I have a Jk Wrangler 3.8l v6 auto. After reading the forum, it seems that 5.13 gears are the preferred gears for 35" tyres... my other question is that I wanted to fit an ARB rear only air locker and have mixed feedback about the suitability of 5.13 gears and the air locker.... anyone have any thoughts...?

Also, will there be a problem if i fitted air locker to the front diff being a D30 5.13 gears as well?

 

I just had ARB locker (35 spline) and 5.13 gears installed in my rear 44. I have not heard of these suitability issues so what are they? So far it rides great and a big improvement over stock but I'm still breaking them in.

I decided not to invest in my d30 and just run it open till it breaks or when I can afford a Pro Rock 44/60. A locker in that weak axle is a time bomb IMO.

 

There was something i read that the 5.13 and lockers were getting stuck and not disengaging etc....

i agree that the d30 with lockers is not a good idea.

how do you find the 5.13 in the front and rear?

do you have a 3.8l v6 auto?

revs ok at freeway speed of 100kph?
what is your current mpg usage?

 

Post 33 in this thread will answer a lot of your questions on gearing a JK automatic:
https://www.jk-forum.com/forums/show...=1#post2147185
The RPM charts are great. Be sure to use the actual measured tire height, not the mfg's spec or sidewall height.

I'll toss out another vote for not dumping a grand into a selectable locker for a d30. If you want something up front, look at a $250 lunchbox or a $390 TrueTrac and call it a day.


Post it if you find it again. Other than a few air line and o-ring issues, I haven't seen many negatives at all for the arb.

 

You shouldn't have any problems what so ever with lockers and 5:13 gears. there are rigs all over the country running this same set-up. The ring gear is thinner with 5:13 gears compared to the higher gear ratios. I am running 5:13's. front is a D30 with an OX cable locker and the rear is a D44 with LSD from the factory pushing 35's and I haven't had any issues so far. Just my .02

 

I have zero problems with 5:13s and ARB air lockers in my D30.

 

Yes, 3.8 v6 auto. I haven't had the gears in long enough to test for mileage yet. Breaking in still. I'm sure they will be a big improvement over stock. Revs at 100kph (63 mph?) is around or under 2000 rpm. At 113kph (70 mph) it's right at 2300 rpm.

Also it's great that guys running lockers in front are having success. When I eventually upgrade, I just don't want to buy twice.

 

I wonder if they were engaging/disengaging under load. You can only switch when there is no load.

 

I had 5.13's installed w/ an ARB locker and have had zero problems. The Jeep does drive a lot nicer w/ the 5.13's. Seem I don't have to stand on the gas pedal to get it to shift gears anymore. The superchip setup may have helped that though. But, before the superchip, I found the acceleration and shifting to be better.

 

5.13 in your front D30 diff with air locker??? You're brave..... How is it? What sort of driving do you do???