Hello all. I need some input. I have a 2009 unlimited sport. 3.8 4 door. Currently 33" duratracs. Should I do 4.88 or 5.13 gears on the stock axles? I may go 35s eventually, but not anytime soon. Also I am thinking LSD in the back and a manual elocker up front as it is my DD. What brands would you all recommend and other set up options if this would not be a good one. As mentioned this is my DD/weekend warrior. Offroad I do mostly mud, sand, and hills, some rocks, but it isnt my favorite. I have a 2.5 lift (RK stock mod, with Bilstiens). Thanks!

 

Guessing you have an auto? Either ratio would work, just depends on location/usage/needs. This question is asked just about every day, so there are a ton of other threads to read through for more info. (But with a 3.8 4door auto, I'd go 5.13)

You could do Truetracs front and rear to save some cash. If you want a selectable, the e-locker would be a great choice also.

Gear brands don't really matter, base the decision on price and warranty, or just use the brand your installer recommends.

 

Truetracs being LSD, how would they perform in mud? Would it be better to do rear only for now? Would anyone do a lunchbox in the back and truetrac up front? If I could do only one, should I get a selectable locker in the back or LSDs in the back? And yes, its an auto

 

I had 5.13s and 35s and was at 3k rpm at 70mph on the highway. If I did more highway commuting I'd have gone for 4.88s. I also a chose selectable locker.

I've got a manual btw.

Also if your paying to have it done do it all at once and you'll save labor charges unless thats not a issue for you.

 

Your 35's measure about 33.5"? An auto with that setup will be running around 2500 rpm. And maybe 2370 rpm with 4.88's.

Not that you need it since you are already geared, but there are some good JK-specific charts in the faq's at the top of this area.

 

Not a lot of mud around here, so can't really answer that. But there are quite a few guys running them in JK's so hopefully some of them will comment. It's wasn't a JK, but I ran a front truetrac for over 10 years in my last full size Ram, and when the rear detroit exploded, I put another truetrac in the back and ran it for 4 years. Great traction device for all of the terrain I drive, and a much better combo than the front/rear detroits I started with. (for 'my' needs, which included lots of winter freeways up to the ski areas. If I was more in to rocks, full lockers would obviously be better. But I never felt let down by the truetracs)

Plenty of people run lunchboxes up front, since they are not noticeable in 2wd. For the rear, the folks at Dynatrac posted saying that lunchboxes wear out too fast and they don't recommend. Pretty sure that aussie doesn't even make one for the jk rear housing? Assuming that is correct, you might consider a detroit/grizzley back there if you want an auto-locker.

Dynatracs lockers 101 - fairly good over-view:
Project-JK.com - Jeep JK Wrangler Resource » Dynatrac Presents - Lockers 101

 

I never measured them but I'd guess around 33.5.
I used the charts when selecting gears (very helpful). I also went with 5.13s because I knew id eventually move to 37s. I traded the slightly higher highway rpms for more low end on the trails.

You could always try and find someone local who regeared and take it for a spin.

 

Because it sees more highway I think that I am going with the TTs front and back. Im not into huge rocks, so I dont believe that I need lockers (and the prices are pretty substantial for an elocker) I dont really want an auto locker, so I guess I made my mind up. Still torn between 4.88 and 5.13. It is an auto 4 door and will see more highway than offroad, but I do still go off pavement when time (and the wife) allows