I'm new to owning a Wrangler and know nothing about axles or gearing. I have a 4D Rubicon with auto transmission, stock axles (Dana 44 I believe), and stock 4.10 gearing. I am currently running 37" tires (no plans of ever going larger, but could possibly drop to a 35" in the future). Based on countless searches through the forums it seems I'd benefit from regarding down to either a 5.38 or 5.86.

Can the Dana 44 handle 5.38 or 5.86? Are there benefits or downsides to either of these? Which would you recommend and why? I really appreciate any help the community can offer. I'm hoping your experience can point me in the right direction.

 

Welcome to JKF.. Nice Ride.. Curious; what is your intended or planned use for your Rubi? 4.10s w/35s is what I run with a 6spd .. upgraded from 3.73s when went to 35s. 70 mph is at the 2200 rpm level on the highway.. IMHO- Unless you are climbing mountains you won't need the 5's and you will suffer a loss in MPG. If you plan on 40s then 5's would be feasible.

 

I have never seen a set of 5.86 gears for a jk dana 44. 5.13 is typically the sweet spot for 37's

 

Yeah I would go with the 5.13's but you may find them a little slow on the highway if you drop back to 35's. Sweet spot (IMO) for 35's is 4.88's

 

With my 3.8 Auto, I am running 5.38's and 37's (with a 'measured' height of 36"), which has it just over 2400 rpm's at 70mph. Maybe a bit higher than some other folks would prefer, but works just fine for me.

 

It is my daily driver, but I also live at the base of the mountains and spend a fair amount of time in the back country, but definitely not rock crawling. I also, spend quite a bit of time on the highway/freeway.

 

When you went to 5.38s did you notice a significant change in the feel? Mine is pretty sluggish currently. Seems quite a few are recommending 5.13's. Is there a reason you went with 5.38's? Based on your response above, I'm leaning towards 5.38. Thanks

 

Nope, 5.38's weren't that big a change at all...

I was already running 5.13's and 35's, the bump to 5.38 and 37's came as part of an axle swap. But as far as a 'significant change in feel' goes, I think a lot of it depends on your own personal opinion/perception. Some folks go into a gear change believing it will be instant V-8 power - instead of just bringing the rpm's back up to a more usable level. But just looking at the numbers, there's only like a 110 rpm difference between the two ratios at freeway speeds, you'll be good either way you go.