getting tired of 8.25 pinion problems

I bought my 97 XJ with a noisy rear end knowing that I would have to change it. I bought a junkyard 8.25 and put it in. I checked the pinion before I put it in and it turned smooth as glass. Now its rough too, in roughly 3000 miles, but the noise is not as bad (yet). When shopping for a 2nd XJ I test drove another with a noisy 8.25. That's 0/3 for 8.25's.

At this point I'm questioning even trying another 8.25. Maybe my bad luck has ended and the next one will be good. Or maybe I should try rebuilding what I have or going to a D35 or something else. I don't want any blue oval parts on my Jeep.

Any thoughts?

Do the D35's get noisy pinions also or do they just blow up?

I wouldn't go D35, that's a downgrade. If you're opposed to the 8.8, that leaves the 44 as your only option without a lot of fab work.

Remember junk yard parts are used. I'm not sure how many miles are on your rig, or were on the one you got the new rear end from, but its possible that it was just bad luck and you snagged another one near the end of its life.

What about rebuilding one of the ones you have? Then you know the parts are good.

My '00 got a noisy pinion at about 65k(I bought it at 47k). I didn't do anything about it until about 95K when I re-geared the axle. Now it's at 130k and no further problems. I'd say go ahead and rebuild it.

Is a crush sleeve eliminator available?

Yes ratech makes them.

md21722 said:

I bought my 97 XJ with a noisy rear end knowing that I would have to change it. I bought a junkyard 8.25 and put it in. I checked the pinion before I put it in and it turned smooth as glass. Now its rough too, in roughly 3000 miles, but the noise is not as bad (yet). When shopping for a 2nd XJ I test drove another with a noisy 8.25. That's 0/3 for 8.25's.

At this point I'm questioning even trying another 8.25. Maybe my bad luck has ended and the next one will be good. Or maybe I should try rebuilding what I have or going to a D35 or something else. I don't want any blue oval parts on my Jeep.

Any thoughts?

Do the D35's get noisy pinions also or do they just blow up?

Click to expand...

JY units are generally high milage. And if you have a lift, there are extra forces at work on the pinion bearings.

I have rebuilt a couple. The ones I had were high milage and were growling in drive, not coast. You replace the bearings and races, set your preload, and call it good. They are smooth afterwards. The one in my '01 was setup before I got it, and they left a milkshake back there to boot. At some point I will rebuild it, but not for a while. Most days I can't hear it over the 33" ATs.

I'm not worried about a little noise. There are literally hundreds of thousands of Corporate 8.25's out there in 27 and 29 spline flavors. I've had them in a Volarie, a D100 Van, and now Jeeps. They are workhorses.

I don't know what your trucks mission is. Mall crawler or double duty, but the Dana 35 is a down grade from the axle you currently have.

~Ron

I know the D35 is not as strong, but I've had good luck with the one under my 01 XJ. The 01 XJ is not lifted and runs 235/75R15. The 97 XJ with the problematic 8.25's has a 2-3" lift and 30x9.5. For both, most miles are highway with some fire trails or easy/moderate trails.

I pulled the differential out of my HP 30 today to change the axle seals and found the left carrier bearing is pitted. The right looks fine. I will probably try rebuilding one of the 8.25's to get some experience, so I can do another like my HP 30 when the time comes. That way I know the condition and don't end up with a garage full of axles. Is it easier to do on jack stands or under the vehicle. I have one of each. And which one to rebuild?

Factory 29-spline LSD on jack stands. Housing has surface rust in the housing but the R&P, spider, and side gears looks good. Makes a LOT of noise starting at 20MPH. Has a pinion leak. Had tons of metal in the fluid when I got it. All <1mm. Just idling with the rear off the ground if you open one of the back doors and put your head in you can hear it.

JY 27-spline open under vehicle. Has clean housing, but I had to clean out one of the axle tubes because I got it with the brake line removed. Much quieter. But the R&P, spider, and side gears don't look as good. Also, it seems to have 3/16" toe-in. I am not sure how this is possible unless its slightly bent.

I can also mix and match to make one good axle.

I would rebuild the 29 spline.
When you replace the pinion bearings, there are shims for depth under the inner bearing and probably under the race for the inner bearing. You will need a long drift to remove the races.

Make darn sure to get the races and bearings seated before you try and do any measurement.

You will need to make a setup bearing for the inner and outer pinion bearing. Just clearance the inside of a good bearing.

The carrier adjustments is done with a spanner or a tool slid down the axle tube. I made a spanner.

After you have made sure your pinion depth is correct. You will need a huge pipewrench to hold the pinion yoke while you tighten the pinion nut. Do NOT use a Gun! Use a long bar wrench to tighten the nut! It will take effort.

~Ron