took the front section of the rear driveshaft out at work cuz they have way more tools. front u joint was seized. wouldnt move left of right. even hitting it with a hammer wouldnt free it up so obviously i replaced it. that took care of all vibrations up to 40 mph. so i fixed half the problem. now all u joints are replaced in the rear shaft. only thing i did not replace was the carrier bearing but it had no slop or play what so ever. any ideas as to where to go from here?

 

Make sure that all the ujoints in the shaft are operating in the same plane. If the slip joint in the middle of the shaft is off by even one spline, you will get a vibration.

 

they all are. this is very agrivating that i can not figure this out. i refuse to take it to a shop and have it fixed

 

Famous last words.

 

Did you mean hanger or steady bearing? I would change it out, if it makes no diff then keep it as a spare.

Edit; Dually Dana 70-80 rear, have you jacked up the back of the truck and checked for slop in the rear wheel bearings/hubs, e brake dragging?

 

no play in wheels. and the e brake cable broke from the previous owner and is tied up

 

+1.... We used to solve a lot of probs at my old mans parts store/machine shop back in the day when hanger bearings were more common.

 

i mean the carrier bearing in the middle of the drive shaft not the pinion or carrier bearing inside the diff

 

Yea, that's the hanger bearing. Old school talk anyway.

 

well is it worth replacing if there is no slop in it?