ACCURATE SPEEDOMETER?
09-17-2007, 09:16 AM
#1
Guest
Posts: n/a
ACCURATE SPEEDOMETER?
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.
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.
09-17-2007, 09:38 AM
#2
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 trip odometer should be close. You can also use the mile markers on
the side of the highways assuming those are correct in your area. I was
told by a local road worker in Wisconsin that they are very accurate,
but that may vary by states.
As far as 6th gear is concerned, using only 5th gear will cause more
engine wear, but it may or may not hurt fuel economy. The only thing to
do there is to test it out. I would think that with the small increase
in tire diameter, you should still be using 6th gear. You do have a very
high gear in your axles, so it is probably worth testing.
Chris
> 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 trip odometer should be close. You can also use the mile markers on
the side of the highways assuming those are correct in your area. I was
told by a local road worker in Wisconsin that they are very accurate,
but that may vary by states.
As far as 6th gear is concerned, using only 5th gear will cause more
engine wear, but it may or may not hurt fuel economy. The only thing to
do there is to test it out. I would think that with the small increase
in tire diameter, you should still be using 6th gear. You do have a very
high gear in your axles, so it is probably worth testing.
Chris
09-17-2007, 09:38 AM
#3
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 trip odometer should be close. You can also use the mile markers on
the side of the highways assuming those are correct in your area. I was
told by a local road worker in Wisconsin that they are very accurate,
but that may vary by states.
As far as 6th gear is concerned, using only 5th gear will cause more
engine wear, but it may or may not hurt fuel economy. The only thing to
do there is to test it out. I would think that with the small increase
in tire diameter, you should still be using 6th gear. You do have a very
high gear in your axles, so it is probably worth testing.
Chris
> 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 trip odometer should be close. You can also use the mile markers on
the side of the highways assuming those are correct in your area. I was
told by a local road worker in Wisconsin that they are very accurate,
but that may vary by states.
As far as 6th gear is concerned, using only 5th gear will cause more
engine wear, but it may or may not hurt fuel economy. The only thing to
do there is to test it out. I would think that with the small increase
in tire diameter, you should still be using 6th gear. You do have a very
high gear in your axles, so it is probably worth testing.
Chris
09-17-2007, 09:38 AM
#4
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 trip odometer should be close. You can also use the mile markers on
the side of the highways assuming those are correct in your area. I was
told by a local road worker in Wisconsin that they are very accurate,
but that may vary by states.
As far as 6th gear is concerned, using only 5th gear will cause more
engine wear, but it may or may not hurt fuel economy. The only thing to
do there is to test it out. I would think that with the small increase
in tire diameter, you should still be using 6th gear. You do have a very
high gear in your axles, so it is probably worth testing.
Chris
> 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 trip odometer should be close. You can also use the mile markers on
the side of the highways assuming those are correct in your area. I was
told by a local road worker in Wisconsin that they are very accurate,
but that may vary by states.
As far as 6th gear is concerned, using only 5th gear will cause more
engine wear, but it may or may not hurt fuel economy. The only thing to
do there is to test it out. I would think that with the small increase
in tire diameter, you should still be using 6th gear. You do have a very
high gear in your axles, so it is probably worth testing.
Chris
09-17-2007, 09:38 AM
#5
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 trip odometer should be close. You can also use the mile markers on
the side of the highways assuming those are correct in your area. I was
told by a local road worker in Wisconsin that they are very accurate,
but that may vary by states.
As far as 6th gear is concerned, using only 5th gear will cause more
engine wear, but it may or may not hurt fuel economy. The only thing to
do there is to test it out. I would think that with the small increase
in tire diameter, you should still be using 6th gear. You do have a very
high gear in your axles, so it is probably worth testing.
Chris
> 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 trip odometer should be close. You can also use the mile markers on
the side of the highways assuming those are correct in your area. I was
told by a local road worker in Wisconsin that they are very accurate,
but that may vary by states.
As far as 6th gear is concerned, using only 5th gear will cause more
engine wear, but it may or may not hurt fuel economy. The only thing to
do there is to test it out. I would think that with the small increase
in tire diameter, you should still be using 6th gear. You do have a very
high gear in your axles, so it is probably worth testing.
Chris
09-17-2007, 10:37 AM
#6
Guest
Posts: n/a
Re: Re: ACCURATE SPEEDOMETER?
