ACCURATE SPEEDOMETER?
09-17-2007, 11:17 AM
#21
Guest
Posts: n/a
Re: ACCURATE SPEEDOMETER?
Tracie wrote:
> Hello all. I have a 2006 Wrangler X with 6 speed manual tranny, 3.07
> gearing, and D30 front/35 rear. I recently upgraded my tires from the
> stock 215/75/15 to 31/10.5/15 BFG All Terrain T/A KO. I am looking
> for a reliable way to tell if my speedometer is off at all with the
> tire upgrade. I do not have access to a GPS system. What I HAVE done
> is to use the tripometer (with tenths), and hold steady at 60 mph (my
> speedometer said 60) for one mile while watching my clock. I am
> EXTREMELY close to going 1 mile in 1 minute by using this method. Is
> this reliable to tell whether or not my speedometer is dead on? I
> have NOT changed the speedometer gear yet, or had the computer changed
> to reflect the larger sized tires. Also, I am not using my OD (6th)
> much on the highway, but when I get up to 65 (the speedometer says
> 65), I am running at about 2500 rpms in 5th. Is this bad, or should I
> be shifting into the OD (6th)? I do fine with 1st through 5th. Just
> not sure what speed or what rpms I should be using 6th. Any help is
> really appreciated.
>
The (ones that have posed here) older TJ speedometers became correct
when 31" tire were put on.
Your mile per minute is a good base to tell it is close.
The only other way is to find a measured mile or a friend with a GPS or
even ask a cop to pace you because 'you just got new tires and don't
want to break the law'. Only a cop's speedometer would be reliable for
this, cars can be off too according to tire size.
I find 'my' engine 'much' prefers to be running at 2300-2500 rpm on the
highway which I get with my 4th gear. (have 33's and 3.31 gears) That
rpm gives me good throttle control and prevents engine lugging. I also
get a pretty stable 11L/100km or 23 mpg running there.
If I go to overdrive or 5th gear, the rpm drops to 1750 or so at 65 mph
which makes for the need of the full gas pedal travel to adjust speed or
hold a hill or wind vs a twitch of the pedal in 4th. This low rpm drops
my gas mileage by at least 5-8 mpg.
You can find out easy. Just compare gas mileages when using only 5th on
the highway and when using 6th mostly. I have one trip I do lots to get
bush camping which is 201 km from gas station to gas station so I have
an easy check point.
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's - Gone to the rust pile...
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)
> Hello all. I have a 2006 Wrangler X with 6 speed manual tranny, 3.07
> gearing, and D30 front/35 rear. I recently upgraded my tires from the
> stock 215/75/15 to 31/10.5/15 BFG All Terrain T/A KO. I am looking
> for a reliable way to tell if my speedometer is off at all with the
> tire upgrade. I do not have access to a GPS system. What I HAVE done
> is to use the tripometer (with tenths), and hold steady at 60 mph (my
> speedometer said 60) for one mile while watching my clock. I am
> EXTREMELY close to going 1 mile in 1 minute by using this method. Is
> this reliable to tell whether or not my speedometer is dead on? I
> have NOT changed the speedometer gear yet, or had the computer changed
> to reflect the larger sized tires. Also, I am not using my OD (6th)
> much on the highway, but when I get up to 65 (the speedometer says
> 65), I am running at about 2500 rpms in 5th. Is this bad, or should I
> be shifting into the OD (6th)? I do fine with 1st through 5th. Just
> not sure what speed or what rpms I should be using 6th. Any help is
> really appreciated.
>
The (ones that have posed here) older TJ speedometers became correct
when 31" tire were put on.
Your mile per minute is a good base to tell it is close.
The only other way is to find a measured mile or a friend with a GPS or
even ask a cop to pace you because 'you just got new tires and don't
want to break the law'. Only a cop's speedometer would be reliable for
this, cars can be off too according to tire size.
I find 'my' engine 'much' prefers to be running at 2300-2500 rpm on the
highway which I get with my 4th gear. (have 33's and 3.31 gears) That
rpm gives me good throttle control and prevents engine lugging. I also
get a pretty stable 11L/100km or 23 mpg running there.
If I go to overdrive or 5th gear, the rpm drops to 1750 or so at 65 mph
which makes for the need of the full gas pedal travel to adjust speed or
hold a hill or wind vs a twitch of the pedal in 4th. This low rpm drops
my gas mileage by at least 5-8 mpg.
You can find out easy. Just compare gas mileages when using only 5th on
the highway and when using 6th mostly. I have one trip I do lots to get
bush camping which is 201 km from gas station to gas station so I have
an easy check point.
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's - Gone to the rust pile...
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)
09-17-2007, 11:26 AM
#22
Guest
Posts: n/a
Re: ACCURATE SPEEDOMETER?
On Sep 17, 11:17 am, Mike Romain <roma...@sympatico.ca> wrote:
> Tracie wrote:
> > Hello all. I have a 2006 Wrangler X with 6 speed manual tranny, 3.07
> > gearing, and D30 front/35 rear. I recently upgraded my tires from the
> > stock 215/75/15 to 31/10.5/15 BFG All Terrain T/A KO. I am looking
> > for a reliable way to tell if my speedometer is off at all with the
> > tire upgrade. I do not have access to a GPS system. What I HAVE done
> > is to use the tripometer (with tenths), and hold steady at 60 mph (my
> > speedometer said 60) for one mile while watching my clock. I am
> > EXTREMELY close to going 1 mile in 1 minute by using this method. Is
> > this reliable to tell whether or not my speedometer is dead on? I
> > have NOT changed the speedometer gear yet, or had the computer changed
> > to reflect the larger sized tires. Also, I am not using my OD (6th)
> > much on the highway, but when I get up to 65 (the speedometer says
> > 65), I am running at about 2500 rpms in 5th. Is this bad, or should I
> > be shifting into the OD (6th)? I do fine with 1st through 5th. Just
> > not sure what speed or what rpms I should be using 6th. Any help is
> > really appreciated.
>
> The (ones that have posed here) older TJ speedometers became correct
> when 31" tire were put on.
>
> Your mile per minute is a good base to tell it is close.
>
> The only other way is to find a measured mile or a friend with a GPS or
> even ask a cop to pace you because 'you just got new tires and don't
> want to break the law'. Only a cop's speedometer would be reliable for
> this, cars can be off too according to tire size.
>
> I find 'my' engine 'much' prefers to be running at 2300-2500 rpm on the
> highway which I get with my 4th gear. (have 33's and 3.31 gears) That
> rpm gives me good throttle control and prevents engine lugging. I also
> get a pretty stable 11L/100km or 23 mpg running there.
>
> If I go to overdrive or 5th gear, the rpm drops to 1750 or so at 65 mph
> which makes for the need of the full gas pedal travel to adjust speed or
> hold a hill or wind vs a twitch of the pedal in 4th. This low rpm drops
> my gas mileage by at least 5-8 mpg.
>
> You can find out easy. Just compare gas mileages when using only 5th on
> the highway and when using 6th mostly. I have one trip I do lots to get
> bush camping which is 201 km from gas station to gas station so I have
> an easy check point.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> Canadian Off Road Trips Photos: Non members can still view!
> Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
> (More Off Road album links at bottom of the view page)- Hide quoted text -
>
> - Show quoted text -
So, assuming that my speedometer is correct, running approximately
2500 rpms in 5th gear at 65 mph will NOT hurt my engine or cause
increased engine wear? If I were to shift into OD (6th), what is the
approximate rpms that I should be running so as to not cause lugging
or increased engine wear?
