silentgi77

Thanx in advance for reading my novice question I have a 2012 jk unlimited (not rubicon) and I was wondering what front and rear axle I have stock. I read a few places that I have a dana 30 front axle and a dana 44 rear axle, please if you know and are reading this, verify. I have gotten unclear information from the dealer and other websites. The reason I ask is that I have 3.21 gears and 33 inch tires with 2 inch coil spring spacers. I would like to upgrade to 4.10 ring and pinion so I can crawl slower in first and use my 6th gear which I can hardly use except on flat or decline roads. Also if anyone can recommend a cheap quality bearing kit that I need to swap the gears that would be great, thanks!

familytime

That's the most common set up from factory.Some early model JK's came with a Dana 35 in the rear

silentgi77

So is it possible that I have a Dana 35 or are you referring to the 2007 fiasco when they had a few different axles types installed in the beginning of that year? Sorry to press you, I'm just afraid of ordering gears that will not fit, thanks for the reply btw

OH9JK

Your 2012 non-Rubi will have a Dana 30 in front and a Dana 44 in the rear.

ThreadHijacker

see pic

onetanjk

I have the same model, yes 30/44 with 3:21.

If you are qualified to change the gears yourself (not easy), people are selling 4:10s all the time from Rubicons, you do have to order one probably new for the front 30 however.

If you are having a shop do the install skip 4:10 and go to at least 4:56 or 4:88. Same costs and leaves you set up for 35 tires or more.

Remember to get a procal to config everything. If you are going to wheel a lot just upgrade the front axle before putting more money into it. I regeared, reinforced now I am probably going to upgrade my axle out and waste all that money spent earlier. If you are not sure, just get the procal $150, 3:21 and 33 inch tires on the Penstar are fine until you are sure what level of mods you want for her. Good luck. I would have saved a lot of money if someone gave me this advice.

OH9JK

4.10 will require a different carrier...


Dana Carrier Breaks:

Dana 30 - 3.54 and down; 3.73 and up
Dana 44 - 3.73 and down; 3.92 and up

silentgi77

Thats awesome, thanx. I was able to pick up a dana 44 4.10 rubi set for 70 bucks, just need to find a dana 30 set and some bearings, then its off to finding lockers.

pirate

Just watch what carrier you use, the rubi has a 32 spline and all other have 30 spline axles.

Dynatrac

Sorry but this this could be confusing information. The carrier breaks are correct but not for a JK (or TJ Rubicon) application.
You'll need a new carrier for your front 30, but you'll be fine with the rear carrier.
All JK 44s use a 3.73 down carrier. The 4.10 and up gears are all what is known as 'thick' gears and don't require a different carrier (3.92 is an odd gear set and not relevant). Regardless of whether they are 3.21, 4.10 or 5.38, they will all fit on your rear 44 carrier.