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nykx
May 5th, 2004, 08:29 AM
hey gang... i was driving to werk the other day, about 35 mph - and all of a sudden, there was a violent vibration accompanied by a teribbly loud rumble. i stepped on the clutch and it went away. i step off the clutch and there it is again. i slowed to 10-15 mph and drove the half mile to werk. i but it up on blocks and began tinkering. i thought maybe one of the wheel bearings went but after chking they all seem fine. from under the truck, i rotate the front drive shaft - moves fine, smooth. but when i try to rotate rear drive shaft, it seems to rotate half a rotation smoothly but to make a complete rotation takes great effort, there seems to b considerable resistence. also, when rotating the rear drive shaft only the right wheel turns... is this normal? or is it of sign of sinister things? any help would b greatly appreciated!! BTW its a '95 d-90, with 95k miles.

thx - nick:confused
Mike Hippert
May 5th, 2004, 09:03 AM
When you rotate the rear driveshaft both tires should turn, try pulling the axle out of the side that does not turn. You could also remove the fill plug on the diff and stick your finger in to check for metal on the oil.
nykx
May 5th, 2004, 10:09 AM
i pulled the axle out of that end and it looks fine. the spline is nice and clean.
Mike Hippert
May 5th, 2004, 10:21 AM
So with it off the ground and the T-case in neutral you can spin the rear driveshaft, and 1 tire spins. If you spin that tire does the other tire spin?
nykx
May 5th, 2004, 11:42 AM
that is correct. when i spin that wheel, the other wheel spins in the oppisite direction... WTF?
Mike Hippert
May 5th, 2004, 11:51 AM
Wait a second, ( brain kicking in) if it is hard to rotate the driveshaft every 1/2 turn that would mean that it's something with the driveshaft, the drum brake or Pinion gear, as anything in the diff after the pinion would have a problem when you rotate the DS every 3.54 times( the gear reduction of the R$P). So take a good look at the U Joints on the rear DS, if they look OK then pull the DS off, I have had UJs look ok and then I pulled the DS and they would not move. If thats not it, try spinning the rear diff and Drum brake.

Sorry for the brain not kicking in sooner.