THANKS
> Tracie wrote:
> > Hello all. I have a 2006 Wrangler X with 6 speed manual tranny, 3.07
> > gearing, and D30 front/35 rear. I recently upgraded my tires from the
> > stock 215/75/15 to 31/10.5/15 BFG All Terrain T/A KO. I am looking
> > for a reliable way to tell if my speedometer is off at all with the
> > tire upgrade. I do not have access to a GPS system. What I HAVE done
> > is to use the tripometer (with tenths), and hold steady at 60 mph (my
> > speedometer said 60) for one mile while watching my clock. I am
> > EXTREMELY close to going 1 mile in 1 minute by using this method. Is
> > this reliable to tell whether or not my speedometer is dead on? I
> > have NOT changed the speedometer gear yet, or had the computer changed
> > to reflect the larger sized tires. Also, I am not using my OD (6th)
> > much on the highway, but when I get up to 65 (the speedometer says
> > 65), I am running at about 2500 rpms in 5th. Is this bad, or should I
> > be shifting into the OD (6th)? I do fine with 1st through 5th. Just
> > not sure what speed or what rpms I should be using 6th. Any help is
> > really appreciated.
>
> The (ones that have posed here) older TJ speedometers became correct
> when 31" tire were put on.
>
> Your mile per minute is a good base to tell it is close.
>
> The only other way is to find a measured mile or a friend with a GPS or
> even ask a cop to pace you because 'you just got new tires and don't
> want to break the law'. Only a cop's speedometer would be reliable for
> this, cars can be off too according to tire size.
>
> I find 'my' engine 'much' prefers to be running at 2300-2500 rpm on the
> highway which I get with my 4th gear. (have 33's and 3.31 gears) That
> rpm gives me good throttle control and prevents engine lugging. I also
> get a pretty stable 11L/100km or 23 mpg running there.
>
> If I go to overdrive or 5th gear, the rpm drops to 1750 or so at 65 mph
> which makes for the need of the full gas pedal travel to adjust speed or
> hold a hill or wind vs a twitch of the pedal in 4th. This low rpm drops
> my gas mileage by at least 5-8 mpg.
>
> You can find out easy. Just compare gas mileages when using only 5th on
> the highway and when using 6th mostly. I have one trip I do lots to get
> bush camping which is 201 km from gas station to gas station so I have
> an easy check point.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> Canadian Off Road Trips Photos: Non members can still view!
> Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
> (More Off Road album links at bottom of the view page)- Hide quoted text -
>
> - Show quoted text -
So, assuming that my speedometer is correct, running approximately
2500 rpms in 5th gear at 65 mph will NOT hurt my engine or cause
increased engine wear? If I were to shift into OD (6th), what is the
approximate rpms that I should be running so as to not cause lugging
or increased engine wear?
THANKS
09-17-2007, 11:26 AM
#23
Guest
Posts: n/a
Re: ACCURATE SPEEDOMETER?
On Sep 17, 11:17 am, Mike Romain <roma...@sympatico.ca> wrote:
> Tracie wrote:
> > Hello all. I have a 2006 Wrangler X with 6 speed manual tranny, 3.07
> > gearing, and D30 front/35 rear. I recently upgraded my tires from the
> > stock 215/75/15 to 31/10.5/15 BFG All Terrain T/A KO. I am looking
> > for a reliable way to tell if my speedometer is off at all with the
> > tire upgrade. I do not have access to a GPS system. What I HAVE done
> > is to use the tripometer (with tenths), and hold steady at 60 mph (my
> > speedometer said 60) for one mile while watching my clock. I am
> > EXTREMELY close to going 1 mile in 1 minute by using this method. Is
> > this reliable to tell whether or not my speedometer is dead on? I
> > have NOT changed the speedometer gear yet, or had the computer changed
> > to reflect the larger sized tires. Also, I am not using my OD (6th)
> > much on the highway, but when I get up to 65 (the speedometer says
> > 65), I am running at about 2500 rpms in 5th. Is this bad, or should I
> > be shifting into the OD (6th)? I do fine with 1st through 5th. Just
> > not sure what speed or what rpms I should be using 6th. Any help is
> > really appreciated.
>
> The (ones that have posed here) older TJ speedometers became correct
> when 31" tire were put on.
>
> Your mile per minute is a good base to tell it is close.
>
> The only other way is to find a measured mile or a friend with a GPS or
> even ask a cop to pace you because 'you just got new tires and don't
> want to break the law'. Only a cop's speedometer would be reliable for
> this, cars can be off too according to tire size.
>
> I find 'my' engine 'much' prefers to be running at 2300-2500 rpm on the
> highway which I get with my 4th gear. (have 33's and 3.31 gears) That
> rpm gives me good throttle control and prevents engine lugging. I also
> get a pretty stable 11L/100km or 23 mpg running there.
>
> If I go to overdrive or 5th gear, the rpm drops to 1750 or so at 65 mph
> which makes for the need of the full gas pedal travel to adjust speed or
> hold a hill or wind vs a twitch of the pedal in 4th. This low rpm drops
> my gas mileage by at least 5-8 mpg.
>
> You can find out easy. Just compare gas mileages when using only 5th on
> the highway and when using 6th mostly. I have one trip I do lots to get
> bush camping which is 201 km from gas station to gas station so I have
> an easy check point.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> Canadian Off Road Trips Photos: Non members can still view!
> Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
> (More Off Road album links at bottom of the view page)- Hide quoted text -
>
> - Show quoted text -
So, assuming that my speedometer is correct, running approximately
2500 rpms in 5th gear at 65 mph will NOT hurt my engine or cause
increased engine wear? If I were to shift into OD (6th), what is the
approximate rpms that I should be running so as to not cause lugging
or increased engine wear?
THANKS
> Tracie wrote:
> > Hello all. I have a 2006 Wrangler X with 6 speed manual tranny, 3.07
> > gearing, and D30 front/35 rear. I recently upgraded my tires from the
> > stock 215/75/15 to 31/10.5/15 BFG All Terrain T/A KO. I am looking
> > for a reliable way to tell if my speedometer is off at all with the
> > tire upgrade. I do not have access to a GPS system. What I HAVE done
> > is to use the tripometer (with tenths), and hold steady at 60 mph (my
> > speedometer said 60) for one mile while watching my clock. I am
> > EXTREMELY close to going 1 mile in 1 minute by using this method. Is
> > this reliable to tell whether or not my speedometer is dead on? I
> > have NOT changed the speedometer gear yet, or had the computer changed
> > to reflect the larger sized tires. Also, I am not using my OD (6th)
> > much on the highway, but when I get up to 65 (the speedometer says
> > 65), I am running at about 2500 rpms in 5th. Is this bad, or should I
> > be shifting into the OD (6th)? I do fine with 1st through 5th. Just
> > not sure what speed or what rpms I should be using 6th. Any help is
> > really appreciated.
>
> The (ones that have posed here) older TJ speedometers became correct
> when 31" tire were put on.
>
> Your mile per minute is a good base to tell it is close.
>
> The only other way is to find a measured mile or a friend with a GPS or
> even ask a cop to pace you because 'you just got new tires and don't
> want to break the law'. Only a cop's speedometer would be reliable for
> this, cars can be off too according to tire size.
>
> I find 'my' engine 'much' prefers to be running at 2300-2500 rpm on the
> highway which I get with my 4th gear. (have 33's and 3.31 gears) That
> rpm gives me good throttle control and prevents engine lugging. I also
> get a pretty stable 11L/100km or 23 mpg running there.
>
> If I go to overdrive or 5th gear, the rpm drops to 1750 or so at 65 mph
> which makes for the need of the full gas pedal travel to adjust speed or
> hold a hill or wind vs a twitch of the pedal in 4th. This low rpm drops
> my gas mileage by at least 5-8 mpg.
