Car Troubles

I love my Chevy Cobalt, I bought it new 6 years ago and its been good to me.

I had new winter tires put on and balanced, new rear springs and shocks put on by my local mechanic who is usually good but upon leaving I noticed two things, one I now had a metal on metal clunk over bumps on the right rear side and a shake in the tires/car at a certain speed or higher, took it back and he said tires are balanced and the clunk was nothing to worry about but if your like me that noise drives your OCD crazy.

Not happy I decide to take it to the Chevy dealership where I bought it and explain what I had done and what was going on thinking the trained mechanics should have it in and out in no time.

Wrong, they could not find what was causing the clunk, the Service guy asked if I want to make another appointment for them to tear my rear end apart because they dont think its the shocks or suspension and spend more $$$ to do a road force balance test on the tires and rims when I thought thats what they were going to do in the first place.

I'm ready to flip out at this point and said no just give me the bill and let me get out of here.

So $211 and 4 hours later my car is still not fixed.

I just needed to vent about it, thanks for anyone who reads and understands how I'm feeling at the moment.

The irony lies with your username attached to this post.

Hope they get it figured out.

The shaking at higher speeds is a concern that certainly needs sorting out. I am not sure what led you to replace the springs along with shocks but the clunking might be some issue with aftermarket parts or their installation. Maybe a worrisome issue or maybe not.

IMO your local mechanic should be the one to help resolve these issues which were introduced by the repair or at least give a better explanation, especially with the new vibration. Simply saying the tires are balanced is not good enough. Most often after suspension work the vehicle will need a new alignment.

this might be of use:
http://www.yourcobalt.com/forums/suspension-wheels-brakes-tires/48233-rear-end-clunk.html

Some tires, winter "studded" tires for example, will make some extra noise, as in a hum, but vibrations are an issue. They either aren't balanced correctly, or there are suspension issues. The mechanic should be willing to resolve these at no charge. If not, contact the BBB, and move on from his service. That's really all you can do unless you're willing to lawyer up. I'm not sure that option would be cost efficient .
I'd definitely look into the quality of parts that were put in place of the factory ones. When it comes to suspension, the only aftermarket brand worth using is MOOG. Past that, stick with dealer parts. Good luck.

Also, I'll add that my 1999 f-150 produced a rattle from the front wheels for months. Especially over small bumps. Turns out there was wear on the brake pad hardware (retaining clips) causing them to rattle. Slightly press the brake before bumps to determine if it is a brake issue. If the noise isn't there while pressing the brakes, it is a brake issue. If it persists, definitely suspension/stability linkage. Again, good luck.

WalterK said:

this might be of use:
http://www.yourcobalt.com/forums/suspension-wheels-brakes-tires/48233-rear-end-clunk.html

Click to expand...

Bolts were torqued and retorqed, swapped out you name it, didn't fix it.

MichaelRB88 said:

Some tires, winter "studded" tires for example, will make some extra noise, as in a hum, but vibrations are an issue. They either aren't balanced correctly, or there are suspension issues. The mechanic should be willing to resolve these at no charge. If not, contact the BBB, and move on from his service. That's really all you can do unless you're willing to lawyer up. I'm not sure that option would be cost efficient .
I'd definitely look into the quality of parts that were put in place of the factory ones. When it comes to suspension, the only aftermarket brand worth using is MOOG. Past that, stick with dealer parts. Good luck.

Also, I'll add that my 1999 f-150 produced a rattle from the front wheels for months. Especially over small bumps. Turns out there was wear on the brake pad hardware (retaining clips) causing them to rattle. Slightly press the brake before bumps to determine if it is a brake issue. If the noise isn't there while pressing the brakes, it is a brake issue. If it persists, definitely suspension/stability linkage. Again, good luck.

Click to expand...

Springs were MOOG, bought all the parts myself.

It only makes the noise under heavy road imperfections/bumps, at lower speeds. To me it sounds like when the coil spring compresses and rebounds it's making contract with itself or something else but it can't be because I spent all afternoon myself ripping the trunk apart, the rear seat apart, borrowed a buddies floor jack and looked underneath with a flashlight for an hour looking for something broke, rubbing or loose and can't find a thing wrong that would be causing the "ting ting" clunking noise.

Does that Cobalt have a rear sway bar? If so, the end link could be broken. They go from the end of the sway bar onto the shocks so over bumps this can clunk pretty badly.

Dalejr said:

Springs were MOOG, bought all the parts myself.

It only makes the noise under heavy road imperfections/bumps, at lower speeds. To me it sounds like when the coil spring compresses and rebounds it's making contract with itself or something else but it can't be because I spent all afternoon myself ripping the trunk apart, the rear seat apart, borrowed a buddies floor jack and looked underneath with a flashlight for an hour looking for something broke, rubbing or loose and can't find a thing wrong that would be causing the "ting ting" clunking noise.

Click to expand...

It could be the sway bar links as mentioned in another reply. It could also be as simple as a rubber bushing being left out in the installation process, leaving metal contacting metal somewhere it shouldn't. Hard to diagnose without being in person. I still think the mechanic should be willing to track this down. Which could present a problem if you've torn into it yourself. I hope you get it straightened out. Keep us posted. I'd like to know just out of curiosity.

Another thing not mentioned yet, but a bit out-there concerns the breaks. Some guys swap the rear drum breaks for disk breaks. I've once had break pads replaced and the mechanic neglected to install the spring clips that keep the pads from shaking. It produced clunking sound similar to what you described that disappeared when the breaks were applied.

What rear shocks did you use? Some require the old bump stops to be reused, while others come with new bump stops. Missing or worn out bump stops would definitely cause a clunk.

make doubly sure the tires are inflated properly, dont assume anything. cold weather can be a culprit in strange sounds, metal contracts and tolerances change. if the shocks are new they might need to be broken in, some new parts need it some dont. is the clunk loud or fairly soft? it could be the new shocks have a different compression weight.

Any news?

tetraodon said:

make doubly sure the tires are inflated properly, dont assume anything. cold weather can be a culprit in strange sounds, metal contracts and tolerances change. if the shocks are new they might need to be broken in, some new parts need it some dont. is the clunk loud or fairly soft? it could be the new shocks have a different compression weight.

Click to expand...

Quite loud and not soft.

WalterK said:

Any news?

Click to expand...

Noise is getting worse in my opinion. I am taking it back to the mechanic who did the work to my car when I can get time off, which I hope is soon because I have OCD and it's driving me nuts.

I still have a funny feeling it could be the bump stops, I've even seen them installed upside down which caused a good noise.