I really dont know how to explain it but here goes. When I pull up to a stop sighn, usually with a complete stop, my truck almost feels like the chasis shifts a little forward. Then when I press on the gas to go it shifts back a little; however, it is intermitent. Any ideas? It is a 2001 2 wheel Drive 52,000 miles, ext. cab, long bed.

Take the drive shaft out and dab your finger into a tub of grease and rub vigorously in the splines of the drive shaft where it goes into the transmission and reinstall it, you got the ol yoke stickin thing going I bet, when I purchased my truck that is EXACTLY what it felt like. Takes all of 20 minutes to fix, and doesn't cost anything, except a finger dab of grease...........

yup, that solved mine. Be generous with the grease though, and make sure it is quality. Some is better then none, but may help the problem to stay gone longer.

If you have a two-piece drive shaft, it's not the piece that goes into the trans, it's the slip yoke in the middle of the two shafts that's the problem. Don't see it as much on those, but it does happen. Some of these have a zerk (grease) fitting on 'em, but I don't recall what years.

Thanks guys for the info ... I'm having the same issue on my 02 crew cab. I only feel it when I'm empty ... goes away with weight on the hitch.

I'll grease it up this weekend

Thanks,
Kevin

Awesome Thank you very much I will try that this weekened.

That is interesting, that it goes away with weight on the hitch. I wonder if pushing the suspension down either at stopping or letting off the brake makes the driveshaft give. If it is greased you don't feel it. If it is a little dry if it starts to tug, then lets go? Any thoughts?

I still feel mine do it when I am towin my fifth wheel.

Any change at all? The first time I did mine it was a little better, I took apart again and added more grease. Then it was resolved.

Pulled it apart today, and like you said there was not even one drop of greese on the splines. It was as dry as could be. Going to drive it to work tommorow and will let you know.
Thanks

That solved my problem.

Great! Interesting that this seems to be a GM issue. I never hear of Fords or Dodges having this issue..... Course, I try not to hang with those kinds anyway!!):h

Sounds just like what is happening to my wife's Cherokee. Will lube the splines and see.

Andy

Let us know.

If it is greased you don't feel it. If it is a little dry if it starts to tug, then lets go? Any thoughts?

This is exactly what's happening. It's called a"stick/slip" condition. When you stop or take off, the rear suspension moves up or down a bit and the shaft has to be able to slide in or out of the tranny to make up for the change in length. The splines on the yoke momentarily stick then with additional pressure, they slip, but it happens suddenly, causing the clunk you hear.

In fact, this is the exact same problem as the intermediate shaft steering clunk. It has splines just like the driveshaft yoke. Over bumps, the body and the frame move a bit in relation to each other. The I-shaft has to be able to change length to accomodate this movement. The splines between the I-shaft and the lower shaft momentarily bind, then suddenly release, giving you that clunk feel in the wheel.

Makes sense, thanks.

could it be 20gals of diesel sloshing around?

This is exactly what's happening. It's called a"stick/slip" condition. When you stop or take off, the rear suspension moves up or down a bit and the shaft has to be able to slide in or out of the tranny to make up for the change in length. The splines on the yoke momentarily stick then with additional pressure, they slip, but it happens suddenly, causing the clunk you hear.

In fact, this is the exact same problem as the intermediate shaft steering clunk. It has splines just like the driveshaft yoke. Over bumps, the body and the frame move a bit in relation to each other. The I-shaft has to be able to change length to accomodate this movement. The splines between the I-shaft and the lower shaft momentarily bind, then suddenly release, giving you that clunk feel in the wheel.


This would be the same for 4x4's I would assume? When the driveshaft is disconnected from the rear diff, does it just pull right out of the slip yoke? Thanks.

Mine is 4x4, and yes, once you unbolt ujoint at rear end (remember to mark lines on the ujoint to rear end yolk so it goes back exactly as it came off) it slides out from tranny. I had to get a short pry bar and pry slightly against the rearend yoke to get it to move towards front of the truck first, holding my knees up against it so it wouldn't hit the floor. Then it pulled right out. Use lots of quality grease. I had to do mine twice as didn't put enough in the first time.

Thanks for the info, did it last night in 30 minutes, it's a beautiful thing and works great. Appreciate it. :thankyou2