>
> You can find out easy. Just compare gas mileages when using only 5th on
> the highway and when using 6th mostly. I have one trip I do lots to get
> bush camping which is 201 km from gas station to gas station so I have
> an easy check point.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> Canadian Off Road Trips Photos: Non members can still view!
> Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
> (More Off Road album links at bottom of the view page)- Hide quoted text -
>
> - Show quoted text -
So, assuming that my speedometer is correct, running approximately
2500 rpms in 5th gear at 65 mph will NOT hurt my engine or cause
increased engine wear? If I were to shift into OD (6th), what is the
approximate rpms that I should be running so as to not cause lugging
or increased engine wear?
THANKS
09-17-2007, 11:26 AM
#24
Guest
Posts: n/a
Re: ACCURATE SPEEDOMETER?
On Sep 17, 11:17 am, Mike Romain <roma...@sympatico.ca> wrote:
> Tracie wrote:
> > Hello all. I have a 2006 Wrangler X with 6 speed manual tranny, 3.07
> > gearing, and D30 front/35 rear. I recently upgraded my tires from the
> > stock 215/75/15 to 31/10.5/15 BFG All Terrain T/A KO. I am looking
> > for a reliable way to tell if my speedometer is off at all with the
> > tire upgrade. I do not have access to a GPS system. What I HAVE done
> > is to use the tripometer (with tenths), and hold steady at 60 mph (my
> > speedometer said 60) for one mile while watching my clock. I am
> > EXTREMELY close to going 1 mile in 1 minute by using this method. Is
> > this reliable to tell whether or not my speedometer is dead on? I
> > have NOT changed the speedometer gear yet, or had the computer changed
> > to reflect the larger sized tires. Also, I am not using my OD (6th)
> > much on the highway, but when I get up to 65 (the speedometer says
> > 65), I am running at about 2500 rpms in 5th. Is this bad, or should I
> > be shifting into the OD (6th)? I do fine with 1st through 5th. Just
> > not sure what speed or what rpms I should be using 6th. Any help is
> > really appreciated.
>
> The (ones that have posed here) older TJ speedometers became correct
> when 31" tire were put on.
>
> Your mile per minute is a good base to tell it is close.
>
> The only other way is to find a measured mile or a friend with a GPS or
> even ask a cop to pace you because 'you just got new tires and don't
> want to break the law'. Only a cop's speedometer would be reliable for
> this, cars can be off too according to tire size.
>
> I find 'my' engine 'much' prefers to be running at 2300-2500 rpm on the
> highway which I get with my 4th gear. (have 33's and 3.31 gears) That
> rpm gives me good throttle control and prevents engine lugging. I also
> get a pretty stable 11L/100km or 23 mpg running there.
>
> If I go to overdrive or 5th gear, the rpm drops to 1750 or so at 65 mph
> which makes for the need of the full gas pedal travel to adjust speed or
> hold a hill or wind vs a twitch of the pedal in 4th. This low rpm drops
> my gas mileage by at least 5-8 mpg.
>
> You can find out easy. Just compare gas mileages when using only 5th on
> the highway and when using 6th mostly. I have one trip I do lots to get
> bush camping which is 201 km from gas station to gas station so I have
> an easy check point.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> Canadian Off Road Trips Photos: Non members can still view!
> Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
> (More Off Road album links at bottom of the view page)- Hide quoted text -
>
> - Show quoted text -
So, assuming that my speedometer is correct, running approximately
2500 rpms in 5th gear at 65 mph will NOT hurt my engine or cause
increased engine wear? If I were to shift into OD (6th), what is the
approximate rpms that I should be running so as to not cause lugging
or increased engine wear?
THANKS
> Tracie wrote:
> > Hello all. I have a 2006 Wrangler X with 6 speed manual tranny, 3.07
> > gearing, and D30 front/35 rear. I recently upgraded my tires from the
> > stock 215/75/15 to 31/10.5/15 BFG All Terrain T/A KO. I am looking
> > for a reliable way to tell if my speedometer is off at all with the
> > tire upgrade. I do not have access to a GPS system. What I HAVE done
> > is to use the tripometer (with tenths), and hold steady at 60 mph (my
> > speedometer said 60) for one mile while watching my clock. I am
> > EXTREMELY close to going 1 mile in 1 minute by using this method. Is
> > this reliable to tell whether or not my speedometer is dead on? I
> > have NOT changed the speedometer gear yet, or had the computer changed
> > to reflect the larger sized tires. Also, I am not using my OD (6th)
> > much on the highway, but when I get up to 65 (the speedometer says
> > 65), I am running at about 2500 rpms in 5th. Is this bad, or should I
> > be shifting into the OD (6th)? I do fine with 1st through 5th. Just
> > not sure what speed or what rpms I should be using 6th. Any help is
> > really appreciated.
>
> The (ones that have posed here) older TJ speedometers became correct
> when 31" tire were put on.
>
> Your mile per minute is a good base to tell it is close.
>
> The only other way is to find a measured mile or a friend with a GPS or
> even ask a cop to pace you because 'you just got new tires and don't
> want to break the law'. Only a cop's speedometer would be reliable for
> this, cars can be off too according to tire size.
>
> I find 'my' engine 'much' prefers to be running at 2300-2500 rpm on the
> highway which I get with my 4th gear. (have 33's and 3.31 gears) That
> rpm gives me good throttle control and prevents engine lugging. I also
> get a pretty stable 11L/100km or 23 mpg running there.
>
> If I go to overdrive or 5th gear, the rpm drops to 1750 or so at 65 mph
> which makes for the need of the full gas pedal travel to adjust speed or
> hold a hill or wind vs a twitch of the pedal in 4th. This low rpm drops
> my gas mileage by at least 5-8 mpg.
>
> You can find out easy. Just compare gas mileages when using only 5th on
> the highway and when using 6th mostly. I have one trip I do lots to get
> bush camping which is 201 km from gas station to gas station so I have
> an easy check point.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> Canadian Off Road Trips Photos: Non members can still view!
> Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
> (More Off Road album links at bottom of the view page)- Hide quoted text -
>
> - Show quoted text -
So, assuming that my speedometer is correct, running approximately
2500 rpms in 5th gear at 65 mph will NOT hurt my engine or cause
increased engine wear? If I were to shift into OD (6th), what is the
approximate rpms that I should be running so as to not cause lugging
or increased engine wear?
THANKS
09-17-2007, 11:26 AM
#25
Guest
Posts: n/a
Re: ACCURATE SPEEDOMETER?
On Sep 17, 11:17 am, Mike Romain <roma...@sympatico.ca> wrote:
> Tracie wrote:
> > Hello all. I have a 2006 Wrangler X with 6 speed manual tranny, 3.07
> > gearing, and D30 front/35 rear. I recently upgraded my tires from the
> > stock 215/75/15 to 31/10.5/15 BFG All Terrain T/A KO. I am looking
> > for a reliable way to tell if my speedometer is off at all with the
> > tire upgrade. I do not have access to a GPS system. What I HAVE done
> > is to use the tripometer (with tenths), and hold steady at 60 mph (my
> > speedometer said 60) for one mile while watching my clock. I am
> > EXTREMELY close to going 1 mile in 1 minute by using this method. Is
> > this reliable to tell whether or not my speedometer is dead on? I
> > have NOT changed the speedometer gear yet, or had the computer changed
> > to reflect the larger sized tires. Also, I am not using my OD (6th)
> > much on the highway, but when I get up to 65 (the speedometer says
> > 65), I am running at about 2500 rpms in 5th. Is this bad, or should I
> > be shifting into the OD (6th)? I do fine with 1st through 5th. Just
> > not sure what speed or what rpms I should be using 6th. Any help is
> > really appreciated.
