Don Nguyen

Lately my car has developed a thumping noise in the rear.

I've heard it could/is most likely the CV joints that are worn out and need replacing. However, I've also heard that it could possibly be caused by worn/bad wheel bearings as well.

The thumping sound only develops during acceleration, and slightly during breaking as well. Is there anyway to test if the joints are bad? IE jacking up the car and trying to move the axle, to see if there's any play in it, etc?

-Don

joey bagadonuts

I've heard a thumping from the rear passenger area. Under acceleration it was quite noticeable from, say, a standstill to 30 mph. Once you get going, it seems to go away but as soon you lift off the throttle, it returns. Sound familiar?

Bad CV.

Larry Herman

Actually you can check both. With the car up in the air, grab the suspect wheel at 12 & 6 and push/pull really hard. Then do it again holding it at 3 & 9. If it moves AT ALL, the wheel bearing is bad.

For the CV joint, get under the car and first slide them in and out to see if there is any roughness or clicking. If so, it is worn. If not, hold the axle right next to the inner joint and try and move the axle in a circle. There should be no play; repeat with the outer joint.

But I'd agree with Joey. Bearing noises are usually constant and grow in frequency and volume with speed. Clunking on turns or acceleration/deceleration is usually a CV joint.

Don Nguyen

Alright, I am waking up early tomorrow morning to pull these things out and drop them off at the rebuilder.

Wish me luck on getting that 340 ft/lb axle nut off

-Don

joey bagadonuts

Good luck but ... are you not going to follow Larry's inspection advice? (I was hoping a knowledgeable 'lister would chime in) Or did I nail the description of the problem? That thumping coming from the transaxle area is pretty distinct.

Don Nguyen

From reading other posts, it pretty much has to be a bad CV joint. The car only thumps during acceleration, and once things have heated up a bit. The 3 of the CV joints, for the two rear axles, are broken. So I am suspecting that the joints also went bad on them. I just want to pull them out and double check to make sure.

My breaker bar keeps bending on me, so I think I need to find a bigger one, in order to get that axle nut off.

-Don

Larry Herman

Get a 3/4 drive breaker bar and socket. Put a 4' pipe (or floor jack handle) over it and it will come off easy as pie.

Don Nguyen

My impact gun actually just took the axle nuts right off. I guess I under estimated my home air compressor

I am trying to figure out the allen head size on the axles now. I thought they were M8s, but they seem like they're smaller than that?