Mileage, Tires, and Speed

I have a 99 xj with 4" of lift and 31s.. anyone know where I can get a speedometer gear set that would accomodate the new tires?

I also have an 88 trail rig Wagoneer with 33s. Are the gears cheap enough that I should buy now and again later when I go to 4.56s next year??

I see them in magazines for Fords and Chevys, just never for Jeeps!
Any guidance would be appreciated

There are lots of charts out there for the right spedo gear to accomediate tires size changes and gears.

www.jeepin.com has one and so does http://go.jeep-xj.info/index.htm

You can get the speedo gear from a dealership. Its under $30.

AARON

From the chart at go-xj, a manual 4.0 with 31s and a 3.07 rear would use a 27 tooth gear. I haven't been able to find one.

jkmhb said:

From the chart at go-xj, a manual 4.0 with 31s and a 3.07 rear would use a 27 tooth gear. I haven't been able to find one.

Click to expand...

The list of parts numbers a little bit below that chart doesn't even show 27 tooth gears.
If they don't make them - and it looks like they don't - you may not have any choices other than regear sooner or just figure out how much you are off and go by that. You may not want to let anyone who doesn't know about that drive your Jeep, though.
I just picked up my 39 tooth gear (35s with 4.88s) yesterday afternoon. I was out the door for $19 and change.

I have a '99 with manual/3.07s and 31" tires. I used the 28 tooth gear, which is available. The speedometer is very close to correct.