offer superior lubrication and protection
> for engine parts. In regard to specific applications my concern is that some
> oils may be too thick. I used 5w-30 in my twin turbo Audi because 0w-30 was
> unavailable locally!
>
> As mentioned above.... why specifically choose to use an oil thinner than
> recommended?
>
>
>
> "Jerry Bransford" <jerrypb@***.net> wrote in message
> news:gBMDf.54991$V.41970@fed1read04...
>
>>Mike, my TJ's owners manual specifically includes 5W-30 as a suitable oil
>>for even temperate conditions in addition to the usual 10W-30. :)
>>
>>Mike Romain wrote:
>>
>>>I don't understand why you folks would use an oil that technically could
>>>void the engine warranty?
>>>
>>>If the book calls for 10W30, then using 5W30 is just plain asking for
>>>trouble and extra wear due to the thin oil not lubricating or 'staying
>>>in' the gaps between friction surfaces.
>>>
>>>I can see the difference in my mechanical oil pressure gauge when thin
>>>oil is used or my oil gets old and thin.
>>>
>>>I used 5W30 once because I got a 'deal' on it. I very quickly changed
>>>it back to the proper oil because the pressure was over 5 psi lower on
>>>the highway and especially at idle, it dived really low when hot.
>>>
>>>Mike
>>>86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>>>88 Cherokee 235 BFG AT's
>>>Canadian Off Road Trips Photos: Non members can still view!
>>>Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
>>>(More Off Road album links at bottom of the view page) Jerry Bransford
>>>wrote:
>>>
>>>
>>>>A long talk with a Mobil Oil engineer at a trade show cured a similar
>>>>long-standing fear I had of 5W-30.
>>>>
>>>>Vito wrote:
>>>>
>>>>
>>>>>"jeepney driver via CarKB.com" <u17884@uwe> wrote
>>>>>
>>>>>
>>>>>
>>>>>>i'm using mobil 5w-30 synthetic oil .....
>>>>>
>>>>>
>>>>>I'm spookey of 5w-30 in anything but sub-zero weather.
>>>>>
>>>>>Returning from Long Beach to San Diego one hot afternoon I parked my
>>>>>Ford (350C
>>>>>motor) for the night. The next AM it turned over a rev then there was a
>>>>>loud pop
>>>>>and it began running on 6 cylinders. Investigation showed that two
>>>>>hydraulic
>>>>>lifters had collapsed over night allowing the push rods to come out of
>>>>>the cup
>>>>>when the motor was cranked. Like you I was using 5w-30 synthetic (Mobile
>>>>>1).
>>>>>Not any more.
>>>>>
>>>>>
>>>>
>>>>--
>>>>Jerry Bransford
>>>>PP-ASEL N6TAY
>>>>See the Geezer Jeep at
>>>>http://members.***.net/jerrypb/
>>
>>--
>>Jerry Bransford
>>PP-ASEL N6TAY
>>See the Geezer Jeep at
>>http://members.***.net/jerrypb/
>
>
>

--
Jerry Bransford
PP-ASEL N6TAY
See the Geezer Jeep at
http://members.***.net/jerrypb/