Clunk when accel from a stop fixed.

[89vette]

I had this nagging clunk/thunk sound from the rear of the vehicle every time I starting moving from a stopped condition. Dealer said it was a "normal condition". I brought it back and told them to check the slip yoke coming out of the back of the transfer case. They said everything was normal. I got pissed and left.

I bought some good adhesive grease and greased the splines the yoke slides on. Put the driveshaft back in and guess what? No more noise at all. In fact whan I removed the slip yoke, there was very little lubrication on the slpines.

The only thing I am concerned over is the grease dissolving and mixing with the transfer case oil. That is why I opted for the adhesive grease which tends to stay where its placed.

Jason

03 Sunset H2!
89 Vette
02 Escalade

[89vette]

I had this nagging clunk/thunk sound from the rear of the vehicle every time I starting moving from a stopped condition. Dealer said it was a "normal condition". I brought it back and told them to check the slip yoke coming out of the back of the transfer case. They said everything was normal. I got pissed and left.

I bought some good adhesive grease and greased the splines the yoke slides on. Put the driveshaft back in and guess what? No more noise at all. In fact whan I removed the slip yoke, there was very little lubrication on the slpines.

The only thing I am concerned over is the grease dissolving and mixing with the transfer case oil. That is why I opted for the adhesive grease which tends to stay where its placed.

Jason

03 Sunset H2!
89 Vette
02 Escalade

[Zing]

I may have the same issue. Lately I thought I had something sliding around in the back when I didn't.

What is a slip yoke? To grease this sounds like I have to remove the drive shaft?

[89vette]

Yes you do have to remove the driveshaft. The slip yoke is the part on the drivesfaft that slides into the rear of the transfer case. This issue is ver common with all GM 4 x 4's. A buddy of mine has an 04 and his does the same exact thing. My Silverado did it too and they installed an updated slip yoke. No such fix for the H2. Dealer said it was normal. About the only thing that was normal was my royal dealer screwing.

03 Sunset H2!
89 Vette
02 Escalade

[Zing]

Thanks. Next time I'm at my dealer (Paramus, NJ) I'll mention this and see if they'll be helpful.

[DRTYFN]

Had the same thing happen on my '97 Tahoe. Same fix.

[RonB]

I thought there was a fix for this...I don't remember the thread but it was in the last month or so. I guess the drivshafts are too short and some dealers have replaced them, some just reprogram the tranny to "hide" the problem, while others just turn up the sterio so the clunk is not heard.
I think there is a tsb on this.

Ron

[unaslob]

there is a fix for this.. there the problem is the slip yoke is too short.. the common sx of it is you get some hesitation, or slipping. there is a fix... it is a longer slip yoke...I thought they fixed it for the 2004

unaslob

Corsa Sport exhaust(offroad 'tip'), Gobi rack w/ lights & w/roof mounted tire w/ ladder, Warn Winch with rear power, Dual Wolo Airhorns w/ lanyard valve, Hadley Aircompressor 130PSI, 14" airtank, front and rear quick disconnects for air, Cobra 75 WX CB, Dual 4' Firestik fiberglass whips, front tinted windows, 7" Homer Simpson decal (teehee)!

[89vette]

The TSB about the driveshaft too short does not address a clunk if you read it. My dealer would not perform this TSB. There is another clunk that is heard when you stop the vehicle. This is not what I am complaining about. That noise is the tranny shifting into first. My dealer did reprogram the PCM to eliminate this problem. The clunk/thunk when I started moving is the slip yoke.

I could probably get my dealer to fix the problem but after two attempts I don't think it's worth the effort. My Hummer dealer is a GM Mega (biggest on East Coast) and their serivce department is like cattle hearding.

03 Sunset H2!
89 Vette
02 Escalade

[89vette]

I actually called my dealer and thanked them for their great service. They said thank you for your effort.

At any rate, I'm happy now. No klunks or rattles for that matter.

03 Sunset H2!
89 Vette
02 Escalade

[HUMMER SALESMAN]

I have noticed it after a off road session or track ride. A tech can remove the drive shaft and make some lube to the back. I just cycle it through 4 low, roll, then back, and it goes away. I was told there is compression at times on the back?

[89vette]

When you stop the truck the front dips and the back rises. This stretches the driveshaft and it moves out of the transfer case. When you accel the opposite happens and the slipyoke gets "stuck" on the output shaft of the T case. That is the thunk you hear. Sone grease will clear it up. For how long only time will tell.

03 Sunset H2!
89 Vette
02 Escalade