Yesterday my truck started to jump once each time
i stopped at a light or stop sign. Today it seems to be fine. I just wanted to know if anyone else has had this happen and what might have caused this. Thanks

If you had the tow/haul button pressed while you were coming to a stop that was probably it downshifting into first gear and "clunking". I dont typically use the tow/haul setting while while coming to a stop while emtpy/no trailer as this is what happens...

Try it with and without button pressed, you'll see. Especially if you come to a quick stop.

Mike

sticky slip yoke?

i know that it wasn't in tow mode. That was the first thing i checked.
Thanks for your replies.

does it have a rough idle my truck has a surge at idle that i cant figure out how to get rid of.

When I first got my ATS back in November, the valve body was faulty and would shift from 2nd down to 1st stoped at a light and would jarr the truck forward. They said it was a sticking valve. That and a few other issues with the valve body. Installed a new body (warranty) and perfect since then.

I think I got the same problem with mine. It just started doing the jarr forward in the last few weeks. Truck now has 66500 km's.

Remove drive shaft and lube the yoke splines.

It won't cost you nothing, except for a dab of grease, and about 30 minutes of time.

It fixed mine everytime, every 25-40,000 miles or so.....

If the yoke splines need greasing, does that mean the splines are possbily getting worn out? I took it to the dealer last week to get there opinion on it and it turns out I had an leaf insulator missing on the one side, put a new one in there but still getting the jarring feeling.
The other day I turned into a parking lot and as I hit the accelerator, it seems like the trans. slipped, so I backed off the throttle and everything seemed fine afterwards. Then yesterday on the way home same thing after turning onto another street and then hit the accelerator, it did it again but this time the engine light came on. I checked the code with my Predator and got P0500, Vehicle speed sensor malfunction. Dropped in at the dealer tonight and he put his Tech II on it and it actually threw a P0500 and 2 P0700 codes and the 1st P0700 code was generated the 1st time it happened but the Predator didn't show that code? Dealer metioned they can't look at it until next wednesday as they're booked solid. The advisor at the dealer cleared the codes so hopefully the trans. shifts better, etc. but on the way home, another P0700 (TCM - Trans. Control Module). Just wonderfull, a long weekend for us here and I can't even hit the accelerator without it going into safe mode and then I half to shut it down so it resets and then it's ok to go but you got to be easy on the throttle. This really sucks! Still got the drivetrain "clunk" and now trans. issues.

No they are not worn, mine has 176000 miles, and I lube them and they are fine.

Yes the isulator will give sone feeling, but the spline lube will fix you right up.

OK, thanks "Tolliwacker". I'll grease up the splines tonight or this weekend.

Do you think this clunk/spline is what might has caused the TCM (P0700) & Speed (P0500) Sensor code malfunctions?

It should not cause any codes, just the jolt at the stop and go....

Well, I didn't get around to greasing the splines. Kid got invited to play in a hockey tournament, 6 games and there goes the weekend.
By the way, will any fluid leak out of the T-case when I pull the driveshaft out? Should I elevate the rear of the truck before pulling out the ds?

Torque converter would be my guess.....

If level no leak, but you might have another problem, but the splines lube won't cost you anything......Then go from there.

Well, finally got around to greasing the splines and the clunk is gone. Sure was easy to do. Thanks everyone. This site is great. You can always find someone to help.

Ron