A buddy of mine came over to see me this evening with his 93 D250 Cummins Auto Club cab long box 205,000km(125,000miles). Said to me take my truck for a drive and tell me whats wrong. Jumped in, fired up, vibration started while backing out of my driveway! Not real bad, but definitely there. Into forward gear, and it would shake the fillings out of your teeth up to about 70kmh (45mph) then it all settles down. Frequency seems too high to be in wheels, tires, but I could be wrong (was one other time) ;D Driveline seems tight, no excessive play when shifting from R to D. Shut it off and let it coast and vibration was still there but not as pronounced. You can feel it in floorboards, steering wheel and seat. So I told him I would consult the DTR folks and see what they thought. So what do you think? Seized U-joint? Hanger bearing looked OK but ... Just checking. Thanks Rick. PS Don't know why he won't register here and post himself. Annoying part is he bought his truck because of how mine runs and doesn't break down. He's done diff, tranny. fuel pump, whl brngs etc. etc. in last two years. So far (knocking on wood) I haven't had to do a lot to mine.

 

I'd start with the u-joints, especially if you cut the engine in neutral and coasted but still have the vibe. The hanger bearing is a possibility too. The way I'd check that, since the vibe happens at low speed, is to rest the rear end on jack stands and put it in gear to watch the hanger bearing, at slow speeds.<br><br>Chris

 

Greatwhite, you have a u-joint that is dry and very tight more than likely. You'll find it when you pull the drive line, it'll be hard to move the u-joint if that's the problem.

 

Another U-joint problem that can cause vibration like that is a &quot;worn&quot; (for lack of a better term) yoke that doesn't hold the U-joint on center. Check for side-to-side play on both axes with no load on the driveshaft. There should be no discernable side-play. I had an old chevy that had that problem on the pumpkin end of the driveshaft. It would vibrate like hell from about 60 MPH up to 90, then was as smooth as silk.<br><br>Also, if you can feel vibration at low speeds, do like Stamey said, and check for a bent shaft and worn slipyoke.

 

Thanks for your help. Center joint seized, rear joint worn. All fixed up now. . He's off to Calgary to visit his new grandson this weekend. I keep telling him he's old ;D.