>
> The (ones that have posed here) older TJ speedometers became correct
> when 31" tire were put on.
>
> Your mile per minute is a good base to tell it is close.
>
> The only other way is to find a measured mile or a friend with a GPS or
> even ask a cop to pace you because 'you just got new tires and don't
> want to break the law'. Only a cop's speedometer would be reliable for
> this, cars can be off too according to tire size.
>
> I find 'my' engine 'much' prefers to be running at 2300-2500 rpm on the
> highway which I get with my 4th gear. (have 33's and 3.31 gears) That
> rpm gives me good throttle control and prevents engine lugging. I also
> get a pretty stable 11L/100km or 23 mpg running there.
>
> If I go to overdrive or 5th gear, the rpm drops to 1750 or so at 65 mph
> which makes for the need of the full gas pedal travel to adjust speed or
> hold a hill or wind vs a twitch of the pedal in 4th. This low rpm drops
> my gas mileage by at least 5-8 mpg.
>
> You can find out easy. Just compare gas mileages when using only 5th on
> the highway and when using 6th mostly. I have one trip I do lots to get
> bush camping which is 201 km from gas station to gas station so I have
> an easy check point.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> Canadian Off Road Trips Photos: Non members can still view!
> Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
> (More Off Road album links at bottom of the view page)- Hide quoted text -
>
> - Show quoted text -
So, assuming that my speedometer is correct, running approximately
2500 rpms in 5th gear at 65 mph will NOT hurt my engine or cause
increased engine wear? If I were to shift into OD (6th), what is the
approximate rpms that I should be running so as to not cause lugging
or increased engine wear?
THANKS
> Tracie wrote:
> > Hello all. I have a 2006 Wrangler X with 6 speed manual tranny, 3.07
> > gearing, and D30 front/35 rear. I recently upgraded my tires from the
> > stock 215/75/15 to 31/10.5/15 BFG All Terrain T/A KO. I am looking
> > for a reliable way to tell if my speedometer is off at all with the
> > tire upgrade. I do not have access to a GPS system. What I HAVE done
> > is to use the tripometer (with tenths), and hold steady at 60 mph (my
> > speedometer said 60) for one mile while watching my clock. I am
> > EXTREMELY close to going 1 mile in 1 minute by using this method. Is
> > this reliable to tell whether or not my speedometer is dead on? I
> > have NOT changed the speedometer gear yet, or had the computer changed
> > to reflect the larger sized tires. Also, I am not using my OD (6th)
> > much on the highway, but when I get up to 65 (the speedometer says
> > 65), I am running at about 2500 rpms in 5th. Is this bad, or should I
> > be shifting into the OD (6th)? I do fine with 1st through 5th. Just
> > not sure what speed or what rpms I should be using 6th. Any help is
> > really appreciated.
>
> The (ones that have posed here) older TJ speedometers became correct
> when 31" tire were put on.
>
> Your mile per minute is a good base to tell it is close.
>
> The only other way is to find a measured mile or a friend with a GPS or
> even ask a cop to pace you because 'you just got new tires and don't
> want to break the law'. Only a cop's speedometer would be reliable for
> this, cars can be off too according to tire size.
>
> I find 'my' engine 'much' prefers to be running at 2300-2500 rpm on the
> highway which I get with my 4th gear. (have 33's and 3.31 gears) That
> rpm gives me good throttle control and prevents engine lugging. I also
> get a pretty stable 11L/100km or 23 mpg running there.
>
> If I go to overdrive or 5th gear, the rpm drops to 1750 or so at 65 mph
> which makes for the need of the full gas pedal travel to adjust speed or
> hold a hill or wind vs a twitch of the pedal in 4th. This low rpm drops
> my gas mileage by at least 5-8 mpg.
>
> You can find out easy. Just compare gas mileages when using only 5th on
> the highway and when using 6th mostly. I have one trip I do lots to get
> bush camping which is 201 km from gas station to gas station so I have
> an easy check point.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> Canadian Off Road Trips Photos: Non members can still view!
> Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
> (More Off Road album links at bottom of the view page)- Hide quoted text -
>
> - Show quoted text -
So, assuming that my speedometer is correct, running approximately
2500 rpms in 5th gear at 65 mph will NOT hurt my engine or cause
increased engine wear? If I were to shift into OD (6th), what is the
approximate rpms that I should be running so as to not cause lugging
or increased engine wear?
THANKS
09-17-2007, 11:34 AM
#26
Guest
Posts: n/a
Re: ACCURATE SPEEDOMETER?
On Sep 17, 11:26 am, Tracie <brain...@upstate.edu> wrote:
> On Sep 17, 11:17 am, Mike Romain <roma...@sympatico.ca> wrote:
>
>
>
>
>
> > Tracie wrote:
> > > Hello all. I have a 2006 Wrangler X with 6 speed manual tranny, 3.07
> > > gearing, and D30 front/35 rear. I recently upgraded my tires from the
> > > stock 215/75/15 to 31/10.5/15 BFG All Terrain T/A KO. I am looking
> > > for a reliable way to tell if my speedometer is off at all with the
> > > tire upgrade. I do not have access to a GPS system. What I HAVE done
> > > is to use the tripometer (with tenths), and hold steady at 60 mph (my
> > > speedometer said 60) for one mile while watching my clock. I am
> > > EXTREMELY close to going 1 mile in 1 minute by using this method. Is
> > > this reliable to tell whether or not my speedometer is dead on? I
> > > have NOT changed the speedometer gear yet, or had the computer changed
> > > to reflect the larger sized tires. Also, I am not using my OD (6th)
> > > much on the highway, but when I get up to 65 (the speedometer says
> > > 65), I am running at about 2500 rpms in 5th. Is this bad, or should I
> > > be shifting into the OD (6th)? I do fine with 1st through 5th. Just
> > > not sure what speed or what rpms I should be using 6th. Any help is
> > > really appreciated.
>
> > The (ones that have posed here) older TJ speedometers became correct
> > when 31" tire were put on.
>
> > Your mile per minute is a good base to tell it is close.
>
> > The only other way is to find a measured mile or a friend with a GPS or
> > even ask a cop to pace you because 'you just got new tires and don't
> > want to break the law'. Only a cop's speedometer would be reliable for
> > this, cars can be off too according to tire size.
>
> > I find 'my' engine 'much' prefers to be running at 2300-2500 rpm on the
> > highway which I get with my 4th gear. (have 33's and 3.31 gears) That
> > rpm gives me good throttle control and prevents engine lugging. I also
> > get a pretty stable 11L/100km or 23 mpg running there.
>
> > If I go to overdrive or 5th gear, the rpm drops to 1750 or so at 65 mph
> > which makes for the need of the full gas pedal travel to adjust speed or
> > hold a hill or wind vs a twitch of the pedal in 4th. This low rpm drops
> > my gas mileage by at least 5-8 mpg.
>
> > You can find out easy. Just compare gas mileages when using only 5th on
> > the highway and when using 6th mostly. I have one trip I do lots to get
> > bush camping which is 201 km from gas station to gas station so I have
> > an easy check point.
>
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> > Canadian Off Road Trips Photos: Non members can still view!
> > Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
> > (More Off Road album links at bottom of the view page)- Hide quoted text -
>
> > - Show quoted text -
>
> So, assuming that my speedometer is correct, running approximately
> 2500 rpms in 5th gear at 65 mph will NOT hurt my engine or cause
> increased engine wear? If I were to shift into OD (6th), what is the
> approximate rpms that I should be running so as to not cause lugging
> or increased engine wear?
>
> THANKS- Hide quoted text -
>
> - Show quoted text -
Oh, nevermind. I think I just answered my own question. : D
I am assuming that the approximate 2500 rpms would apply to the OD
(6th) gear as well to prevent increased engine wear and lugging?
