What gears to use in the WJ?

[206WJ]

Well, I think it's time to re-gear. The problem is that I don't know what to go to.

My jeep is a WJ with the 4.7 HO Cams, NV242-HD, and 5-45RFE. I'm running 285/70/17's right now but may go to 305's later. I currently have the factory 3.73 gears, and keep it in 2wd 90% of the time.

I am not having any gas mileage issues (It's a heavy lifted jeep), or high RPM;s since I have 2 Od's in my Tranny. I do however have a LOT of extra weight, and it feels under powered from time to time.

Should I go with 4.10's or 4.56? I'm thinking of the 4.56, but not sure as I have never done any gearing before. This is for the most part a DD also. Any help or advice would be greatly appreciated. Thanks!!

 

[iluv83vettes]

http://www.4lo.com/4LoCalc.htm

Start with stock tire size and make sure to convert from metric size with aspect ratio to diameter.

Here is a converter for that

http://www.dakota-truck.net/tirecalc/tirecalc.html

 

[206WJ]

http://www.4lo.com/4LoCalc.htm

Start with stock tire size and make sure to convert from metric size with aspect ratio to diameter.

Here is a converter for that

http://www.dakota-truck.net/tirecalc/tirecalc.html

Thanks! I've done those, and it comes to about 4.39 ish on a few different ones. That's partly why I cant choose.

 

[jeep-N-montero]

With a v8 and 33's I would go with 4.10's, for 35's go with 4.56's, I have no idea what those silly metric sizes are.

 

[iluv83vettes]

Thanks! I've done those, and it comes to about 4.39 ish on a few different ones. That's partly why I cant choose.

With 4.39 as what you come out with, I would go with 4.56. That way you can cover the extra weight of the tires as well as whatever other crap you are gonna add to it. When you start adding bumpers fridges whatever, the little bit of extra gears will help. If you aren't adding any extra weight and drive mainly on mostly flat highways, then 4.10 should be fine.

 

[madZJ]

Didn't the diesel export WJ come with 4.28 gears?

 

[206WJ]

With 4.39 as what you come out with, I would go with 4.56. That way you can cover the extra weight of the tires as well as whatever other crap you are gonna add to it. When you start adding bumpers fridges whatever, the little bit of extra gears will help. If you aren't adding any extra weight and drive mainly on mostly flat highways, then 4.10 should be fine.

I've already added a whole bunch of weight to it. Front bumper, rear bumper, Winch, OBA, Long Arms (Very heavy,) and my rear storage with fridge/freezer, I'm probably going with 4.56

 

[Stumpalump]

I've never heard anybody say they wish the gears they put in weren't so low but I've heard many times I'd wish I had gone lower. With the overdrive you have 4.56 is it. Make sure you put thick steel aftermarket diff covers on at least the Dana 30 to keep the case from flexing.

 

[newimage]

Yup 4.56 but with 35s I would go 4.88 because of your 5 speed auto tranny (same as mine) and really depends on the type of wheeling you do.

 

[Stumpalump]

4:88 is as low as you can go on Dana 44's and still have strength. 4.56 is it for Dana 30's. The pinion gear is tiny and weak if you gear them lower.

 

[jeep-N-montero]

Yup 4.56 but with 35s I would go 4.88 because of your 5 speed auto tranny (same as mine) and really depends on the type of wheeling you do.

Actually, he would not like it very much with a v8 and 4.88's unless he was running 37's.

 

[206WJ]

I've never heard anybody say they wish the gears they put in weren't so low but I've heard many times I'd wish I had gone lower. With the overdrive you have 4.56 is it. Make sure you put thick steel aftermarket diff covers on at least the Dana 30 to keep the case from flexing.

That's a good point, I already have the ARB cover in the front, since I'm adding the locker with my new gears.

Yup 4.56 but with 35s I would go 4.88 because of your 5 speed auto tranny (same as mine) and really depends on the type of wheeling you do.

I don't want to go any higher than 4.56. I'll run into strength issues with anything higher than that.

4:88 is as low as you can go on Dana 44's and still have strength. 4.56 is it for Dana 30's. The pinion gear is tiny and weak if you gear them lower.

It's for the 30 front, and the 44a in the rear.