Rear axle noise

[denaliak02]

ok, i know this has been covered now about 100 times, and i've been reading through numerous search results for the past hour. But, i just came in from the garage and need some advice on where to start...here goes...

I have extremely loud grinding/clunking noises coming from rear axle/differential when turning corners, and when backing up and turning. Today, while backing from a parking space I cut the wheel and it almost wouldn't move. Needless to say, something is in a bind! Here's the history, recently had springs rebuilt/re-arched at local shop, did some minor frame reinforcement(welding/patching, nothing was cut or moved from it's orig location), put all back together.

I pulled the cover to inspect (as recommended by the forum), no metal shavings, R&P look good, G-oil was correct level, no leaks, axle end play seems ok(i tried to move the wheels up/down, L&R, no mvmt), a little slop in spider gears not sure what is 'normal', u-joints ok, tire pressure/size checked, noise remains while lightly hitting brakes. i think that covers it.

anyway, the consensus seems to say that noises while turning is probably bearing failure. Q: Is that the place to start or am i missing a diag. step?

(sorry for the long post)

thanks in advance for input

[ibnfe]

there isn't much to the rearend that can cause this type of problem. If it was the differential or ring and pinion, it would be obvious when you inspected it, as in a gear tooth missing or worse. One more thing that may show you the cause. Get the rear tires off the ground. Spin the wheels individually having someone hold the opposite side (if it isn't posi) and listen for the sound. It may reveal itself and take away some confusion. I've never had bearings cause this problem, but another way you could check is to drive the vehicle long enough for things to warm up, then stop and feel the axle flanges for excessive heat. If the bearings are bad enough to cause grinding and clunking, then they should be fairly warm! Good luck.

[denaliak02]

Thanks ibnfe, for the advice on checkingthe bearing flanges and holding the wheels, i'll try that.

I plan on refilling the diff. (w/85W90), putting it all back together and doing some more listening. Now that i've eliminated the R&P and spider gears being the culprits, i can focus on some other items. One thing I didn't check is the measurements, ie if the axle is perpendicular to the frame. Does it matter where I measure from/to? I doubt that this has changed, but I can check it.

thanks again,
Justin

[Lindel]

Actually it's possible it can be the differential. :( I had an instance with my 87, that the rear diff was making some very interesting noises, and the repair shop (a very good Jeep shop), showed me the broken cross pin, and severly worn spider gears. Made no difference in the way it drove, but noisy as all get out!

[denaliak02]

Yeah, differentials are my weakness, I haven't seen enough 'bad' ones or taken enough apart to really get an idea what to look for. I have a TSM (for an '82) and it has all sorts of diagnostics you can do on one, but i don't have all the tools for that!

[Crazy_Jeepman]

I would venture to guess it to be the wheel bearings I just went through that with my wifes 89 Grand Wagoneer. I could get it rolling throw it in nuteral and it would stop like there was a brake hung up, it howled and clunked. I jacked it up and I could push and pull the rear wheel in and out about 3 to four inches. NOT GOOD!!! :eek:

[denaliak02]

thanks C_J, i'll do that as well, i think i tugged and pushed them in all directions, but i will try these suggestions again.

like everybody here, you want to do a thorough diagnostic before you start throwing parts (and $$) at a problem. Even though i'm sure new bearings wouldn't hurt, i would rather drive the thing than have it on jackstands in the garage....heck, i would rather be fixing something i broke on the trail, than as a result of daily driving. :D