bad vibration
 

hey guys I'll probably go the the GTG once I figure out a bad vibration. its a 97 F250LD 5.4L. When I'm on the gas from a stop it will vibrate real bad and once I get off of the gas I can still feel it but not as bad. Its driving me nuts. Also when I turn a corner I hear a click in the rear end, and it acts like it the tires are fighting each other when I take a 90* corner. Any help would be appriciated.

sounds like the ring and pinion are getting chewed up. i had this happen in my truck.

I put the rear up on jacks and started it up, then put it in gear. I can watch the driveshaft wobble back and forth..it almost looks out of round. what would cause this

try replacing the u joints. they are probably worn. with the truck on the ground, is there any excess play in the drive shaft if you try to turn it by hand with no load on it? it may help to also get the driveshaft rebalanced

Does your drive shaft have a lot of play in it when you try to turn it by hand? Are your universals all good and lubed? It could be just bad universals causing your problems. Is there lube leaking out of either your transfer case or rear pinion? I would check your diff fluid to see if there is metal shavings in it.

Report back as to what you find. Your truck is a 4x4 right?

ya the truck is 4x4.. I found the culprit. bad rear u-joint.. but I noticed something else.. when the truck is up on the jacks and its in park I can rotate the tires pretty far until it stops. I can do this in both directions. could it be the clutch packs going???

Check your rear diff fluid and see if there is metal in there. If so, it is possible.