Originally Posted by
BossGMC
If your hearing a clunk in the rear that sounds like the leaf springs are popping or the brake shoes are sticking, I recommend you remove your driveshaft and grease the inside splines if the input yolk, what happens is that the yolk no longer slips in and out of the trans output shaft, and when you brake the rear of the truck comes up extending out the shaft, then when the weight comes down the shaft travels back in and binds making the popping sound like a clunk, that's what I have ran across many time at the dealership I work at, wont hurt to look at that possibility, let me know what you find out...