jpjk2009

Super Stroked,
Have you heard good things (quality job) about them?. The price difference between 249drivetrain and other stores is huge.

OpenTrackRacer

I've been looking into this very question and I'll almost certainly be going with 5.38 gears on my Rubicon automatic when I move to 35" tires (which will hopefully be next week).

MOPWR2U

Some people still JUST DON'T GET IT. We are not regearing these Jeeps to get a lower first gear. We are regearing these Jeeps because top gear on the highway with the auto trans is way way way too tall. Top gear in high range has nothing what-so-ever to do with the low range gear ratio of the T-case. With the 4:1 T-case in the Rubicon the stock 4.10 gears would be fine for low range off road use, even with 37" tires, or perhaps even 40" tires. Low range isn't the problem.

How many broken 5.38 gears have you seen in a JK? Just curious, because I haven't even heard of one, let alone seen one.

OnBelay

Another vote for 5.13. Best mod I ever made.

With 4.88, the transmission still might hunt for gears a bit.

Super Stroked

I've asked a few people in the diesel groups in with and they had good experience. I haven't personally delt with them or even priced them for anything yet. Are they more or less than others?? I was going to head there this coming week to look at my F-250 and check it over for a noise i can't track down and to discuss gears for as well.

NGINIER

Planman is right, regear as low as you can. The trick is to keep your RPM at or above 2500rpm at highway speeds. I have 35" km2's and 5.13's and i love it, but with any 37, or even a larger 35, I'd want more gear.

Go 5.13, but if you've even lusted over 37's, get the 5.38's. That'll probably seem a little steep with 35's(especially if you do 75mph+) but you won't regret it later.

kfletcher

I have 5.13s with 35s and very happy, would not want anything less. Even with highway driving its what I would want. Had installed at 249 drivetrain in Houston and have no problems. It looks like he does alot of installs so he has the experience.

JKRoobi

I'm curious about this too because once I regear, I've always leaned toward 5.13's because I figured the 5.38's in a d44 wouldn't be too smart for strength reasons...but so many people are running them

So yeah, how many of you busted up a set of 5.38's?

Stoneaxe

I would have to say 5:13's if you plan on going offroad at all. But, it sounds like you have quite the commute. If I were in your shoes I might consider 4:88's.

Are the tires you're getting actually 35's? Mine measure 33.5" or so but are listed as "35's" with a manufacturer indicated size of 34.6".

Also, keep in mind that the Superchips (or other programmer) will change your experience with new gears/tires dramatically as it adjusts throttle/shift points/etc to account for the geometry changes.

Danny4652

As I said before, I have the exact same set up as you. On the highway, in OD, at 70-75 mph I'm at 2300 rpms (give or take a few). I haven't run a full tank of gas primarily on the highway yet but I can tell you that where I live I hit the highway to go most places and I'm getting anywhere from 17.1 - 17.3 mpg. It has excellent power and passing ability. I would stick with 5:13's. If I ever get rid of this Jeep, I would do all over again.