96_12V

Okay I'm listing this in drivetrain section as it must be related to the output shaft from the transmission, or the rear end, or something else...? But I'll suspect those two areas to start as they just saw some service.

What I'm noticing is a vibration you feel in the middle of your back while steady-state driving with the truck at around 35 - 45 mph in fouth and sometimes fifth gear. I noticed it this weekend and it seems to be more prevelant when everything's warmed up. In fourth gear it'll about make your teeth chatter. Above this speed, and below it, in any gear it's normal, no problem.

I mentioned the service I just had done. The local Dodge dealer changed the rear differential fluid, changed the output shaft seal from the transmission (beginning to leak) and also the front cover seal and front main seal on the engine. It really does not seem to be coming from the engine.

I plan to take the truck back to them with this, but am wondering ahead of that time if anyone may have insight into what could be going on. Thanks for any input!

Crimedog

I would suspect the driveshaft *may* be out of balance. It is possible that when they removed it to do the seal they didn't mark the spots and put it back in the same place, or it could have dropped a balance weight when it was on the ground. If you look at the driveshaft at the rear axle there should be some sort of mark so they could line it all back up again, if there isn't they probably didn't get it back in the same spot. That's what I'd put my bet on.

96_12V

Great suggestion, Crimedog - I'll have them check it out.

But I think I may have found part of the problem - and boy was it ever weird! Backing out of my space at work this afternoon, I ran over something hard. Looking down, I notice a large piece of metal about 3" round and rust all around it. I get out and see it's an ISOMOUNT. I set it in my bed and look at the cab - can't see anything obvious missing, but I DO feel it. There's a slight rocking motion now to the cab. First thing at 7:00 tomorrow it's at the dealer beign checked out.

Perhaps I should put on a sticker more accoustumed to old British cars:

The parts falling off this truck are of the finest American quality!