Jkbroc

I'm currently running 40x13.5x17's on my a PR44U and a rear 44. I'm working on building my axles I've taken from my 2005 F250 and getting ready to purchase the gears and lockers. Right now with the 5.13s I feel it's not really a much of a change from 37's to 40's but I haven't really put my jeep through the ringer like I have with the 37's. So I guess my question is..... should I jump to 5.38's and is it really that big of a difference compared to 5.13's. Definitely open to opinions on this. I've looked for higher gear ratios but haven't seen higher. It's a not a daily but I still drive around time.

3.6 auto

Tightdog

You need to let everyone know which engine/trans you have. I've got a 2012 auto that I hope to finish installing rock jock 60's with 5.38 tomorrow so I can let you know how that feels

Jkbroc

Sorry on the oversight
3.6 auto.

caryt

5.38's........................................

Tightdog

If it's not your daily driver why not go 5.38 it will definitely be better wheeling

TheDirtman

5.38 unless you drive the interstate all the time and are worried about MPG, which I doubt you are.

Jkbroc

I figure if anyone would know it'll be you.... it's there a higher numerical gear ratio available then 5.38? Haven't had much luck finding anything. And no, MPG isn't an issue at all.

jtphoto JK

5.38 is the highest for D44. I have them with my 3.8 auto on 37s and it's perfect. I run 2100rpm at 60mph. So I would say for you 3.6 with 5.38 and 40s would be around the same.

Jkbroc

I was referring to gearing for the 1 tons I'm building. On gearing charts they have 5.86 and 6.17's which keep me below 3k on the highway at 70mph. I'm going to assume it would be more drastic of a difference from 5.13's to 5.86 or 6.17's vs 5.13 to 5.38's. If I can't get 5.86 or 6.17's I was just wondering how big of a difference it was between the 2.

The thought process was if it wasn't a crazy difference I could just for 5.13's and while having different bolt patterns I could focus on one axle at a time and still be able to wheel in the interim.

jordy

I run mine all over the place, granted it's got the mighty 3.8 currently, and I've gotten as much as 14 on the highway with 5.38's. Throw a headwind or a hill in and we get closer to 10. 5.38's are ideal for the lack of HP as the first sign of an incline and OD kicks out. I don't know that I'd want to go with a "highway" gear with 40's as this seems to be pretty ideal on and offroad.