Loud thumping from the rear.

[Sik]

So for the past few weeks there has been a loud thumping noise coming from the rear of my coupe. The sound gradually speeds up as my car speeds up. When I get over 45sh i cant hear it anymore(probably because it gets drowned out). I dont have any bald spots on my tires, I have also just replaced my brake shoes and wheel cylinders because they needed to be done anyway. I thought at first that my wheels might be hitting the drum because my bolts were messed up. I still cant find the issue, does anyone know where it might be coming from. Its hard to distinguish what side its coming from since i think its coming from the drivers side and my passenger thinks its coming from their side.

 

[sm3570]

No idea, but from reading other posts I'd say check your u-joints and maybe the rear end (the car's, not yours). Hopefully someone will chime in with better advise.

 

[Sik]

No idea, but from reading other posts I'd say check your u-joints and maybe the rear end (the car's, not yours). Hopefully someone will chime in with better advise.

ok ill check my u-joints tomorrow . I thought about my rear end, and i really hope its not that!

 

[sm3570]

No kidding, that can be an expensive repair! It sounds like something rotational because the thumping speeds up as you speed up, right? Is there a vibration that goes along with it?

 

[Sik]

Well there wasnt when it first started, but i think I may be able to feel the thumps a little bit, but its not vibrating.

 

[canadian_red_maple_leaf]

Well there wasnt when it first started, but i think I may be able to feel the thumps a little bit, but its not vibrating.

i had the same problem once and it was the rear u-joint that was shot. i had the u-joint replaced and rebalanced. no problems from then on and that was 3 years ago.

abudi

 

[c9zx]

It could be a broken or separated cord in the tire. If possible switch rear tires to the front to see if the thump moves with the tires. 30 minutes time, 0 cost. Chuck

 

[Tnfastbk]

Have you checked for one of these in the trunk?

 

[72HCODE]

does the thumping stop if you lightly apply the brakes?

does the thumping stop when you come off throttle and just coast?

have the lug nuts loosened?

 

[1971mach1]

It does sound like loose lug nuts.

OP: You said "bolts were messed up", what bolts were those?

 

[Sik]

It does sound like loose lug nuts.

OP: You said "bolts were messed up", what bolts were those?

It was the lug nut studs, sorry i should have been more specific. I replaced those and my lug nuts. I thought it was those at first too.

I went to a ghetto tire store to get my new tires and they didnt tighten the lug nuts enough which caused them to destroy the threads on the studs.

and to 72HCODE

I can hear the thumping constantly, it dosnt matter if im applying the brakes or if I am gassing it. All the lug nuts are tight too.

 

[marks73]

Time to replace the u-joints. If that doesnt do it. Drain the rearend lube and look for metal.

 

[Sik]

The U-joints make alot of sense. On monday ill get around to checking them out and ill update you guys!

 

[trumanbonner]

Hi sik have you had a check on the U joint because em also facing the same problem as you are so pls update fast so then i will also try the same.

____________________

Airport Car Parking

 

[FasTnNefariouS]

Did you find the problem? If not, could it be loose shocks, swaybar or traction bars if you got em? Damaged bushings to any of these parts? This would also produce a thumping/clunking noise.

 

[coilwire]

Can you get your hands on a set of chassis ears. This tool works wonders for finding noises coming from under the car.

Jim

 

[Tnfastbk]

Wife/girlfriend locked in the trunk?

 

[marks73]

God I was thinking the same thing. That's when you know they love ya!

 

[Sik]

sorry I took awhile to post a reply but i think I may have found the problem. This months issue of mustangs monthly has an article on replacing leaky axle seals and gaskets. I have been looking into the problem and it has alot of the same issues such as liquid coming from my right rear tire. At first I thought it was brake fluid leaking, but my brake fluid was full. So tommorow after work I am going to tear back into it and see if that is the problem.