Not sure if this belongs here, but I am not sure what the problem is so I have to start somewhere. This has happened twice in as many weeks. I will come to a complete stop, and when I take off, I feel and hear a loud clunk, like if I had something in the box and it rolled back and hit the tailgate (but there is nothing in the box). Anyone have any ideas? Everything seems normal after with no unusual noises or anything except the clunk when I start out.

Anyone? No one has any ideas? I find that hard to believe...

I'll get an occasional bump like someone tapped into me,no clunk although.

I would try greasing the driveshaft spline,that is why I get it.

really?? was is that ? mine does it to I thought it was my brakes hanging up or something like that. cool i will give it a try. thanks

Just gets sticky dry I guess , you'll feel the bump when the suspension recoils. Mine will do it stopping and starting off.

Since I lasted greased it many moons ago it stopped,I since changed U-joints and didn't grease the spline and it's back.

I don't get a clunk although like the thread starter so I dunno if he has pinion slop,low on rear differential fluid or what.

I get a clunk as soon as I take my foot off the brake after almost any kind of stop. My mech. says it is normal for these trucks.



I know, it sounds like a generic answer, but I trust him and he knows these trucks. He works on them at the dealership.

This has always been a common problem on GM trucks since 99'. WOW I thought they had fixed it but I guess not. There was actually a TSB out on my 99' on replacing the rear slip yoke with a different one that was Nickel Plated. The Factory one would stick and when you stop your rear end compress and the yoke would stick and when you let off brake to take off the yoke pops back out and thats the clunk you feel. Do what the aboe said, take off your driveshift and grease the inner yoke and slide her back in and you will not feel it anymore.

Rear diff is good, I changed the fluid this summer. Sound is kinda hard to describe, but it sounds like what is being described above. I will try the grease. Thanks.

thats why I love these threads they help us out in a pinch

I had the same problem. I needed to change out my U joints, so when I did that, I also, pulled the driveshaft out and lubed it. No more clunck, squeak or anything. Good as new!! Also, new U joints have zerk fittings. Hope they will last a little longer. Got 75,000 on factory ones.

yeah i would check the u joints then grease the splines on the shaft

Is your truck positive- limited slip traction? I also had a clunk one time. Had very heavy gooseneck load. Started from stop and made a right turn at the light. Very loud clunk and could also feel it. I wondered if I broke something in truck or trailer. Couldn't find anything, wondered if my posi traction had kicked out since was I was making a turn.

I believe it does. I was kinda wondering about that myself. It only occassionally does it, but everything else seems fine. I guess I will not worry about it unless it gets worse, or when the warranty is close to up, I will have it checked.