> On Sep 17, 11:17 am, Mike Romain <roma...@sympatico.ca> wrote:
>
>
>
>
>
> > Tracie wrote:
> > > Hello all. I have a 2006 Wrangler X with 6 speed manual tranny, 3.07
> > > gearing, and D30 front/35 rear. I recently upgraded my tires from the
> > > stock 215/75/15 to 31/10.5/15 BFG All Terrain T/A KO. I am looking
> > > for a reliable way to tell if my speedometer is off at all with the
> > > tire upgrade. I do not have access to a GPS system. What I HAVE done
> > > is to use the tripometer (with tenths), and hold steady at 60 mph (my
> > > speedometer said 60) for one mile while watching my clock. I am
> > > EXTREMELY close to going 1 mile in 1 minute by using this method. Is
> > > this reliable to tell whether or not my speedometer is dead on? I
> > > have NOT changed the speedometer gear yet, or had the computer changed
> > > to reflect the larger sized tires. Also, I am not using my OD (6th)
> > > much on the highway, but when I get up to 65 (the speedometer says
> > > 65), I am running at about 2500 rpms in 5th. Is this bad, or should I
> > > be shifting into the OD (6th)? I do fine with 1st through 5th. Just
> > > not sure what speed or what rpms I should be using 6th. Any help is
> > > really appreciated.
>
> > The (ones that have posed here) older TJ speedometers became correct
> > when 31" tire were put on.
>
> > Your mile per minute is a good base to tell it is close.
>
> > The only other way is to find a measured mile or a friend with a GPS or
> > even ask a cop to pace you because 'you just got new tires and don't
> > want to break the law'. Only a cop's speedometer would be reliable for
> > this, cars can be off too according to tire size.
>
> > I find 'my' engine 'much' prefers to be running at 2300-2500 rpm on the
> > highway which I get with my 4th gear. (have 33's and 3.31 gears) That
> > rpm gives me good throttle control and prevents engine lugging. I also
> > get a pretty stable 11L/100km or 23 mpg running there.
>
> > If I go to overdrive or 5th gear, the rpm drops to 1750 or so at 65 mph
> > which makes for the need of the full gas pedal travel to adjust speed or
> > hold a hill or wind vs a twitch of the pedal in 4th. This low rpm drops
> > my gas mileage by at least 5-8 mpg.
>
> > You can find out easy. Just compare gas mileages when using only 5th on
> > the highway and when using 6th mostly. I have one trip I do lots to get
> > bush camping which is 201 km from gas station to gas station so I have
> > an easy check point.
>
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> > Canadian Off Road Trips Photos: Non members can still view!
> > Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
> > (More Off Road album links at bottom of the view page)- Hide quoted text -
>
> > - Show quoted text -
>
> So, assuming that my speedometer is correct, running approximately
> 2500 rpms in 5th gear at 65 mph will NOT hurt my engine or cause
> increased engine wear? If I were to shift into OD (6th), what is the
> approximate rpms that I should be running so as to not cause lugging
> or increased engine wear?
>
> THANKS- Hide quoted text -
>
> - Show quoted text -
Oh, nevermind. I think I just answered my own question. : D
I am assuming that the approximate 2500 rpms would apply to the OD
(6th) gear as well to prevent increased engine wear and lugging?
09-17-2007, 11:34 AM
#27
Guest
Posts: n/a
Re: ACCURATE SPEEDOMETER?
On Sep 17, 11:26 am, Tracie <brain...@upstate.edu> wrote:
> On Sep 17, 11:17 am, Mike Romain <roma...@sympatico.ca> wrote:
>
>
>
>
>
> > Tracie wrote:
> > > Hello all. I have a 2006 Wrangler X with 6 speed manual tranny, 3.07
> > > gearing, and D30 front/35 rear. I recently upgraded my tires from the
> > > stock 215/75/15 to 31/10.5/15 BFG All Terrain T/A KO. I am looking
> > > for a reliable way to tell if my speedometer is off at all with the
> > > tire upgrade. I do not have access to a GPS system. What I HAVE done
> > > is to use the tripometer (with tenths), and hold steady at 60 mph (my
> > > speedometer said 60) for one mile while watching my clock. I am
> > > EXTREMELY close to going 1 mile in 1 minute by using this method. Is
> > > this reliable to tell whether or not my speedometer is dead on? I
> > > have NOT changed the speedometer gear yet, or had the computer changed
> > > to reflect the larger sized tires. Also, I am not using my OD (6th)
> > > much on the highway, but when I get up to 65 (the speedometer says
> > > 65), I am running at about 2500 rpms in 5th. Is this bad, or should I
> > > be shifting into the OD (6th)? I do fine with 1st through 5th. Just
> > > not sure what speed or what rpms I should be using 6th. Any help is
> > > really appreciated.
>
> > The (ones that have posed here) older TJ speedometers became correct
> > when 31" tire were put on.
>
> > Your mile per minute is a good base to tell it is close.
>
> > The only other way is to find a measured mile or a friend with a GPS or
> > even ask a cop to pace you because 'you just got new tires and don't
> > want to break the law'. Only a cop's speedometer would be reliable for
> > this, cars can be off too according to tire size.
>
> > I find 'my' engine 'much' prefers to be running at 2300-2500 rpm on the
> > highway which I get with my 4th gear. (have 33's and 3.31 gears) That
> > rpm gives me good throttle control and prevents engine lugging. I also
> > get a pretty stable 11L/100km or 23 mpg running there.
>
> > If I go to overdrive or 5th gear, the rpm drops to 1750 or so at 65 mph
> > which makes for the need of the full gas pedal travel to adjust speed or
> > hold a hill or wind vs a twitch of the pedal in 4th. This low rpm drops
> > my gas mileage by at least 5-8 mpg.
>
> > You can find out easy. Just compare gas mileages when using only 5th on
> > the highway and when using 6th mostly. I have one trip I do lots to get
> > bush camping which is 201 km from gas station to gas station so I have
> > an easy check point.
>
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> > Canadian Off Road Trips Photos: Non members can still view!
> > Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
> > (More Off Road album links at bottom of the view page)- Hide quoted text -
>
> > - Show quoted text -
>
> So, assuming that my speedometer is correct, running approximately
> 2500 rpms in 5th gear at 65 mph will NOT hurt my engine or cause
> increased engine wear? If I were to shift into OD (6th), what is the
> approximate rpms that I should be running so as to not cause lugging
> or increased engine wear?
>
> THANKS- Hide quoted text -
>
> - Show quoted text -
Oh, nevermind. I think I just answered my own question. : D
I am assuming that the approximate 2500 rpms would apply to the OD
(6th) gear as well to prevent increased engine wear and lugging?
> On Sep 17, 11:17 am, Mike Romain <roma...@sympatico.ca> wrote:
>
>
>
>
>
> > Tracie wrote:
> > > Hello all. I have a 2006 Wrangler X with 6 speed manual tranny, 3.07
> > > gearing, and D30 front/35 rear. I recently upgraded my tires from the
> > > stock 215/75/15 to 31/10.5/15 BFG All Terrain T/A KO. I am looking
> > > for a reliable way to tell if my speedometer is off at all with the
> > > tire upgrade. I do not have access to a GPS system. What I HAVE done
> > > is to use the tripometer (with tenths), and hold steady at 60 mph (my
> > > speedometer said 60) for one mile while watching my clock. I am
> > > EXTREMELY close to going 1 mile in 1 minute by using this method. Is
> > > this reliable to tell whether or not my speedometer is dead on? I
> > > have NOT changed the speedometer gear yet, or had the computer changed
> > > to reflect the larger sized tires. Also, I am not using my OD (6th)
> > > much on the highway, but when I get up to 65 (the speedometer says
> > > 65), I am running at about 2500 rpms in 5th. Is this bad, or should I
> > > be shifting into the OD (6th)? I do fine with 1st through 5th. Just
> > > not sure what speed or what rpms I should be using 6th. Any help is
> > > really appreciated.
