Part # for speedo gear?

[Darel]

'97 12V auto, 3. 54 gears. I'm going to 285/75s and was looking for the speedo gear part number to correct for the taller tires. I've done an extensive search of the archives but no one actually seems to list a part #. A couple of people said they got their auto-equipped truck to within 1/10 of a mile with 285s, what's the part # for the speedo gear? I probably have one lying around since I've had about 7 different tire/gear combos in my Jeep TJ.

Thanks!

Darel

 

[Rude Ram]

I don't have a part #, but it is 31 teeth. I just had mine out and put in a 30 for my new 265/75.

 

[Darel]

Then the part number will be 31T. Thanks a lot!

Darel

 

[Dave Remillard]

Darel;

I've got the same size tires on my rig. I would assume that if the part number is 31T, that I would be able to go to my local DC dealer and get one. Or do I need to special order one somewhere else? Thanks

 

[dremelts]

Darel,



I don't have any first-hand experience with this product but the link below will take you to a site that sells a speedometer re-calibration device (scroll down almost to the bottom of the page).



This is an electronic gizmo that goes in the line from the rear wheel speed sensor. It modifies the pulse signal that the speedometer interprets as mph.



Like I said - I have no experience with it but I seem to recall a post somewhere here on TDR about an article in a previous issue of the TDR magazine that reviewed this or a similar device.



http://www.superlift.com/new.htm

 

[Boldt's Wagon]

The 97, 3. 54, auto has a 31 tooth gear as original with 245/75 tires. I installed a 30 tooth, part number 52067630, for 235/85 tires.



You will want a 29 tooth gear for 285/75 tires. The part number will be different. The friendly man at your dealer's parts counter will be glad to look up the part number for you and order it.

 

[bowhunter]

What tooth speedo gear do you need for 315/75/16's?

 

[Big_DQ]

Kurt, I don't know what the part# is but you can have the one out of the Toy if you want it. I don't use it any more.

Don

 

[bowhunter]

Thanks Don... .



I need to come over to see how the new shop is coming..... If I can still remember how to get to your house... its been a while since I've been over. I'll give you a call this evening.



Kurt

 

[Boldt's Wagon]

Bowhunter: I calculate a 27 tooth gear for 315/75x16 tires.

 

[bowhunter]

Thanks Boldts--



I can't decide if I should put a new gear in or not... . I'm putting less miles on if I leave the stock gear in.



Big DQ has offered his speedo gear to me, I'll definitely put it in.



Its nice to know exactly how fast you're going and how many miles you got out of the last tank of fuel.



I do a lot of highway driving, and its real easy to not pay attention and run over 75mph, if you are not careful. Don't need anymore tickets!



Thanks