klunk on takeoff

[transgta]

My 01 supercrew when i take off i feel a little klunk but not hard or loud.It just seems like from the tranny back to rear end there must be some play in something. I did take driveshaft out and change u joint on front of driveshaft. After putting back in didnt seem to do it at first. Now its back sometimes when i hit brakes kinda hard at stop when i let off brake it does it to. Didnt know if i should change rear u joint cause these r not fun to change unless they r bad dont wanna do it for nothin. Gimme some advice THANKS DAVE

[transgta]

no one knows?

[bumthumb]

Check your universal joints for play.
Might also be excessive lash in the rear gears.
Good luck, bud!

[bumthumb]

Check your universal joints for play.
Might also be excessive lash in the rear gears.
Also try and coast down a hill, if you have a standard, clutch in and the out and give gas and see if clunk shows. sounds like universal.
Good luck, bud!

[cso18]

Do you have a two piece driveshaft? My old 70 F100 did the same thing. The problem was in the splines where the two shafts joined in the center. Over time, a small ridge developes in the splines causing them to bind. I heard GM had the same problems and sells a special lubricant for about $35. I found that Mercruiser U-joint & gimbal bearing grease works quite well, is much cheaper, and comes in sizes to fit most grease guns.

[transgta]

My driveshaft is one piece with a u joint on front and rear. Think ill try the rear u joint and hope thats it not gonna do it til sat so if anyone has anything else please type Thanks bumthumb and cso. for your reply

[cajunwolf]

Originally Posted by transgta

My 01 supercrew when i take off i feel a little klunk but not hard or loud.It just seems like from the tranny back to rear end there must be some play in something. I did take driveshaft out and change u joint on front of driveshaft. After putting back in didnt seem to do it at first. Now its back sometimes when i hit brakes kinda hard at stop when i let off brake it does it to. Didnt know if i should change rear u joint cause these r not fun to change unless they r bad dont wanna do it for nothin. Gimme some advice THANKS DAVE

i had the same problem on one of my truck and found out later it was the anti locking brakes engaging

[transgta]

cajunwolf how did u pinpoint it and what was the fix?

[Mrpiggy52]

What motor and trans is in the truck? You might check the tranny mount bolts. These stripped out of my 97 and had to redo them. Made that same kind of noise. You might also check on the exhaust manifold where it conects to the rest of the pipe.

Mrpiggy52