>
> > The (ones that have posed here) older TJ speedometers became correct
> > when 31" tire were put on.
>
> > Your mile per minute is a good base to tell it is close.
>
> > The only other way is to find a measured mile or a friend with a GPS or
> > even ask a cop to pace you because 'you just got new tires and don't
> > want to break the law'. Only a cop's speedometer would be reliable for
> > this, cars can be off too according to tire size.
>
> > I find 'my' engine 'much' prefers to be running at 2300-2500 rpm on the
> > highway which I get with my 4th gear. (have 33's and 3.31 gears) That
> > rpm gives me good throttle control and prevents engine lugging. I also
> > get a pretty stable 11L/100km or 23 mpg running there.
>
> > If I go to overdrive or 5th gear, the rpm drops to 1750 or so at 65 mph
> > which makes for the need of the full gas pedal travel to adjust speed or
> > hold a hill or wind vs a twitch of the pedal in 4th. This low rpm drops
> > my gas mileage by at least 5-8 mpg.
>
> > You can find out easy. Just compare gas mileages when using only 5th on
> > the highway and when using 6th mostly. I have one trip I do lots to get
> > bush camping which is 201 km from gas station to gas station so I have
> > an easy check point.
>
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> > Canadian Off Road Trips Photos: Non members can still view!
> > Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
> > (More Off Road album links at bottom of the view page)- Hide quoted text -
>
> > - Show quoted text -
>
> So, assuming that my speedometer is correct, running approximately
> 2500 rpms in 5th gear at 65 mph will NOT hurt my engine or cause
> increased engine wear? If I were to shift into OD (6th), what is the
> approximate rpms that I should be running so as to not cause lugging
> or increased engine wear?
>
> THANKS- Hide quoted text -
>
> - Show quoted text -
Oh, nevermind. I think I just answered my own question. : D
I am assuming that the approximate 2500 rpms would apply to the OD
(6th) gear as well to prevent increased engine wear and lugging?
09-17-2007, 11:34 AM
#28
Guest
Posts: n/a
Re: ACCURATE SPEEDOMETER?
On Sep 17, 11:26 am, Tracie <brain...@upstate.edu> wrote:
> On Sep 17, 11:17 am, Mike Romain <roma...@sympatico.ca> wrote:
>
>
>
>
>
> > Tracie wrote:
> > > Hello all. I have a 2006 Wrangler X with 6 speed manual tranny, 3.07
> > > gearing, and D30 front/35 rear. I recently upgraded my tires from the
> > > stock 215/75/15 to 31/10.5/15 BFG All Terrain T/A KO. I am looking
> > > for a reliable way to tell if my speedometer is off at all with the
> > > tire upgrade. I do not have access to a GPS system. What I HAVE done
> > > is to use the tripometer (with tenths), and hold steady at 60 mph (my
> > > speedometer said 60) for one mile while watching my clock. I am
> > > EXTREMELY close to going 1 mile in 1 minute by using this method. Is
> > > this reliable to tell whether or not my speedometer is dead on? I
> > > have NOT changed the speedometer gear yet, or had the computer changed
> > > to reflect the larger sized tires. Also, I am not using my OD (6th)
> > > much on the highway, but when I get up to 65 (the speedometer says
> > > 65), I am running at about 2500 rpms in 5th. Is this bad, or should I
> > > be shifting into the OD (6th)? I do fine with 1st through 5th. Just
> > > not sure what speed or what rpms I should be using 6th. Any help is
> > > really appreciated.
>
> > The (ones that have posed here) older TJ speedometers became correct
> > when 31" tire were put on.
>
> > Your mile per minute is a good base to tell it is close.
>
> > The only other way is to find a measured mile or a friend with a GPS or
> > even ask a cop to pace you because 'you just got new tires and don't
> > want to break the law'. Only a cop's speedometer would be reliable for
> > this, cars can be off too according to tire size.
>
> > I find 'my' engine 'much' prefers to be running at 2300-2500 rpm on the
> > highway which I get with my 4th gear. (have 33's and 3.31 gears) That
> > rpm gives me good throttle control and prevents engine lugging. I also
> > get a pretty stable 11L/100km or 23 mpg running there.
>
> > If I go to overdrive or 5th gear, the rpm drops to 1750 or so at 65 mph
> > which makes for the need of the full gas pedal travel to adjust speed or
> > hold a hill or wind vs a twitch of the pedal in 4th. This low rpm drops
> > my gas mileage by at least 5-8 mpg.
>
> > You can find out easy. Just compare gas mileages when using only 5th on
> > the highway and when using 6th mostly. I have one trip I do lots to get
> > bush camping which is 201 km from gas station to gas station so I have
> > an easy check point.
>
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> > Canadian Off Road Trips Photos: Non members can still view!
> > Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
> > (More Off Road album links at bottom of the view page)- Hide quoted text -
>
> > - Show quoted text -
>
> So, assuming that my speedometer is correct, running approximately
> 2500 rpms in 5th gear at 65 mph will NOT hurt my engine or cause
> increased engine wear? If I were to shift into OD (6th), what is the
> approximate rpms that I should be running so as to not cause lugging
> or increased engine wear?
>
> THANKS- Hide quoted text -
>
> - Show quoted text -
Oh, nevermind. I think I just answered my own question. : D
I am assuming that the approximate 2500 rpms would apply to the OD
(6th) gear as well to prevent increased engine wear and lugging?
> On Sep 17, 11:17 am, Mike Romain <roma...@sympatico.ca> wrote:
>
>
>
>
>
> > Tracie wrote:
> > > Hello all. I have a 2006 Wrangler X with 6 speed manual tranny, 3.07
> > > gearing, and D30 front/35 rear. I recently upgraded my tires from the
> > > stock 215/75/15 to 31/10.5/15 BFG All Terrain T/A KO. I am looking
> > > for a reliable way to tell if my speedometer is off at all with the
> > > tire upgrade. I do not have access to a GPS system. What I HAVE done
> > > is to use the tripometer (with tenths), and hold steady at 60 mph (my
> > > speedometer said 60) for one mile while watching my clock. I am
> > > EXTREMELY close to going 1 mile in 1 minute by using this method. Is
> > > this reliable to tell whether or not my speedometer is dead on? I
> > > have NOT changed the speedometer gear yet, or had the computer changed
> > > to reflect the larger sized tires. Also, I am not using my OD (6th)
> > > much on the highway, but when I get up to 65 (the speedometer says
> > > 65), I am running at about 2500 rpms in 5th. Is this bad, or should I
> > > be shifting into the OD (6th)? I do fine with 1st through 5th. Just
> > > not sure what speed or what rpms I should be using 6th. Any help is
> > > really appreciated.
>
> > The (ones that have posed here) older TJ speedometers became correct
> > when 31" tire were put on.
>
> > Your mile per minute is a good base to tell it is close.
>
> > The only other way is to find a measured mile or a friend with a GPS or
> > even ask a cop to pace you because 'you just got new tires and don't
> > want to break the law'. Only a cop's speedometer would be reliable for
> > this, cars can be off too according to tire size.
>
> > I find 'my' engine 'much' prefers to be running at 2300-2500 rpm on the
> > highway which I get with my 4th gear. (have 33's and 3.31 gears) That
> > rpm gives me good throttle control and prevents engine lugging. I also
> > get a pretty stable 11L/100km or 23 mpg running there.
