Suspension banging

[ertoys]

I have something banging in the back of my car when I go over bumps in a stright line and around corners.

I have replaced EVERYTHING suspension wise front and rear everthing is new and torqued down correctly.

I have removed the spare...trunk is empty.

I jacked up the car and banged on the fuel tank, it seems solid on both sides.

I had someone help me push down hard...(bounce) the rear of the car, no noise.

I am going crazy trying to figure this out?????????????????:crying:

Any suggestions?

[CAMAROBOY69]

Are all the U-bolts tight? Driveshaft? Shocks? The brackets for the leafs? Check all that stuff. Jack the body up next time and not the rear axle that way you take the weight off the suspension. THen try to see if anything has marks on it or is moving around.

[Rick Dorion]

Exhaust? Mine started hitting in a similiar fashion after my hotchkis leafs went in - right where the tailpipes start to go over the axle.

[68BNUT]

I had something banging in the back of my car. I had a shock that was binding up and making the metal floor flex back and forth, eventually it ripped the trunk apart at the seems. just a thought or you could stop carrying midgets around in the trunk!

[CarlC]

Also check the face of the rear frame rails just above the axle tube. If you are using U-bolts there is potential for the bolt to hit the rail under hard bumps.

[ertoys]

Everything is tight and I took the advice to jack up the rear by the rails.

I still could not see anything, baged on fuel tank it is in there solid springs are tight I could not see any rub marks on the upper frem rails or the rearend.

I took it to a shop and I will see what they come up with.:hmm:

Is it possible for the washers on top of the shocks (in the trunk) to be hitting the trunk floor? the reason I ask is there is only about an 1/8" between the washer and trunk floor.

On the trunk inside I slid the rubber snubber on the shock shaft, then the washer then the nut.

Did I do something wrong?

[CAMAROBOY69]

I took it to a shop and I will see what they come up with.:hmm:

Any results from the shop?

[ertoys]

No unfortunately they could not find it.

I am taking it to my friend wwho is a mechanic tomorrow, hopefully we can figure it out.

Thanks for asking,
Ed

[CAMAROBOY69]

Try jacking up the rear diff and put the car in neutral. Then turn the driveshaft by hand to see if there is something wrong inside the rear diff. Just another thought. I hope the shop didnt charge you if they didnt find anything. :pat:
Or take the shocks back out and check them 100% to see if there are any visible marks. Noises drive me insane so I know what your going thru.
EDIT: Hmm what else could it be. Body twisting, trunk lid banging? I know my trunk makes noise once in a while. Or my rear spoiler will make noise if it starts coming loose.

[Supercharged 86]

I didn't read through every post, but if you changed the brakes in the rear, check to see if they're hitting the frame or close to it when the suspension is loaded. Somebody welded disc brake brackets pretty much straight up and when I installed parking brake calipers the mechanism hit the frame once it was on the ground. Not cool!

[paul67]

does the bang happen when you go on to the bump or when you go off the bump ?
paul67

[zbugger]

I had a broken shock do pretty much exactly that. It was a loud clunk too. only difference is I knew exactly how and where I broke the damn thing. And then I went and did 130 mph on it. It's fixed now though. Pushing down on the car I could barely reproduce the sound. Oh, and the shock was all oily on the outside after that too.

My buddy's Honda was doing that from the front end a while back. He had aftermarket swaybars installed, and they didn't tighten down the endlinks properly. At least that one was an easy fix. I hope you find your problem.

[MrQuick]

couple questions:
Is it lowered ? If so, how?
Is it jacked up? If so, how?
Your shocks can be bottoming out or over extending, depending on which way you went.That makes a loud & violent bump sensation.
Another thing is to check the bump stops.If you are real close to them trimming will be a fix. Try this, get some white grease and apply it to the rubber bumpers, 1 over the rear end snout and 2 over the rear frame rails. Drive it around and get it to bump, then check the rear end for signs of white grease. let us know what you find.

[yody]

check your rear end pinion yoke, they can hit the mufflers or the tranny tunnel. jack the rearend up by the pumpkin so the suspension is compressed when you look under

[qwik1320]

Where does your exhaust exit? My right rear tailpipe was hitting the bottom flange of the quarter panel when I'd hit a bump. It wouldn't do it all the time... The tail pipe wouldn't move by hand but I finally noticed a little "scuff" mark on the pipe and trimmed about 1/8" off the QP. No more banging.

[streetk14]

This might sound stupid, but what about the rear window glass? Mine came loose from the body flexing during hard cornering. It was rattling at times and would "clunk" over bumps. It drove me crazy until I resealed it. Just a thought. If it is something in the suspension, find someone with a set of "chassis ears". They are sometimes very helpful in finding the source of suspension noise. Good luck,
Andy

[ertoys]

These are all great suggestions, thank you.

I wont be able to check any of these things out until like Thursday.

I will let you guys know what I find if anything.

I am just amazed at this whole thing because there is only so much back there.

[chicane67]

Shackles might be hitting the rear frame rail....if:

~The rear springs have been replaced with aftermarket springs with the addition of...
~The rear shackles being replaced with aftermarket shackles.

The shackle lengths from manufacturer to manufacturer are different and this may be something to look into. Its a common problem when using multiple product lines that were not designed and/or engineered together. Certain 'packages' are packages for a reason...

[ertoys]

This might sound stupid, but what about the rear window glass? Mine came loose from the body flexing during hard cornering. It was rattling at times and would "clunk" over bumps. It drove me crazy until I resealed it. Just a thought. If it is something in the suspension, find someone with a set of "chassis ears". They are sometimes very helpful in finding the source of suspension noise. Good luck,
Andy

Not stupid at all, I checked it and you are the lucky winner! It is the back glass. I tapped it from the inside and man did it shake and rattle.

I will go get it fixed tomorrow. Man this is great, I have been plagued by this noise for two weeks! :bananna2:

[CAMAROBOY69]

Great find Andy!!! I would have never guessed that. Now I will keep that in mind if I ever hear strange noises in my rear and cant find them. Wait that didnt sound right. :fart: :scared:
Congrats on finding the problem.

[Rick Dorion]

Gotta love those obscure problems. And this site for the knowledge!

[zman1969]

I know this is a different car but I built a 66 Nova SS that had a mystery clunk like yours - turned out it was my right front spring mount - had prev repair on it in past that looked bad - I torched one off a parts car - it had like 12 spot welds holding it in. when I got to remove it - I cut like 3 spot welds off it and it hit the ground! it was definetly not in there right. after welding it in right mystery noise was gone! - check the front spring mounts may be loose? loved the ride after i fixed it - drove me batty too! good luck and hope it helps

[ertoys]

Thanks for the replies everyone, the noise has been isolated and fixed!

A special thanks to streetk14 for the tip to check the back glass.

I had a company come out yesterday and pull the back glass and reseal it....no more bang!

I drove it to work yesterday and it was so nice not to hear that clumk anymore.:camaro: