Driveline Shudder on 2500HD

BC2500HD · March 15, 2007

I have a 2003 GMC 2500HD with a 6.0L and 4spd auto. When the truck is cold there is a very noticable shudder from a stop. As the vehicle warms up it seems to get better, but is still there. About 8000 miles ago the dealer replaced the slip yoke and front u-joint, but I still have the same problem. Today the service manager of the dealer told me this in normal and that I'm just picky Is there anybody out there with the same problem? Is it the Posi, or maybe the the transmisson? Transfer Case?

BIGASSTRUCK · March 16, 2007

Have them turn the front rotors. When the rotors are slightly warped they are not flat. At slower speeds the vibration will be slower (slower rotation). As you drive faster, the vibration will have a higher frequency, as the rotors are spinning faster.

As they heat up they flatten out a little. That's why the problem goes away, but is still there a little bit even when they're hot.

As your brakes wear on, this problem will get worse and worse.

Ford (those other guys) had big problems with this exact thing in the late 90's & early 2000's. Many Ford truck owners complained of crappy front brakes (aren't all front brakes undersized?).

Our fleet had both Chev & Fords through 2002. The Fords all experienced this problem in a big way! We went through driveshafts, u-joints, balancing tires, front end alignments, ball joints, you name it. Until a young employee who's into off-road 4X4's suggested we look at the rotors.

And d**n if he wasn't right on the money...

Trouttrooper · March 16, 2007

What's your truck? EC, CC; SB, LB? There was some issues with driveline shudder on the longer wheelbases some years. Do a search and it should give you some ideas

Boomer73 · March 16, 2007

Where are you feeling the shudder?

I have a 2003 GMC 2500HD and am currently experiencing a lot of vibration/shudder at 62+ MPH. The transfer case shift handle just goes crazy. If I accelerate past 75mph and momentarily let up on the accelerator and then go right back on the accelerator its smooth as glass and quiet as can be until the speed come back down to 65ish. Then its like someone is going at the transfer case with a jackhammer again. The dealer has no clue what the problem is. He too checked the yoke an u-joints and said everything looks fine. His answer, "Well its going to have to get a lot worse before we can do anything about it and/or we can replace random parts if you like."

BC2500HD · March 17, 2007

Have them turn the front rotors. When the rotors are slightly warped they are not flat. At slower speeds the vibration will be slower (slower rotation). As you drive faster, the vibration will have a higher frequency, as the rotors are spinning faster.

As they heat up they flatten out a little. That's why the problem goes away, but is still there a little bit even when they're hot.

As your brakes wear on, this problem will get worse and worse.

Ford (those other guys) had big problems with this exact thing in the late 90's & early 2000's. Many Ford truck owners complained of crappy front brakes (aren't all front brakes undersized?).

Our fleet had both Chev & Fords through 2002. The Fords all experienced this problem in a big way! We went through driveshafts, u-joints, balancing tires, front end alignments, ball joints, you name it. Until a young employee who's into off-road 4X4's suggested we look at the rotors.

And d**n if he wasn't right on the money...

The problem I am having is from a dead stop, just as I accelerate, then goes away. It feel like maybe the "Gov-Loc"(posi) is sticking or something? Or maybe from the pinion angle changing on acceleration? I am going to do a 4 wheel brake job soon, so I'll see if this maybe the problem. Thanks

BC2500HD · March 17, 2007

What's your truck? EC, CC; SB, LB? There was some issues with driveline shudder on the longer wheelbases some years. Do a search and it should give you some ideas

My truck is a EC/LB with the huge aluminum drive shaft. Which I believe is the one piece unit. Do you have any suggestions on where to find more info? Thanks

perform95 · March 17, 2007

The problem I am having is from a dead stop, just as I accelerate, then goes away. It feel like maybe the "Gov-Loc"(posi) is sticking or something? Or maybe from the pinion angle changing on acceleration? I am going to do a 4 wheel brake job soon, so I'll see if this maybe the problem. Thanks

is it in the the engine cold and you touch the gas it kinda jerks ..... my 06 2500hdCC does it ..

BC2500HD · March 17, 2007

Where are you feeling the shudder?

I have a 2003 GMC 2500HD and am currently experiencing a lot of vibration/shudder at 62+ MPH. The transfer case shift handle just goes crazy. If I accelerate past 75mph and momentarily let up on the accelerator and then go right back on the accelerator its smooth as glass and quiet as can be until the speed come back down to 65ish. Then its like someone is going at the transfer case with a jackhammer again. The dealer has no clue what the problem is. He too checked the yoke an u-joints and said everything looks fine. His answer, "Well its going to have to get a lot worse before we can do anything about it and/or we can replace random parts if you like."

The problem I am having is only from a dead stop, not on the highway. I did have the truck into the dealer for the same problem about 1 year ago. I believe there is a TSB(technical service bulletin) for the slip yoke going into the transfer case. They replaced it, under warranty, with a high nickel content yoke. (More durable I guess?) They also replaced the U-joint at the front of the driveshaft. In doing this repair they didn't install the u-joint properly and i also got a bad vibration at around 65mph, but went away if you slowed down a couple mph. They put a new u-joint in and the high speed vibe went away.

Ch2500HD · March 17, 2007

I'm not sure if we have the same problem or not but it sounds similiar and maybe it will help you. I have an '03 2500HD EC/SB w/ 6.0 motor. My truck developed a tendency to jerk/shudder from a stop; however, mine did it when it had been running a while. I took it to the dealer several times. They checked: wheels, rotors, alignment, update the shift points in my trans computer, i didn't need the slip yoke or u-joint. This still did not fix my problem. I started researching this site and found that it could be the fluid in my axle. So I had the dealership do a complete fluid change my next time in: oil, transfer case, transmission, and differential. That was about 9 mths and over 8,000 miles and I have experienced the problem again. So in short, have the dealer check your differential fluid and make sure you have the correct additive in there for the G80.

Ch2500HD · March 17, 2007

I'm sorry that should have said, I have NOT experienced the shudder again

BC2500HD · March 17, 2007

I'm not sure if we have the same problem or not but it sounds similiar and maybe it will help you. I have an '03 2500HD EC/SB w/ 6.0 motor. My truck developed a tendency to jerk/shudder from a stop; however, mine did it when it had been running a while. I took it to the dealer several times. They checked: wheels, rotors, alignment, update the shift points in my trans computer, i didn't need the slip yoke or u-joint. This still did not fix my problem. I started researching this site and found that it could be the fluid in my axle. So I had the dealership do a complete fluid change my next time in: oil, transfer case, transmission, and differential. That was about 9 mths and over 8,000 miles and I have experienced the problem again. So in short, have the dealer check your differential fluid and make sure you have the correct additive in there for the G80.

What is the G80? Is that the differential model? I did read on another post that, maybe the clutches in the Posi were sticking or "hanging up". In my case it seems to get better as the vehicle warms up. So maybe the fluids in the truck have warmed up, or the viscocity has changed? Thanks for the info.

Boomer73 · March 17, 2007

Maybe you have a torque converter going bad? After you get going and the shudder goes away, have you noticed a change in firmness of the transmission shifts at all?

BC2500HD · March 18, 2007

Maybe you have a torque converter going bad? After you get going and the shudder goes away, have you noticed a change in firmness of the transmission shifts at all?

I haven't noticed any difference in the shift firmness, but I'll keep an eye on it to see. Thank you

desrtrat · March 19, 2007

Where are you feeling the shudder?

I have a 2003 GMC 2500HD and am currently experiencing a lot of vibration/shudder at 62+ MPH. The transfer case shift handle just goes crazy. If I accelerate past 75mph and momentarily let up on the accelerator and then go right back on the accelerator its smooth as glass and quiet as can be until the speed come back down to 65ish. Then its like someone is going at the transfer case with a jackhammer again. The dealer has no clue what the problem is. He too checked the yoke an u-joints and said everything looks fine. His answer, "Well its going to have to get a lot worse before we can do anything about it and/or we can replace random parts if you like."

try rotating your tires. if you still get a lot of vibration try rotating your drives shaft 180* undo the ujoints at the diffs and turn them180*. MAKE SURE that your e brake is set and put it in neutral engin off of course and see if that helps. it just sounds like a balance issue... my .02

good luck

wht2500hd... · March 19, 2007

mark the shaft before you remove it; this sounds like excessive drive line angle if you are carrying plenty of weight at the rear of the bed. when you nail it the differential rotates and temporarily changes the angle. when cold idle rpm is higher.