>
> > If I go to overdrive or 5th gear, the rpm drops to 1750 or so at 65 mph
> > which makes for the need of the full gas pedal travel to adjust speed or
> > hold a hill or wind vs a twitch of the pedal in 4th. This low rpm drops
> > my gas mileage by at least 5-8 mpg.
>
> > You can find out easy. Just compare gas mileages when using only 5th on
> > the highway and when using 6th mostly. I have one trip I do lots to get
> > bush camping which is 201 km from gas station to gas station so I have
> > an easy check point.
>
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> > Canadian Off Road Trips Photos: Non members can still view!
> > Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
> > (More Off Road album links at bottom of the view page)- Hide quoted text -
>
> > - Show quoted text -
>
> So, assuming that my speedometer is correct, running approximately
> 2500 rpms in 5th gear at 65 mph will NOT hurt my engine or cause
> increased engine wear? If I were to shift into OD (6th), what is the
> approximate rpms that I should be running so as to not cause lugging
> or increased engine wear?
>
> THANKS- Hide quoted text -
>
> - Show quoted text -
Oh, nevermind. I think I just answered my own question. : D
I am assuming that the approximate 2500 rpms would apply to the OD
(6th) gear as well to prevent increased engine wear and lugging?
09-17-2007, 11:34 AM
#29
Guest
Posts: n/a
Re: ACCURATE SPEEDOMETER?
On Sep 17, 11:26 am, Tracie <brain...@upstate.edu> wrote:
> On Sep 17, 11:17 am, Mike Romain <roma...@sympatico.ca> wrote:
>
>
>
>
>
> > Tracie wrote:
> > > Hello all. I have a 2006 Wrangler X with 6 speed manual tranny, 3.07
> > > gearing, and D30 front/35 rear. I recently upgraded my tires from the
> > > stock 215/75/15 to 31/10.5/15 BFG All Terrain T/A KO. I am looking
> > > for a reliable way to tell if my speedometer is off at all with the
> > > tire upgrade. I do not have access to a GPS system. What I HAVE done
> > > is to use the tripometer (with tenths), and hold steady at 60 mph (my
> > > speedometer said 60) for one mile while watching my clock. I am
> > > EXTREMELY close to going 1 mile in 1 minute by using this method. Is
> > > this reliable to tell whether or not my speedometer is dead on? I
> > > have NOT changed the speedometer gear yet, or had the computer changed
> > > to reflect the larger sized tires. Also, I am not using my OD (6th)
> > > much on the highway, but when I get up to 65 (the speedometer says
> > > 65), I am running at about 2500 rpms in 5th. Is this bad, or should I
> > > be shifting into the OD (6th)? I do fine with 1st through 5th. Just
> > > not sure what speed or what rpms I should be using 6th. Any help is
> > > really appreciated.
>
> > The (ones that have posed here) older TJ speedometers became correct
> > when 31" tire were put on.
>
> > Your mile per minute is a good base to tell it is close.
>
> > The only other way is to find a measured mile or a friend with a GPS or
> > even ask a cop to pace you because 'you just got new tires and don't
> > want to break the law'. Only a cop's speedometer would be reliable for
> > this, cars can be off too according to tire size.
>
> > I find 'my' engine 'much' prefers to be running at 2300-2500 rpm on the
> > highway which I get with my 4th gear. (have 33's and 3.31 gears) That
> > rpm gives me good throttle control and prevents engine lugging. I also
> > get a pretty stable 11L/100km or 23 mpg running there.
>
> > If I go to overdrive or 5th gear, the rpm drops to 1750 or so at 65 mph
> > which makes for the need of the full gas pedal travel to adjust speed or
> > hold a hill or wind vs a twitch of the pedal in 4th. This low rpm drops
> > my gas mileage by at least 5-8 mpg.
>
> > You can find out easy. Just compare gas mileages when using only 5th on
> > the highway and when using 6th mostly. I have one trip I do lots to get
> > bush camping which is 201 km from gas station to gas station so I have
> > an easy check point.
>
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> > Canadian Off Road Trips Photos: Non members can still view!
> > Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
> > (More Off Road album links at bottom of the view page)- Hide quoted text -
>
> > - Show quoted text -
>
> So, assuming that my speedometer is correct, running approximately
> 2500 rpms in 5th gear at 65 mph will NOT hurt my engine or cause
> increased engine wear? If I were to shift into OD (6th), what is the
> approximate rpms that I should be running so as to not cause lugging
> or increased engine wear?
>
> THANKS- Hide quoted text -
>
> - Show quoted text -
Oh, nevermind. I think I just answered my own question. : D
I am assuming that the approximate 2500 rpms would apply to the OD
(6th) gear as well to prevent increased engine wear and lugging?
> On Sep 17, 11:17 am, Mike Romain <roma...@sympatico.ca> wrote:
>
>
>
>
>
> > Tracie wrote:
> > > Hello all. I have a 2006 Wrangler X with 6 speed manual tranny, 3.07
> > > gearing, and D30 front/35 rear. I recently upgraded my tires from the
> > > stock 215/75/15 to 31/10.5/15 BFG All Terrain T/A KO. I am looking
> > > for a reliable way to tell if my speedometer is off at all with the
> > > tire upgrade. I do not have access to a GPS system. What I HAVE done
> > > is to use the tripometer (with tenths), and hold steady at 60 mph (my
> > > speedometer said 60) for one mile while watching my clock. I am
> > > EXTREMELY close to going 1 mile in 1 minute by using this method. Is
> > > this reliable to tell whether or not my speedometer is dead on? I
> > > have NOT changed the speedometer gear yet, or had the computer changed
> > > to reflect the larger sized tires. Also, I am not using my OD (6th)
> > > much on the highway, but when I get up to 65 (the speedometer says
> > > 65), I am running at about 2500 rpms in 5th. Is this bad, or should I
> > > be shifting into the OD (6th)? I do fine with 1st through 5th. Just
> > > not sure what speed or what rpms I should be using 6th. Any help is
> > > really appreciated.
>
> > The (ones that have posed here) older TJ speedometers became correct
> > when 31" tire were put on.
>
> > Your mile per minute is a good base to tell it is close.
>
> > The only other way is to find a measured mile or a friend with a GPS or
> > even ask a cop to pace you because 'you just got new tires and don't
> > want to break the law'. Only a cop's speedometer would be reliable for
> > this, cars can be off too according to tire size.
>
> > I find 'my' engine 'much' prefers to be running at 2300-2500 rpm on the
> > highway which I get with my 4th gear. (have 33's and 3.31 gears) That
> > rpm gives me good throttle control and prevents engine lugging. I also
> > get a pretty stable 11L/100km or 23 mpg running there.
>
> > If I go to overdrive or 5th gear, the rpm drops to 1750 or so at 65 mph
> > which makes for the need of the full gas pedal travel to adjust speed or
> > hold a hill or wind vs a twitch of the pedal in 4th. This low rpm drops
> > my gas mileage by at least 5-8 mpg.
>
> > You can find out easy. Just compare gas mileages when using only 5th on
> > the highway and when using 6th mostly. I have one trip I do lots to get
> > bush camping which is 201 km from gas station to gas station so I have
> > an easy check point.
>
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> > Canadian Off Road Trips Photos: Non members can still view!
> > Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
> > (More Off Road album links at bottom of the view page)- Hide quoted text -
>
> > - Show quoted text -
>
> So, assuming that my speedometer is correct, running approximately
> 2500 rpms in 5th gear at 65 mph will NOT hurt my engine or cause
> increased engine wear? If I were to shift into OD (6th), what is the
> approximate rpms that I should be running so as to not cause lugging
> or increased engine wear?
