Clunk noise when shifting from P to D/R to D

[khpappas]

Hey guys, got an 06 2.8 and when I shift from into R or D I notice a clunk in the drivetrain. Happens when its cold or warm. Sounds to me like a trans mount or something in the rear end/suspension, driveshaft possibly. Taking the car in monday for the diff warranty. Any ideas?

[SvB4EvA]

What is the car idling at when in N and then when put in D?

[caddyshack33]

I know there was a TSB out for something similar in earlier year models. Give me a second and I'll see if I can find it. I remember I came across it because I wanted to find the fix for the drivetrain noise with the MANUAL. Damn cadillac put out at TSB saying that the manual sound was NORMAL!

[caddyshack33]

OK, do NOT give them the following TSB. It's the same BS they had on the manual transmission (that this "clunk" noise is "normal" blah blah blah -- except that this is the only car I've ever had this "clunk" noise with). The actual TSB Cadillac put out stated that "no repairs should be attempted." You can tell them about the noise and maybe you'll get lucky and they'll fix it anyway. I've read in some other posts that replacing the rear bushings help, http://www.cadillacforums.com/forums...7-clunk-2.html (Clunk...)

The summary for the TSB is as follows:

06/01/2006 DRIVELINE CLUNK NOISE WHEN SHIFTING BETWEEN PARK AND DRIVE, PARK AND REVERSE OR DRIVE AND REVERSE - REVISED

[CTS Orlando]

Had the same problem. Its a bushing. Had it replaced under warranty. $.50 part, $450 labor. The geniuses at GM thought it would be a good idea to put a flimsy piece of rubber between a drive shaft carrying 255hp and the differential. Go figure.

[Cadillacfilter1]

I am having the same probleme. I got an 03 with 187000 kms. Could it be the tranny going bad or differnital?

[dup's Cadi]

There are two of those "donuts" on the drive shaft. They are held on by 6 bolts. I have had the the ones on the front come loose and stretch a few bolts and even break. The worst part was the output shaft on the trans got messed up to. It stretched one of the holes that those bolts go through. I had to change my trans anyway, so that fixed that problem. I was told by my dealer that you can't by them separately. If you can, anyone have a part number?

[Sammy Z]

Maybe a GM mechanic could help here. I did a search for Universal Joints and there is more info on the CTS V forum. Seems those rubber donuts fall apart due to wear. Try calling a Drive shaft company to see if they have a part.