Rearend clunk-pinion moves up and down?!

[fordmanSLO]

Hey everybody, got something I just can't figure out. From a stop to takeoff, I get a big clunk from the rearend. Happens when I come to a complete stop too. I look under while the lady drives, and I see the rearend pivot and the pinion will shift up and down.

When I first got my lift done, superlift 5.5, I had a problem like this but much worse, and the shop guys said I needed shims. They pretty much fixed it, but I still get a clunk, if the ujoints are freshly greased, it isnt as bad, but I don't like the idea of the rearend moving like that.

Any ideas? Thanks

 

[88vert]

whne you did your u-joints did you grease the slip-yoke on the driveshaft?

 

[fordmanSLO]

yep, and it helps a little, but what I'm really worried about is the movement of the rear axle, because as far as I know, that should not be happening

 

[RiverRat]

The pinion shouldn't move "up and down" Someone might not have preloaded the bearing incorrectly or the bearings are shot. Either way, It would be a good idea to get that fixed.

 

[RFR2212]

Um, driveshaft U-Joints... If ya did a SOA lift in the rear, are your spring perches welded fully?

them are my iders

 

[GaSouthern1]

Yea, tighten the crap out of your U-Bolts, that is probably your problem. Your perches may even be bent and in that case you would need some new ones but that is doubtful.

 

[Byrd91]

Yeah sounds like spring perches to me. If you have the Superlift SOA kit in the rear you need to rig something up so that it cannot pivot. The u-bolts alone will not hold it. A good, cheap, reversable method would be to weld some flat bar from the old perches to the new. A shop could do it in 10 minutes.

 

[Hokie]

mine clunks on brakeing... alas i'm too lazy to grease my slip yoke on the drive shaft right now