this is my 03 yukon xl I'm referring to.

After new shocks and new boxed lower control arms (from Spohn -same part # as Impala SS) w/ all kinds of greasable fittings -I wasn't able to stop the squeaking.

I've finally narrowed it down to the drive shaft into the rear-end. I've noticed that everytime the torque changes the pinion angle, I get the squeak. It happens when on the gas and the rear-end squats. It happens when braking hard and the rear-end settles. It happens when you are on the gas and going over speed bumps, but does not squeak if you just roll over speed bumps.

I'm at a loss. Any ideas?

 

sounds like you are having drive shaft clunk. take the drive shaft out and install some special lube in the end of the yoke

 

Thanks. I'll look into that. It does sound like a metallic squeak. I wonder where I can find the lube? I've got some synthetic lubes I might try.

 

Standard moly-based lube is what is reccomended by GM, the actual fix is a brass-plated yoke that the dealer can install...this issue has been creeping up in these trucks since '99 so it's nothing new

 

Thanks! I was waiting on that phrase "brass plated" because I'd heard of some fix before but couldn't remember.

 

Well...after a year and a small amount of cash out the window...I took you guy's advise and pulled the shaft, lubed the yoke, re-installed and all is well! All fixed...done!
Thanks

 

just like folks said, the squawking sound is working itself back. I used the moly-based lube and it worked great for a while.

The squawking and the clunk combined are more than I can stand. I'm taking it to the dealership tomorrow.

 

TAKE A SMALL RUBBER BOUNCY BALL, CUT IT IN HALF, SLIDE IT IN THE YOLK. THEN LUBE THE SPLINES AGAIN... i WORK AT A DEALER AND WE HAVE DONE THIS SEVERAL TIMES!!!!

 

awesome idea...it's at the dealer today to get checked out. I'll use that if I have to. Thanks!