axle opinion

im looking for everyones opinion on the 8 1/4 rear axle. my 89 XJ has this rear end in it. i dont know much about it. my plans for the jeep include ARBs and 35s. i will be running sand, some rocks, trails, mud etc. will tjis axle hold up or should i upgrade?

Many people use the 8 1/4 for the uses you describe. At least you don't have the Dana 35. Of course the Ford 8.8 (Explorer) is a common upgrade that you can find a lot of informaiton on easily. But the Corp 8 1/4 should be fine.

The 8.25 is a good axle, I used to have one under my XJ before I went 8.8. The tubes are 3" vs the 44's 2.75

I've been running 35's on a 29 spline 8.25 with 4.56's for years, i did switch to AlloyUSA shafts and it's got a PowerTrax No-Slip. Never had a problem thus far. -B

Convert it to a 29 spline. the only drawback to yours as-is is the 27 spline shafts. You convert to 29 spline and you will be equal to or better than the D44 and nearly the equal of the ford axel, except for the disc brakes. The Ford axel IS NOT bolt in, spring and shock mount are different and it is 1 1/2" narrower. D35 to 8 1/4 disc swap and 29 spline, cheapest and easiest way to go. With plenty of strength for anything short of competition rigs.

what spline is yours? i take it the 8.25 was swapped in because it was not a factory option in 1989. jeep was still AMC then and the 8.25 is a chrysler product...

stewie said:

what spline is yours? i take it the 8.25 was swapped in because it was not a factory option in 1989. jeep was still AMC then and the 8.25 is a chrysler product...

Click to expand...

Was going to say this - no XJ came stock with an 8.25 till 91 or 92, I believe it was 92.

If you have a 29 spline I think you'll mostly be fine, though this says you want to upgrade shafts before putting a locker in it. If you have a 27 spline you probably should upgrade to 29 spline shafts - you need the shafts, side+pinion gears, and carrier to upgrade, and will have to reset your carrier preload and backlash after swapping the carrier. Might as well replace your bearings while you are in there. At least you will know the pinion depth is already right though. Heck, if you're going to be locking it, get a full case locker for a 29 spline axle and you'll only need to get the shafts to finish the upgrade.