Rhelbig

I have a 2011 with 43K miles. I have a rattle underneath when the RPMs are around 6K. Performance is great, no problems when accelerating. Had what seems like the same problem about 2 years ago. Dealer had it for 1.5 weeks, so not much confidence as what they did to solve the problem. I'm experiencing the same noise, and the car is older than 5 years. Anyone have history on this?

Much appreciated,


Ray

Rhelbig

Sorry, that's 600 RPM

Ray

stingray71

Does it make the noise when idling - car is not moving?

Rhelbig

Yep. Anything over about 700 RPMs or moving and it goes away

Kenny94945

Jack the car up.
Take a rubber hammer to the exhaust first, then everything else.
Rattles can be tricky, don't rule out that the rattle is coming from the front or the interior.
Good hunting.

doubleD

Check the Torque tube assembly. Mine behaved the same way. Replaced the torque tube and no noise.

gr86ss

Sometimes the intermediate pipe rear hanger springs will rattle because the exhaust isn't putting tension on the spring(s). Check there. If that's where you're noise is coming from, pull the hangers out and spray them with plasti-dip. The rubberized coating will dampen the metal to metal rattling that you're experiencing

cleif2000

Agree. Same problem with mine at idle, sounded like a can of marbles. Sound would go away under load. Car ran fine. Noise will get louder with time. Front bearings in Toque Tube bad. Good Luck.

Rhelbig

That's, the torque tube. Dealer quoting $2400. Car is 5.5 years old, 43K miles. Last year it was the alternator at 37 K miles, $1100. I called GM looking for some help, they told me to **** off. Let's just say my love affair with GM is strained.

Andy1982

I had/have the same issue on my 2011 GS with 40K miles. We replaced the rear two bearings as rust colored dust (?) could be seen and felt at the rearward bearing. Within 2500 miles, the genuine GM replacement bearings are now doing the same thing as the originals. ( A repair that was $1500. I am not a happy camper!) We'll try ANOTHER set of bearings, and also change out the front bearing too even though it is smooth feeling and no rust/dust could be detected. Did you replace the stationary, aluminum tube that houses the rotating shaft that I would call the true drive shaft, since it transfers the engine's rotation to the rear transmission assembly? Logically speaking, I can't see how something that doesn't rotate or move at all could cause a noise that goes away when the RPM is increased. I would appreciate any information that you could share with me on this problem.

In reading other posts on the subject, it appears that quite a few other folks have experienced the same problem. I'm wondering if and how they truly fixed the problem. And if the growling noise returned after 4 or 5 thousand miles or not. (Or were they frustrated enough and sold the car out of spite? I am rapidly approaching that point, as much as I hate to!) HELP!!!

And by the way, how many miles have you put on the repair job since it was completed? Any hint of returning noise or growling?

Rhelbig

Torque tube is done. Took the Ft. Myers dealer 2 weeks, and a door scuff on my door, which they have take care of. Since GM told me to **** off, I'm looking for a good mechanic in the Ft. Myers/Cape Coral area, if anyone knows one.
Thanks all for your input,
Ray

jrose7004

Maybe the cat back is loose?

Boomer111

I experienced something similar and a little lithium grease on the exhaust spring hangers solved it.

good luck

Rhelbig

Turns out it was the second time the torque tube was replaced. First time was under warranty at about 20,000 miles. Hope this replacement lasts longer.