When I turn, I hear this sort of "whomp whomp whomp" sound from the rear. Happens in either direction. I do not hear it when not turning. It's worse when I turn sharply (I think) but I hear it if I turn the wheel at all. I do need an alignment but I assume it's not just that. I was thinking wheel bearing but as I was trying to Google the issue, I saw a lot of people saying I'd hear a wheel bearing noise all the time. Any ideas? My phone doesn't really record it too well.

Please tell me it's not my diff.

P.S. I want to kick everyone that's talked about this on the internet that's described it as "straight or turning." I have yet to find a reference to anyone having it only when turning that has a useful response to it.

 

Is it when powering through a turn only, or is it whether you're on the gas or coasting. I'm wondering about the diff mount.

 

I'll update after I drive home from work, but I am pretty sure it's whenever the car is turning, gas or not. I'll double check if it does it while coasting and I'll check if pressing the clutch changes it. I'm pretty sure I have checked before and it made no difference though.

P.S. When I describe it as "whomp whomp whomp," I really mean it sounds exactly like that... The only way for it to sound closer to that would be someone sitting back there and pronouncing it. (To my ear, anyway)

 

Hmm ok. I am thinking (and I'm no expert on this - it's only my thoughts) that if it's on the gas only, a worn diff mount might make sense because the combination of applied power and side loading could cause it to shift, where with no power you'd have less of a torquing effect on the mount. If it's all the time, maybe check or just change out the rear diff fluid to be sure it's at the proper level. If you have a leaking seal, which is entirely possible from age/wear/mileage, you could have been slowly leaking fluid over time to the point that it's no longer sufficient to cushion the gears.

 

Okay, I'll check it out, thanks. If anyone knows of anything else that I should look into, please let me know. A friend of mine owes me quite a lot of car work so I'm just gonna have him take a look at and probably change out the bearings.

Does anyone think that this could be a wheel bearing? Or is it too odd for it to happen in both directions?

I will note that I think the noise started off different between left and right, but it sounds the same now.

 

Carrier bearings (where the axles ride) failed on my 300ZX and that was a low rumble at parking lot speeds, building to an F1-car wail by 60mph. Just wanted to mention what I saw when my bearings went - it was completely different than what you're describing.

 

Check and see that your wheel bolts are in tightly. Sounds dumb, but dumb happens...

-Cory

 

I recently replaced the rear rotors and pads. The noise was there before and is the exact same after. I'll take even sounds-dumb suggestions at this point. I'm going to try and get the diff fluid done tonight if I can.

 

http://db.tt/Wve2703

This might help you with the torque specs and such for your rear axles in an AWD. Best of luck. I'm kinda lost on this one...

-Cory

 

And here is one on rear drive axle removal and service.

http://db.tt/uNBhccZ

Good Luck...

Cory