What gears, if any needed on my TJ after bigger tires

[BlueTJ]

What gears should I run on a '03 TJ with 33" tires. I've been told everything from leave the 3.73's in there to 4.10's to correct the change in speedo, to 4.56 or 4.88's to get the best performance. It's just a daily driver no off roading planned.

 

[Snitty]

with 33s, if you have 3.73, you should be ok.... but going to 4.10 would not be enough of a change to make enough difference... if you do... go 4.56

 

[Bounty__Hunter]

Do you have the 4.0L and auto? Or 2.5L and auto?

Either way 4.56 is the only way to go. If you've got the 4.0L you may be fine without regearing, try it and see how you like it.

 

[BlueTJ]

I have the 4.0L with the auto. The pickup seems like it could be a little better with the new tires.

 

[Junkpile]

The pickup probably is better with the taller tires, especially in the mid-rpm range, right? Inline engines produce on average 30% more torque than a comparably sized V configuration engine. You're 3.73s and short tires were letting the engine turn up too fast to take advantage of the engines inherent "sweet spot" on the tach. The 4.0 turns up alot better than the older 258 and makes power a little higher up, but Jeep installs a torque converter with too low of a stall. In the factory configuration, you will never see the real value of that engine. I know it doesn't sound right, but I bet a slightly higher stall converter and firming up those shifts would make your Jeep where it would surprise quite a few "fast" cars. But that's on the street. To restore proper gearing for slow speed wheeling, you should follow Bounty_Hunters suggestion and install up to a 4.56.

 

[BlueTJ]

Sounds good, Thanks for the help guys. I will have the Jeep in the shop next week to get the 4.56's installed.