I am making plans to regear my '10 Rubicon 6speed to either 4.88 or 5.13. I had planned on the 5.13's to make up for my 37" coopers and ease towing a pop up I purchased (3200 gvrw). I was advised to do the 4.88 because the ring and pinion is stronger due to size and tooth count.

Any real world input would be appreciated.

I do rock crawl frequently, and have a pro rock front housing and chromoly shafts, and a bone stock rear rubicon 44.

 

The difference between 4.88 & 5.13 gears is wholly dependent on your tendency to slam that skinny pedal. Yes, the 4.88 gears are stronger but not enough to worry about.

Since you're running the 3.8 and want to roll on 37's then the best bet is to get the 5.13 gears; especially considering you're also towing stuff with it.

 

My understanding is that the strength issue with 5.13 gears is primarily related to the Dana 30's on the non-Rubicon JK's. Is that correct?

 

Ye your at correct th3 D-30 Pinion is smaller then the D-44 pinion

I am running 5.13 gears on a 3.8L with manual transmission I a Tera-30 for 4 years now.. you want to avoid wheel spin with the chance of them gripping quickly, the shock is usually the killer

 

I ran the 5.13's in my JKU, automatic, 35's and a Sprintex Super charger for 3-4 years in my Dana 30, no problems just payed attention to control the skinny pedal. I just removed them since I put the 6.0 LS in and they look like new. In fact I have them for sale in the for sale section

 

I generally recommend a 4.88 being the limit in the front for a dedicated wheeler with a D30, but with a Rubicon front 5.13s are fine. I've put a Rubicon JK with 5.13s through some things that you wouldn't and they held up. Yes, 5.13s are definitely weaker than a 4.88, but with lightweight, wussy motor you're good to go, and a 3.8 needs all the help it can get.

Make sure and get good gears and have someone with a good reputation do the install, the quality of the setup is key.

 

It's even more important that you put a heavy diff cover on to support the center sections. There lots of guys out there beating on 5.13 in a D30 with no issues.
The D30 can also handle a RIPP supercharged 3.8 with no issues but like everything else it has a breaking point. You can even break a D60 if you are not careful...

 

So the OP said they are running a ProRock front housing... so that would be a D44. Not sure why the discussion went to D30?

 

Haha that we my fault, I focused on waddle's question

 

sleeve the axles and run 4.88s youll be in business than