I've been trying to figure out why my truck jerks and clunks on takeoff, while shifting gears, and when getting on and off the gas. It's quite annoying and makes it a total bitch to drive, especially trying to drive slow, like in a parking lot at the store. I've done some poking around and have figured out that it's excessive lash (or play) in my rear diff. It's not axle wrap, the rear leafs are fine. With the truck parked and the tranny in neutral, you can rotate the drive shaft about a 1/4 turn. The clunk and jerk is the gearing moving through the slop and then all of the sudden it finally all makes contact and gets the wheels turning. Of course when you let off the gas everything gets rotated by force of the wheels, instead of from the drive shaft, thus taking up the play in the opposite direction, and setting up for another clunk and jerk when I hit the gas again.
From when I have read, there is a way to adjust the amount of play in the gearing, I'm just not sure what all is involved, other than taking apart the axle and removing the 3rd member. This is also assuming that my gears aren't trashed. Anybody have any suggestions or info on adjusting a rear end?