4.56, 34 TSLs, and speedo gear calculation.

Does anyone have this gear/tire size combination? If so, what speedo gear do you have, and is it working for you?

From what I can find, both here and on other Jeep-related sites, my ring/pinion and tire size seems to necessitate a 38-tooth speedometer gear. I found a calculation on a site someone posted here somewhere that equated to a 35 or 36-tooth gear:

((63360/tire circumference)*gear ratio)/76.3 = number of speedometer gear teeth= tooth count

or,

((63360/(tire diameter*3.14159)*gear ratio)/76.3 = number of speedometer gear teeth= tooth count

I don't know the accuracy or validity of this calculation however.

I've changed from 3.07s to 4.56s, and from who knows what was originally on it for rubber to 33.8 inch TSLs. Any suggestions based on first-hand experience would be welcomed.

your calculations for a 38-tooth gear look spot on to me.

I've seen too many charts. But, thanks for showing me another one nonetheless.

W,JW.

Just looking for opinions based on experience.

Go to partsmike.com. Pull your stock gear, count the teeth (there were 3 different ones stock), call the number on the site, tell them your stock gear count, what size tires and gears, e will find out the right one for you. Good guys there. I got mine for a very reasonable price and it's more accurate than it was stock.