On Mon, 17 Sep 2007 08:38:45 -0500, c <c@me.org> 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 trip odometer should be close. You can also use the mile markers on
>the side of the highways assuming those are correct in your area. I was
>told by a local road worker in Wisconsin that they are very accurate,
>but that may vary by states.
>
>As far as 6th gear is concerned, using only 5th gear will cause more
>engine wear, but it may or may not hurt fuel economy. The only thing to
>do there is to test it out. I would think that with the small increase
>in tire diameter, you should still be using 6th gear. You do have a very
>high gear in your axles, so it is probably worth testing.
>
>Chris
Your speedo with be off a good bit. You will be going faster than it
records. With 65 indicated you will be doing about 73 MPH. With 3.07
gear it has got to be a bit of a slug at times too with 31's. Below is
a link where you can run some numbers yourself
http://www.snoman.com/HTML/axlecalc_5a.html
-----------------
TheSnoMan.com
>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 trip odometer should be close. You can also use the mile markers on
>the side of the highways assuming those are correct in your area. I was
>told by a local road worker in Wisconsin that they are very accurate,
>but that may vary by states.
>
>As far as 6th gear is concerned, using only 5th gear will cause more
>engine wear, but it may or may not hurt fuel economy. The only thing to
>do there is to test it out. I would think that with the small increase
>in tire diameter, you should still be using 6th gear. You do have a very
>high gear in your axles, so it is probably worth testing.
>
>Chris
Your speedo with be off a good bit. You will be going faster than it
records. With 65 indicated you will be doing about 73 MPH. With 3.07
gear it has got to be a bit of a slug at times too with 31's. Below is
a link where you can run some numbers yourself
http://www.snoman.com/HTML/axlecalc_5a.html
-----------------
TheSnoMan.com
09-17-2007, 10:37 AM
#7
Guest
Posts: n/a
Re: Re: ACCURATE SPEEDOMETER?
On Mon, 17 Sep 2007 08:38:45 -0500, c <c@me.org> 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 trip odometer should be close. You can also use the mile markers on
>the side of the highways assuming those are correct in your area. I was
>told by a local road worker in Wisconsin that they are very accurate,
>but that may vary by states.
>
>As far as 6th gear is concerned, using only 5th gear will cause more
>engine wear, but it may or may not hurt fuel economy. The only thing to
>do there is to test it out. I would think that with the small increase
>in tire diameter, you should still be using 6th gear. You do have a very
>high gear in your axles, so it is probably worth testing.
>
>Chris
Your speedo with be off a good bit. You will be going faster than it
records. With 65 indicated you will be doing about 73 MPH. With 3.07
gear it has got to be a bit of a slug at times too with 31's. Below is
a link where you can run some numbers yourself
http://www.snoman.com/HTML/axlecalc_5a.html
-----------------
TheSnoMan.com
>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 trip odometer should be close. You can also use the mile markers on
>the side of the highways assuming those are correct in your area. I was
>told by a local road worker in Wisconsin that they are very accurate,
>but that may vary by states.
>
>As far as 6th gear is concerned, using only 5th gear will cause more
>engine wear, but it may or may not hurt fuel economy. The only thing to
>do there is to test it out. I would think that with the small increase
>in tire diameter, you should still be using 6th gear. You do have a very
>high gear in your axles, so it is probably worth testing.
>
>Chris
Your speedo with be off a good bit. You will be going faster than it
records. With 65 indicated you will be doing about 73 MPH. With 3.07
gear it has got to be a bit of a slug at times too with 31's. Below is
a link where you can run some numbers yourself
http://www.snoman.com/HTML/axlecalc_5a.html
-----------------
TheSnoMan.com
09-17-2007, 10:37 AM
#8
Guest
Posts: n/a
Re: Re: ACCURATE SPEEDOMETER?
On Mon, 17 Sep 2007 08:38:45 -0500, c <c@me.org> 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 trip odometer should be close. You can also use the mile markers on
>the side of the highways assuming those are correct in your area. I was
>told by a local road worker in Wisconsin that they are very accurate,
>but that may vary by states.
>
>As far as 6th gear is concerned, using only 5th gear will cause more
>engine wear, but it may or may not hurt fuel economy. The only thing to
>do there is to test it out. I would think that with the small increase
>in tire diameter, you should still be using 6th gear. You do have a very
>high gear in your axles, so it is probably worth testing.
