2001 LB7, lifted 6" 36" Swampers, front end makes thumping noise when slowing going over speed bumps or pot holes...will make the same noises when turning off road...I RARELY if ever took this truck off road...it's never been abused...I replaced the intermediate steering shaft because I've read on a lot of threads that has been a problem with all 99-06 models...noise is still there....replaced the ball joints last year...noise never went away...sway bar end links are good...thinking its the CV axles...I got under the truck this morning and checked for loose parts...and the CV axles were the only parts with play in them...my duramax has 180,000 on her and the CV's have never been replaced...any ideas?

 

I have the same problem in my 04 its stock. I had the front end checked out and replaced the hub and right tie rod. Nobody seems to know what it is let me know if you find something out!
It happens when turning left or right and going over bumps and its been going on for a while now

 

is it more of a clank, clunk, pop or thump?

try putting washers on the front crossmember bolts both sides.

 

I had the same problem.

If your on the brakes does it go away?

Check brake calipers for too much movement with the wheels off, grab the caliper where it slides back and forward, and see how much play that has...mine would rattle like a bitch over bumps sounding like the front end was falling out, put 2 new front calipers and it was like new.

Another sound I had was a banging on ever wheel rotation, bad wheel bearings, one side bad did them both. Usually most thing like that you do in pairs.

If ones bad the other ain't far behind it

 

There are a bunch of different components it could be... Tie rods, ball joints, idler arm, pitman arm, wheel bearings. Gotta check them all

 

Well, I've replaced the Wheel Bearings/Hubs, Ball Joints, Tie Rods, CV Axles, and checked the Pitman Arm and Idler arm...I guess I'm going to try the washer trick...hopefully it'll do the trick. 199,000 out of all of those other parts ain't too bad if you ask me.

 

200k is amazing!