Rear wheels clunk when spun in neutral, what to check?

[andykwells]

2003 Explorer with Limited slip diff. Up on jacks, in neutral, if I spin either rear wheel forward or backwards, there is a clunk from the driveshaft or rearend, about every third of a spin of the wheel. Not enough to stop it turning, but enough to easily detect it.

It has a growl from 10 mph on up, gets louder when off the gas. That's why I had it up, looking at rear hubs.

What should I look at first? Does it sound like the rear end, ujoints, transfer case or transmission?

Thanks for any advice.

 

[Dave8338]

Could be many things. As you mentioned, U-joints, worn ring and pinion gears, spider gears, clutch packs that are worn, and there will always be a little bit of slop when rotating from forward to reverse when there is no load on the wheels.

 

[360cid]

Sounds to me like a u-joint. They can actually "sqeak" as well when going bad and create a vibration at certain speeds which you did not mention! But these X's have solid mounted third members, so the vibration may not exist with them! :scratch:

 

[andykwells]

You know, I realize I never did follow up on this. 5 years later, I'm searching the forums for some other help on same Explorer and I thought to check my posts. Anyway, in the end I think I changed the rear diff fluid and beyond that, never did anything else about the noise. It still has a rear whine, but it never got much louder. Now it has 265,000 miles on it and I have timing chain issues to deal with.