Hey guys!

About time to beef up! Have recently upgraded my 35" to 37", and I wince every time I wheel them. Currently, it's a 2012 Jeep Wrangler Unlimited Sport 6-Speed with 4" X-Flex kit, with 37" Nittos, as well as poison spyder bumpers and flares, otherwise stock. Dana 30 up front.

I loved the 37's for a week, and already have decided that 40" are for me . I plan to get some use out of the 37's, and this time next year, I will be selling the 37's and I will be going to 40's.

I have researched pretty thoroughly and decided that the PR44 with Dynatrac balls joints, RCV shafts, and ARB locker is the way I want to go. Now -- for my question.

Is 5.38 way too much gear for 37's on this new engine platform? I have looked at the charts, and they suggest that for daily driving, I would be correct. This IS my daily driver (please spare me the "don't get 40's for DD!") and I drive about 15 miles roundtrip every day, 5 of those on the highway.

I do commonly have 2-4 additional passengers, I tow a mid-sized jet ski, and wheel about 2-3 times a week, but I also drive 120 miles roundtrip every other weekend on the highway.

I AM in college, so getting 4.88s now, then 5.38s with the 40's COULD happen, but I would hinder the rest of my build.

What do you think??

 

5.38 is way too much for a 44. 5.13 max in a 44 or its just too small.
U should be looking at a 60 for 40's. 37 is really the max for a 44, even a pr44

 

The size difference bewteen 513's and 538's is almost nothing so you will be good either way.

for 40's i would go with 538's

With the manual you can get away with the 5.13's with 37's and then 40's

David

 

You recommend a pr44 for a build running 40's?

 

I would always recommend a D60 for 40's but we also know many customers running rubicon 44's with 40's

David

 

I see. I was just curious. I will be emailing u for a cage hopefully Monday David. Thanks

 

With the type of wheeling I do (New England) I feel a PR44 would hold up nicely to 40's. I've run locked and geared dana 30's on 35"s, even a locked and geared rear dana 35 on my XJ without a break, just a few spent u-joints.

How much of a difference in strength is there really going to be between a 5.13 ratio and a 5.38 ratio in a D44? What components are the same in a PR44 and an OEM D30, if any?

IF the ring and pinion will be the issue, is it worth considering the Currie Rockjock 60? The price is in the same ball park.

I think 5.13's would be the simple answer here, but I think I'd rather have the lower gear for 40's, and try to save my clutch when wheeling.