saadooness

Hi All,

Does anyone have an idea why my C7 makes a weird scratching sound underneath my when i down shift from 3rd to second? its heard when rev matching is enabled and the gear needs to be in the high rev range. My C7 is barely a week old and im freaking out. Would this be a problem with my clutch? i drive hard but not hard enough to burn my clutch.

Thanks for your help.

travisnd

Hard to help w/o video, but there have been issues with the belt tensioners making excessive noise as well as defective bearings in the torque tube assembly. If it were the torque tube you should hear it clunking/clanking at idle.

saadooness

If iI shift into a gear at idle and go back to neutral then release clutch I hear a clunk sound. Just pressing and releasing the clutch in idle produces no sounds.

stevebz06

I wonder if it could have something to do with the dual-mass flywheel?

Seapar

Hope it is ok. Just wondering if it a week old then perhaps you should adhere to break in recommendations and drive it less "hard". Just saying.i would still take it to where you can get warranty work done, however, sooner than later.

saadooness

I've got 800 miles on it already I kept below 4k rpm for the first 500.

saadooness

UPDATE: visited my local service center this morning and they couldnt find any issues with the clutch or tranny. I took the mechanic for a test run and had to push the car a little hard for the clicking sound to be heard when downshifting. He said that the sound is from the tranny and most likely normal when pushing the car hard. They are gonna check with GM and give me a call back within the next few days.

NoOne

You will hear some mechanical/engagement sounds but they are pretty muffled on the C7. I drove mine with the center console off when I installed my MGW and there is a sound similar to what you describe.

That whole system makes a ton of noise, its just a matter of how much you hear.

JerryU

Interesting thought. Lots of parts, friction surfaces, springs and a plate with tabs contacting the stops that could make noise.
Found and interesting PDF about it, why it is used especially on high hp engines.

luk_fail_diag_zms_de_en.pdf

Chevy Cust Svc

Sorry to hear about your noise situation. I realize how concerning that would be. Keep us posted on the results of your dealer's research. If necessary, I can contact their designated Customer Experience Manager if you have any additional questions. We'll look forward to your updates .

William R.
Chevrolet Customer Care

saadooness

Thanks William, it would be great if you could help get an answer from GM regarding this sound. My dealer hasnt been able to get a response from GM as of today.

Chevy Cust Svc

You're very welcome,

I'd be happy to assist if you message me privately. If you do so, please include your name, address, VIN, mileage, and dealer in case an official GM is created on your behalf. Let me know if that's fine with you, or if you have any additional questions.

William R.
Chevrolet Customer Care