Drive Train Harmonics
 

So,

After a few hundred miles on my 2SS I started noticing some drive train noise. At a point when I was in country, (I work in Brazil) I decided to take it to the dealer I bought the car from to have it checked.

This noise was in most any gear from 1200 to 3500-4000 rpm under mild to moderately heavy loading. Above 4000 it either was covered by the exhaust (GMPP Offroad Axle Back) or it was spinning so fast as to not be noticable.

The service manager assigned his "Tranny Specialist" to it and we went for a ride. He didn't hear anything, so I pulled over and let him drive.... Still nada...I heard it the whole time... We went back to the dealership, and he did some checks, no metal in the tranny fluid, didn't find anything else....so they wrote it up and sent me on down the road.... As I'm leaving the dealership, I still hear the noise...quite loudly... as I had when we were driving around...

I got back from my next trip to Brazil, and a little over a week ago, I took it to a dealership where the service manager is a long time family friend. Service manager took a ride with me and he immediately picked up on the noise and you could almost see the gears in his head grinding as he was trying to determine what could make that noise based on driving conditions... He talked about a number of things... and said he would do some research... I kept the car with an appointment to bring it back in Monday the 29th of March.

I drove it in Monday morning and he said GM had sent him a page long list of things to check, and to call the engineering rep when he had the car in hand.

31-Mar-10 Update... The service manager just called me and said that a GM engineering rep was on the way. Will be here today...Apparently there is some problem of this type in very limited numbers, and they are trying to get as much info as possible to resolve it... Kudo's to GM and Chevrolet for working so hard to determine a limited scope problem...and most especially to the dealer service manager...

He also asked me what brand of shifter I had in my car, and what type of exhaust it was.... He loves the shifter feel and throw, and likes the exhaust note...

MGW, short throw shifter, drive train noise was present prior to the installation.
GMPP Offroad Axle Back,
All other Mods to date have been cosmetic in nature...

I wanted to wait until I had 8-10 thousand miles on it just in case something came up, as it did with the drive train noise. There is a Pro-Charger in my future, but waiting for any issues to be resolved...

Updates to follow...

The MGW shifter amplifies the sound of the gears as they mesh while cruising and you will hear more of the whine noise that was being muffled by the factory shifter. If you put your hand on the shifter knob you can change this pitch of the sounds. This is more noticeable with the "race knob". Great shifter, but it is not as quiet as stock.

-Mark.

True, but as mentioned, the noise was present prior to installing the MGW, and this is noise under loading, not cruising...

This noise has nothing to do with the shifter... there are a few other similar cases with the camaro, thats why GM is sending an Engineer down to determine what is causing it and how to fix it...

Im having the same noise in mine but reduced drastically with mobil 1 ATF tranny fluid! Still slightly there tho. Keep us posted on ur results!!!