>
>Chris
Your speedo with be off a good bit. You will be going faster than it
records. With 65 indicated you will be doing about 73 MPH. With 3.07
gear it has got to be a bit of a slug at times too with 31's. Below is
a link where you can run some numbers yourself
http://www.snoman.com/HTML/axlecalc_5a.html
-----------------
TheSnoMan.com
>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 trip odometer should be close. You can also use the mile markers on
>the side of the highways assuming those are correct in your area. I was
>told by a local road worker in Wisconsin that they are very accurate,
>but that may vary by states.
>
>As far as 6th gear is concerned, using only 5th gear will cause more
>engine wear, but it may or may not hurt fuel economy. The only thing to
>do there is to test it out. I would think that with the small increase
>in tire diameter, you should still be using 6th gear. You do have a very
>high gear in your axles, so it is probably worth testing.
>
>Chris
Your speedo with be off a good bit. You will be going faster than it
records. With 65 indicated you will be doing about 73 MPH. With 3.07
gear it has got to be a bit of a slug at times too with 31's. Below is
a link where you can run some numbers yourself
http://www.snoman.com/HTML/axlecalc_5a.html
-----------------
TheSnoMan.com
09-17-2007, 10:37 AM
#9
Guest
Posts: n/a
Re: Re: ACCURATE SPEEDOMETER?
On Mon, 17 Sep 2007 08:38:45 -0500, c <c@me.org> 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 trip odometer should be close. You can also use the mile markers on
>the side of the highways assuming those are correct in your area. I was
>told by a local road worker in Wisconsin that they are very accurate,
>but that may vary by states.
>
>As far as 6th gear is concerned, using only 5th gear will cause more
>engine wear, but it may or may not hurt fuel economy. The only thing to
>do there is to test it out. I would think that with the small increase
>in tire diameter, you should still be using 6th gear. You do have a very
>high gear in your axles, so it is probably worth testing.
>
>Chris
Your speedo with be off a good bit. You will be going faster than it
records. With 65 indicated you will be doing about 73 MPH. With 3.07
gear it has got to be a bit of a slug at times too with 31's. Below is
a link where you can run some numbers yourself
http://www.snoman.com/HTML/axlecalc_5a.html
-----------------
TheSnoMan.com
>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 trip odometer should be close. You can also use the mile markers on
>the side of the highways assuming those are correct in your area. I was
>told by a local road worker in Wisconsin that they are very accurate,
>but that may vary by states.
>
>As far as 6th gear is concerned, using only 5th gear will cause more
>engine wear, but it may or may not hurt fuel economy. The only thing to
>do there is to test it out. I would think that with the small increase
>in tire diameter, you should still be using 6th gear. You do have a very
>high gear in your axles, so it is probably worth testing.
>
>Chris
Your speedo with be off a good bit. You will be going faster than it
records. With 65 indicated you will be doing about 73 MPH. With 3.07
gear it has got to be a bit of a slug at times too with 31's. Below is
a link where you can run some numbers yourself
http://www.snoman.com/HTML/axlecalc_5a.html
-----------------
TheSnoMan.com
09-17-2007, 10:38 AM
#10
Guest
Posts: n/a
Re: ACCURATE SPEEDOMETER?
Your watch is a bit clunky, but the method is correct.
A stop watch works better. Ignore the odometer, and measure your miles with
the mile markers along the shoulder of all federal and most state highways.
Divide the time in seconds that it takes to travel a measured mile into
3600, the result will be your speed.
Set the Cruise Control at 60. Measure the time it takes to go a mile. Divide
3600 by the time. 3600 / 60 =- 60. 3600 / 52 = 70. 3600 / 45 = 80.
"Tracie" <brainart@upstate.edu> wrote in message
news:1190034987.028338.291940@19g2000hsx.googlegro ups.com...
> 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.
>
A stop watch works better. Ignore the odometer, and measure your miles with
the mile markers along the shoulder of all federal and most state highways.
Divide the time in seconds that it takes to travel a measured mile into
3600, the result will be your speed.
Set the Cruise Control at 60. Measure the time it takes to go a mile. Divide
3600 by the time. 3600 / 60 =- 60. 3600 / 52 = 70. 3600 / 45 = 80.
"Tracie" <brainart@upstate.edu> wrote in message
news:1190034987.028338.291940@19g2000hsx.googlegro ups.com...
> 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.
>
