rear end clunking

[minitubbed_82lx]

I have noticed that when I let the clutch out I hear a clucking noise coming from the rear. New upper lowers and drive shaft. I got under the car today and noticed that I could rotate the rear end flange about an 1/4 of an inch. Could this be my problem? Any thing else I should look at?

[85mcLaren]

start simple first - check if driveshaft bolts are loose....

jason

[cottonbear]

If you just installed those arms I would be willing to bet you forgot to tighten one of them. With the car weight on the axle make sure all eight control arm boots are snug.

[minitubbed_82lx]

I need to jack the car up and put the jack stands under the rear end and remove the jack so the weight of the car is on the rear end. I have check u joints and driveshaft bolt. Do I need be worried about the play in the rear end?

[86GreenStang]

Clunking in the rear is the sign of a worn pinion and ring gear and associated bearings. Some play and clunking is to be expected if the differential has over 100k miles. It doesn't mean it will need to be replaced right away. It is not hard to rebuild the rear end. You will just need to get the instructions and follow the tolerances.

[minitubbed_82lx]

I will be rebuilding it here soon

[cottonbear]

1/4 is not a lot of slack when you think about the axle.spline play, spider play and gear lash all combined

[minitubbed_82lx]

I will check it all tomorrow but I think the rear end will be rebuilt since I want 373

[minitubbed_82lx]

So the uppers were loose. The bolts on the rear end were the spherical bushings. So j tightened and it fixed the banging. Then I down shifted into 1st and the clunk came back. Think then bushings are shot since I ran the them loose ? It sound worse. even pings some things when going reverse to first.

[minitubbed_82lx]

anyone else have this happen before? Is this the typical sound from loose bushing?

[Mr Joshua]

"Sounds" are user defined. The only way we could hope to discern the problem from the sound is if you made a clear recording of it.
The best way is for you to climb under the car and do a little reconnaissance on the issue. A.K.A. Wiggle s***, take the arms out and inspect the bushings.

[minitubbed_82lx]

I tried moving some stuff but it all seemed ok. I tightened the upper control arms were they attach to the bushings. I noise almost went away. Then came back after some hard driving. When driving I can let of the gas and then give it a little gas and hear the noise. Let the rearend is moving.

[cb84capri]

pull the upper control arm bolts to the frame out and inspect them. those bolts have a tendency to get grooves worn into them.

cale

[minitubbed_82lx]

Nice call I will check that

[86fiveoh]

I am experiencing a very similar noise. Notice anything in reverse? Coincidentally I also have spherical bushings in the upper ears of my rear, I have been suspecting those to be the issue, but I have yet to get under there.

[minitubbed_82lx]

Yes it is also in reverse

[86fiveoh]

What brand spherical are you using?

[minitubbed_82lx]

They look like upr

[86fiveoh]

Same here. Mine only started doing it after I added the spherical bushings and changed rear shocks. Don't think the shocks should do it, which leads me to the bushings.

[minitubbed_82lx]

Mine is a mini tubb setup and I too had wondered if it was shock but leaning toward the bushings since I tightened them and the noise almost went away and then beat on it better hard and down shifted to 1st and boom it came back

[ford427r]

I'm having the same problem, I checked the drive shaft and it's fine. Put my hand on the flange and I have alot of play. The rear end has an Eaton posi with 4.10 gears,racing axles with a T/A cover. Yes, it's been together for 10 years but has not that many miles. Could I tigthen it up some or should I take the cover off and check the gears? I kinda like to get rid of the 4.10s and go with 3.73 or 3.55s, maybe that would cut down on the drone from the flowmaster mufflers.

[mustangxtreme]

My stock 7.5 had a lot of slop and i drove it over 180,000 miles. It always made a clunk and I bought the car with 60,000 miles on it.

[MAD MIKE]

Check the spherical bearings themselves. They should not be easy to move. If you can turn or spin the mono-ball easily it is worn and may be contributing to the clunk sound. And make sure that the bolt holes have not become oblonged from driving with loose bolts.

If the gear oil is past its expiration/mileage date it will not have the proper viscosity and can cause a loud rearend aswell. This can often be heard as bearing and gear noise.

[minitubbed_82lx]

So I jacked the car up and all the bolt were tight except the driveshaft and the upper control arms were they meet the spherical bushing. I tightened these damn things as stated and they are loose again. The noise is gone and the car even drives better. I think that I am going to get lock washers and some lock tight blue.