33's for my Jeep

[sigmtnman]

The gearing is essential with the 3.8. The 3.8 has the power at the top, while the 4.0 had it at the bottom. I've found that as long as I put my foot into it when I need to, it performs as well as the 3 jeeps I've owned w/ 4.0s. Granted, it won't spin the tires like the 4.0 would, but who needs that in a jeep?

[1908_Cubbies]

Most of the performance issues can be fixed with gearing... The 3.21 gears that I had in mine brought the suck! I am now running 4.88's (6 speed) and 35's. It is perfect!

[sigmtnman]

Many folks report better mpgs over stock (2-3) with larger tires and better gearing.

[Lumber_Jack]

Most of the performance issues can be fixed with gearing... The 3.21 gears that I had in mine brought the suck! I am now running 4.88's (6 speed) and 35's. It is perfect!

That's what I ran on mine. It was strong on the low end and still ran 80 on hwy no problem.

Recommended tire/gear ratio

37" - 5.13

35" - 4.88

33" - 4.10

31" - 3.73

You can certainly operate outside these perimeters, it's just what I would recommend

[Guest db99wj]

That's what I ran on mine. It was strong on the low end and still ran 80 on hwy no problem.

Recommended tire/gear ratio

37" - 5.13

35" - 4.88

33" - 4.10

31" - 3.73

You can certainly operate outside these perimeters, it's just what I would recommend

I'm curious to see what my 3.73's and 33's will do. So far, limited driving, mostly city, some interstate, no problems, I reset my MPG on the computer and it is about the same, will make sure when I hand calculate it at the next fill up.

[sigmtnman]

Here is a great chart showing the different gears/tire combos:

how many people with 35s have regeared? - JeepForum.com

[Guest Lester Weevils]

Time for yet another dumb question-- After you change tire sizes, what do you do to make the speedometer indicate the correct speed?

[sigmtnman]

a procal module or similar.

American Expedition Vehicles - Wrangler ProCal Module - Additional Vehicle Features and Calibration Tool

Make sure to do this before going to a dealer with bigger tires, else they could void the factory warranty.

[Guest Lester Weevils]

Thanks, sigmtnman!

[sigmtnman]

No problem.

[Guest db99wj]

Some transmission shops will do the recalibration for a fee, I think.

[Guest db99wj]

Here's what you can do with a little extra cash laying around.

http://www.facebook.com/video/video.php?v=478490722372

[Lumber_Jack]

Time for yet another dumb question-- After you change tire sizes, what do you do to make the speedometer indicate the correct speed?

The older models ( mine was 97) measured speed using a plastic gear with teeth that measured transmission revolutions, all I had to do was buy a new gear to match the actual tire size and speedo was corrected.

[Lumber_Jack]

Here's what you can do with a little extra cash laying around.

http://www.facebook.com/video/video.php?v=478490722372

Nice videos, the first one is scary fast for an SUV, I like tue second much better. I did the math one day, if you had about $15k to add on to a new JK you could have an awesome on-road/ off-road jeep. Sooo anyone got about $45k they wanna give me?

[Guest db99wj]

The 07's and up are computer controlled, the procal can change them and I believe the Superchip programmer can as well. The superchip can add a little more HP and MPG with different settings.

[Guest Jasen]

Those rigid led bars sure are nice. Pricey too

[Guest 73challenger]

That hemi jeeps looks awesome. In the future I want Iceland offroad fender flares for my WJ jeep. I think with a 2" lift I could fit 33s. With those fender flares you can run 35s with a 4in lift.

[Guest db99wj]

That hemi jeeps looks awesome. In the future I want Iceland offroad fender flares for my WJ jeep. I think with a 2" lift I could fit 33s. With those fender flares you can run 35s with a 4in lift.

I out a 2" budget boost (spacers) on my old WJ, I got 32's on there and they rubbed the inside of the fender well at full flex, barely. This was with stock wheels. They were close to the pinch seem as well. Some will cut that. With wheel spacers or aftermarket wheels it is definitely possible. The fender flares will help on the outside. There are a lot of kits for the WJ's now. I had a 99.

Edited August 19, 2011 by db99wj