MikeThomas

Arggggg, Ive got this vibration in my truck from 55 to about 73mph... crusing speed of course. Ive had the tires balanced twice...two replaced for being out of round under warrantee. So I called the driveshaft guys to set up a time to balance my d-shaft, but, they said before I bring it it to drop the shaft and run it up to speed to see if there is still a vibration. I do that before work and I find that there is a small vibration at those speeds....its not as bad, though I assume it because its not under load. Is there something in the T-Case or Tranny that could be the source of my vibrations? Its a scarry thought to me, but Im fed up with the vibrations.

flashgordon

If the only question of the tranny or t-case is vibration.....start with the drive shaft.

Before I put my Gear Vendor Overdrive unit in my truck i had a smiler vibration.
The drive shaft had to be shorted and they just started with a fresh on.....
Vibration gone..............

Check to make sure the yoke it tight to the t-case,......if you can move it up and down.........this could also be your vibration!

Flash

jdwest

My truck is doing the same darn thing, just between 58-68 mph. So far I've replaced u-joints twice and had the driveshaft balanced. I've also had it alligned and just put new tires on it. It helped a little. It used to vibrate badly at light load/constant speed before the balance. Now it does it only slightly. If under load though, it still shakes like a wet dog between 58-68. The splines on the rear driveshaft slipjoint are a little worn. I'm beginning to think it would be in my best interest to have the driveshaft rebuilt and go from there. As far as I can tell tranny and xfer-case is tight. Could a worn/broken clutch possibly cause the vibe? Any other thoughts?

cootz

Mike I'm assuming you've replaced all your rear U-joints? I had the same symptoms and it was the center U-joint near the carrier bearing that was the culprit. Fixed the vibration, drives like new.

Also, make sure there is no wear at the yokes, they may need replacing. If all that checks out, the carrier bearing may be at fault.

I was doing some browsing last weekend at the recall list and came upon this one that seemed interesting. Perhaps this is what your problem is.

http://dodgeram.info/tsb/1993/03-02-93.htm

MikeThomas

cootz, excellent link. I have the one piece shaft so Im going to have to check my pinion angle because when I lay on the fun pedal she vibrates bad, but I have always thought it was torque/cummins thing.

Fred Swanson

Mike, I have another shaft you can try, from the donor truck.

MikeThomas

Sweet, do you think its the same length auto vs manual?

brainfade

I've been chasing a bad vibration for a while now, adjusted the pinion angle, new U-joints, balanced driveshaft, new output bearing in the 205, nothing helped. Finally broke down and rebuilt the transfer case - new input and rear output shafts, new bearings everywhere. Spent about $800.00 plus my labor. That took care of the really bad one, but I've still got a rumble between 50 and 55 mph. Still scratching my head on that, but at least I can drive the truck.

On mine, the thing that lead me to the transfercase was that I could push up and down on the driveshaft at the case end, and the output shaft would move in such a way that it looked like it was pivoting about where the output bearing rides. Took it apart and nothing really looked bad, but there was a couple thousands wear on all the bearing races. Guess that was enough to cause the vibration.

BTW - A driveline vibration will have a lot higher frequency than an out of balance wheel.

Fred Swanson

Mike, good point, the auto will be shorter. The one I have is 55 3/8 from center to center.