Gh0st

iTrader: (3)

2008 RCSB with 22k miles on it. Bought the truck used a few months ago with 18k on it and have been having this issue since.

What happens and it's not EVERY time I drive the truck, but quite often, when I come to a stop, the truck will make a clunk noise and then it will lurch forward. It feels like the truck momentarily is popping back in to gear. It's not immediately when I stop, but it'll be about 5-10 seconds after I've stopped the truck.

I also have the notorious kinda crappy 1-2 shift that is a little rough. Truck is bone stock and all fluids are fine.

Gh0st

iTrader: (3)

Here's another person with the same issue:

http://www.fullsizechevy.com/showthr...orward-Jolting

I'm going to take it to the dealer to see what they say. Please let me know if any of you have had this issue.

Whippled2dr

iTrader: (4)

I have the same issue with my 2008 4.8L RCSB 2wd WT. I have about 12K miles on it and its done it since new. I've just been lazy to take it to the dealer to have it checked out. I think it might be torque converter related.

MPFD

iTrader: (5)

The problem is in the driveshaft yoke. GM makes a special lube for this problem, but a good Molly lube will work fine. GM also made a nickle plated slip yoke to eliminate the issue but it cost to much for this cheap ***. Pull it out and lube the inside of the slip yoke on the splines with a white lithium grease, it will stop.

fun4me

Why do it yourself. The truck has a 100,000 mile powertrain warranty. There is a TSB for this problem. The dealer will first try to lube the driveshaft yoke. If that doesn't fix the problem, it won't, then they are to replace the driveshaft slip yoke. If that doesn't fix it, it won't, then they remove the trans, disassemble it & replace the output shaft.

MPFD

iTrader: (5)

I lubed mine once with the GM lube when I was working at a GMC Pontiac dealership in 2003. I didn't need to lube it again until I replaced my transmission at 168,000 with an FLT around April this year... fwiw

budhayes3

iTrader: (19)

They're still having this problem on the 08's? BTW, I got the nickel plated slip yoke and installed it with new u-joints when I did my trans swap and the noise seems to be gone now. I have gotten a new clunk during the 1-2 shifts at times, but I think that's coming from the rear. My G-80 recently dumped, as now when I launch I have a one wheel peel, and when I put it on the lift and turn one wheel forward, the other one goes the other direction. Front diff is shot too...all this with my mild 5.3. Nice new trans, and the rest of the driveline needs an overhaul (except the t-case which looked brand new when I cracked it open to upgrade to the redesigned pump clip).

Gh0st

iTrader: (3)

Thanks for the help guys. I will work with a local dealership. I just moved to Minneapolis so I'll have to find a good place to go that is reputable.