[TatsuSensei]

Originally Posted by cryssm

V6 and I4 models equipped with the manual transmission have limited-slip differentials, as well.

My RS V6 A8 leaves dual black marks when I light up the tires......

[Justice]

I'm about to hit 15k miles on my 2SS and it's had the groan for at least the last 7k. I've changed the fluid once myself with the recommend fluid and it went away for a few weeks, but came back. I've been trying to avoid the dealership, but I think I need to get it in so they have this issue on record. I love my car to death, but the first years seems to have a lot of issues. I don't know if the "first year" build problems saying is true, but I damn sure will think twice before rushing into a first year car again. This will be my 3rd trip to the dealership (Oil pan thing and trans lines), and I think I'm starting to feel the issue with my converter A8 people have been mentioning..../sigh...

[Meteorma]

here

[robbie52]

I have the groan, which is really noticeable with a cold start, and the dealer did not see an issue. They did state that I could leave the car overnight to see if they could duplicate the issue.

[tumbla.jr]

My diff was just replaced at 24K

[Chevy71]

My car has this issue as well, I've had it to two dealerships and neither will do anything. The second dealer (Day Chevrolet in Monroeville) told me they would have a GM engineer come to the shop to look at the list of issues I was having. They kept the car three days and gave it back to me without fixing anything. Said everything was normal. They blamed the diff groan on my tires (it has done that since the day I got it) and dismissed everything else. Winter has came since then and the car hasn't been moved. I have around 12,000 miles on it.

[Mad Mike]

Well, looks like I need to change my answer on the poll. I had the diff replaced just after 10k miles. Now I'm at 14,500 and I'm starting to hear the rubbing noise.

[suzook]

Originally Posted by Techn9cian805

why are dealerships refusing a simple fluid flush?

3 dealers by me refused. They said GM won't authorize it.

[Tim Adams]

Originally Posted by suzook

3 dealers by me refused. They said GM won't authorize it.

I take mine in tomorrow for this plus the recall for the trans cooler lines. I know we want GM to just fix it, or change the fluid, but if I have to pay them I will. The car is not leaving the dealer until the damn fluid is changed.

[Tim Adams]

Dealer could not replicate mine. I am paying them to change the fluid.

[stook2001]

Originally Posted by Tim Adams

Dealer could not replicate mine. I am paying them to change the fluid.

You're more then welcome to do what you like but from what I have read the OEM fluid swap doesnt appear to be a permanent fix. Once you are paying for the swap you'd might as well try installing higher quality gear oil. Not sure the dealer will do it for you but I suppose you could ask.

If all anyone ever does is keep trying the GM gear oil we're never going to find out if that is the underlying issue. The fact that it fixes the issue for a little while tells you that it might very well be the gear oil. Or maybe not... but if we put our collective efforts together, we might make some progress on the issue.

[Car Junkie]

I noticed the groan at about 3k miles. Have 4K now. Time for a dealer visit.
However I will say the car does Rock and its very fast. The Mag Ride is killer.
The 8 Speed auto is fantastic.

[jls]

I had the fluid changed February 1 and the groan is returning.

[TDX2000]

I figured it's time to share my groan story with everyone. I first had the groan start about a month after I bought the car. I took it to one dealer and they tried to tell me it was the brakes. I didn't waste time trying to argue with them. I just took it to another dealer who has been great. When I took it to them I had already called GM support and opened a case with them. I gave the case number to the service guy and they did the rear diff fluid change and figure eights. That worked for about a month (maybe). I took it back in and they spoke with GM. GM authorized a rear diff carrier replace. They replaced the carrier the end of March. I have not had the groan until about 2 weeks ago. I took it back to the dealership. They heard the grown and had a GM tech come look at the car. He told them it was normal. The dealership asked me to come pickup my car. At this point I called GM and opened another case with them as if this was a "normal" behavior, they would not have a SB on it nor would they have replaced the rear diff carrier. I should hear back on this case from GM tomorrow. In total the car has been seen and documented for this issue 4 times now. I had to also take the car in for an issue with some sort of "vibration or chatter" when the car is warm and under slight acceleration. The dealership flushed the transmission fluid and told me to put 200 miles on the car. I have since put about 500 miles on the car and the chatter has not returned. At this point I am very concerned about the rear diff and transmission issues I have been having. I love the car but I am not willing to except this as normal operational behavior. I would not like to lemon law it, so I hope GM will step up and figure out what is causing this and fix it. My advice to anyone going through this BS is to find a good dealership and don't get mad at them. They usually can only do what GM authorizes. So put the pressure on GM. So far this approach has worked well for me.