Pretty bad problem with 06 Denali when coming to a stop

[imperil]

I am hoping somebody here can point me in the right direction.. or ANY direction as I've had a pretty massive run around from GM.

I have had my truck 2 years now, an 06 Envoy Denali, and it has had a problem since it was only a few months old but it is getting much worse. Basically when slowing down and coming to a stop at a light or stop sign, the truck will be fully stopped and then all of a sudden you hear a clunk noise and it feels like someone has hit you from behind (is this the transmission shifting down lagged or something?). This used to only happen occasionally, a few times a month, but now it has started happening a few times every day. Anytime I bring it to the dealership they just lie to me and tell me they took it out and couldn't find anything wrong. Has anybody else had this problem?

I am so upset about this if I can't get it solved I am going to eat 11 grand of negative equity on the lease to get rid of it and never look at a GM vehicle again. Thanks.

[Exit32]

You've described a common ailment, imperil. There are many theories regarding this strange behavior. Check out this thread for more information:

http://forums.trailvoy.com/showthread.php?t=7177

Please let us know if have any other ideas about the cause of these "mystery bumps".

[Exit32]

Also, please check out this discussion on recent Technical Service Bulletins:

http://forums.trailvoy.com/showthread.php?t=36291

You might want to mention TSB 07-04-17-001 (06/06/2007 Drivetrain - Rear End Bump/Thump on Braking) to your dealer.

Please let us know what happens!

[Envoy Fan]

Insist on going with the tech when he drives it so you can show them the problem. While aggravating, not worth the 11K hit. Hang in there.

Curious, are you 2WD or 4WD?

[imperil]

4WD, Canada :) Looks like I don't have time to take it in for a week or two, but will be going shortly to try and get this worked out.

[Envoy Fan]

One of the little "games" I play with mine when it is just first starting up and we have to come to a stop is to stop with more distance than normal from the vehicle in front of me. Then count 10 seconds release foot brakes and inch forward a few feet. Then maybe do it again. Seems to lessen the bump occurances. :crazy:

Maybe you could have a "serious" talk with the service manager. Convince him to keep it and he drive it for a couple of days. Hopefully they will work with your concerns and let you have a loaner in the meantime.

[PROSPHOTO]

User CP->"edit profile"...please add all of your vehicle information in your profile :yes:

As for your concern...there is only one bulletin that addressis this concern on the '06 MY TrailVoys:

Some customers may comment of a bump or thump noise heard from the rear suspension or felt in the floor. The information below will affect vehicles with G67 Automatic Level Control rear suspension. This noise will typically occur between traffic lights on rapid stops. This noise is due to a combination of the rear electronic suspension attempting to level the vehicle and the driveline becoming unbound after these rapid stops.

[jhgw]

At the dealer today (8/25), there is a new TSB out with a fix. (If your under warranty). A new seal with a boot so the grease doesn't dry up so quickly.