>
> THANKS- Hide quoted text -
>
> - Show quoted text -
Oh, nevermind. I think I just answered my own question. : D
I am assuming that the approximate 2500 rpms would apply to the OD
(6th) gear as well to prevent increased engine wear and lugging?
09-17-2007, 11:36 AM
#30
Guest
Posts: n/a
Re: ACCURATE SPEEDOMETER?
On Sep 17, 11:34 am, Tracie <brain...@upstate.edu> wrote:
> On Sep 17, 11:26 am, Tracie <brain...@upstate.edu> wrote:
>
>
>
>
>
> > On Sep 17, 11:17 am, Mike Romain <roma...@sympatico.ca> wrote:
>
> > > Tracie wrote:
> > > > Hello all. I have a 2006 Wrangler X with 6 speed manual tranny, 3.07
> > > > gearing, and D30 front/35 rear. I recently upgraded my tires from the
> > > > stock 215/75/15 to 31/10.5/15 BFG All Terrain T/A KO. I am looking
> > > > for a reliable way to tell if my speedometer is off at all with the
> > > > tire upgrade. I do not have access to a GPS system. What I HAVE done
> > > > is to use the tripometer (with tenths), and hold steady at 60 mph (my
> > > > speedometer said 60) for one mile while watching my clock. I am
> > > > EXTREMELY close to going 1 mile in 1 minute by using this method. Is
> > > > this reliable to tell whether or not my speedometer is dead on? I
> > > > have NOT changed the speedometer gear yet, or had the computer changed
> > > > to reflect the larger sized tires. Also, I am not using my OD (6th)
> > > > much on the highway, but when I get up to 65 (the speedometer says
> > > > 65), I am running at about 2500 rpms in 5th. Is this bad, or should I
> > > > be shifting into the OD (6th)? I do fine with 1st through 5th. Just
> > > > not sure what speed or what rpms I should be using 6th. Any help is
> > > > really appreciated.
>
> > > The (ones that have posed here) older TJ speedometers became correct
> > > when 31" tire were put on.
>
> > > Your mile per minute is a good base to tell it is close.
>
> > > The only other way is to find a measured mile or a friend with a GPS or
> > > even ask a cop to pace you because 'you just got new tires and don't
> > > want to break the law'. Only a cop's speedometer would be reliable for
> > > this, cars can be off too according to tire size.
>
> > > I find 'my' engine 'much' prefers to be running at 2300-2500 rpm on the
> > > highway which I get with my 4th gear. (have 33's and 3.31 gears) That
> > > rpm gives me good throttle control and prevents engine lugging. I also
> > > get a pretty stable 11L/100km or 23 mpg running there.
>
> > > If I go to overdrive or 5th gear, the rpm drops to 1750 or so at 65 mph
> > > which makes for the need of the full gas pedal travel to adjust speed or
> > > hold a hill or wind vs a twitch of the pedal in 4th. This low rpm drops
> > > my gas mileage by at least 5-8 mpg.
>
> > > You can find out easy. Just compare gas mileages when using only 5th on
> > > the highway and when using 6th mostly. I have one trip I do lots to get
> > > bush camping which is 201 km from gas station to gas station so I have
> > > an easy check point.
>
> > > Mike
> > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> > > Canadian Off Road Trips Photos: Non members can still view!
> > > Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
> > > (More Off Road album links at bottom of the view page)- Hide quoted text -
>
> > > - Show quoted text -
>
> > So, assuming that my speedometer is correct, running approximately
> > 2500 rpms in 5th gear at 65 mph will NOT hurt my engine or cause
> > increased engine wear? If I were to shift into OD (6th), what is the
> > approximate rpms that I should be running so as to not cause lugging
> > or increased engine wear?
>
> > THANKS- Hide quoted text -
>
> > - Show quoted text -
>
> Oh, nevermind. I think I just answered my own question. : D
>
> I am assuming that the approximate 2500 rpms would apply to the OD
> (6th) gear as well to prevent increased engine wear and lugging?- Hide quoted text -
>
> - Show quoted text -
Which would probably be somewhere in the neighborhood of 70-75 mph in
6th at approximately 2500 rpms.
> On Sep 17, 11:26 am, Tracie <brain...@upstate.edu> wrote:
>
>
>
>
>
> > On Sep 17, 11:17 am, Mike Romain <roma...@sympatico.ca> wrote:
>
> > > Tracie wrote:
> > > > Hello all. I have a 2006 Wrangler X with 6 speed manual tranny, 3.07
> > > > gearing, and D30 front/35 rear. I recently upgraded my tires from the
> > > > stock 215/75/15 to 31/10.5/15 BFG All Terrain T/A KO. I am looking
> > > > for a reliable way to tell if my speedometer is off at all with the
> > > > tire upgrade. I do not have access to a GPS system. What I HAVE done
> > > > is to use the tripometer (with tenths), and hold steady at 60 mph (my
> > > > speedometer said 60) for one mile while watching my clock. I am
> > > > EXTREMELY close to going 1 mile in 1 minute by using this method. Is
> > > > this reliable to tell whether or not my speedometer is dead on? I
> > > > have NOT changed the speedometer gear yet, or had the computer changed
> > > > to reflect the larger sized tires. Also, I am not using my OD (6th)
> > > > much on the highway, but when I get up to 65 (the speedometer says
> > > > 65), I am running at about 2500 rpms in 5th. Is this bad, or should I
> > > > be shifting into the OD (6th)? I do fine with 1st through 5th. Just
> > > > not sure what speed or what rpms I should be using 6th. Any help is
> > > > really appreciated.
>
> > > The (ones that have posed here) older TJ speedometers became correct
> > > when 31" tire were put on.
>
> > > Your mile per minute is a good base to tell it is close.
>
> > > The only other way is to find a measured mile or a friend with a GPS or
> > > even ask a cop to pace you because 'you just got new tires and don't
> > > want to break the law'. Only a cop's speedometer would be reliable for
> > > this, cars can be off too according to tire size.
>
> > > I find 'my' engine 'much' prefers to be running at 2300-2500 rpm on the
> > > highway which I get with my 4th gear. (have 33's and 3.31 gears) That
> > > rpm gives me good throttle control and prevents engine lugging. I also
> > > get a pretty stable 11L/100km or 23 mpg running there.
>
> > > If I go to overdrive or 5th gear, the rpm drops to 1750 or so at 65 mph
> > > which makes for the need of the full gas pedal travel to adjust speed or
> > > hold a hill or wind vs a twitch of the pedal in 4th. This low rpm drops
> > > my gas mileage by at least 5-8 mpg.
>
> > > You can find out easy. Just compare gas mileages when using only 5th on
> > > the highway and when using 6th mostly. I have one trip I do lots to get
> > > bush camping which is 201 km from gas station to gas station so I have
> > > an easy check point.
>
> > > Mike
> > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> > > Canadian Off Road Trips Photos: Non members can still view!
> > > Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
> > > (More Off Road album links at bottom of the view page)- Hide quoted text -
>
> > > - Show quoted text -
>
> > So, assuming that my speedometer is correct, running approximately
> > 2500 rpms in 5th gear at 65 mph will NOT hurt my engine or cause
> > increased engine wear? If I were to shift into OD (6th), what is the
> > approximate rpms that I should be running so as to not cause lugging
> > or increased engine wear?
>
> > THANKS- Hide quoted text -
>
> > - Show quoted text -
>
> Oh, nevermind. I think I just answered my own question. : D
>
> I am assuming that the approximate 2500 rpms would apply to the OD
> (6th) gear as well to prevent increased engine wear and lugging?- Hide quoted text -
>
> - Show quoted text -
Which would probably be somewhere in the neighborhood of 70-75 mph in
6th at approximately 2500 rpms.
