Hi All,

Have a weird vibration issue and looking to see if anyone can help.

Background: Truck is a 1996 2500 4x4 and I have already replaced the following as they have needed it: Rear driveshaft ujoints, front control arms, shocks and coil springs, all bushings, hubs.

Last winter started to have a clicking noise when in 4 wheel drive as well as a vibration at highway speeds. Pulled the front driveshaft and it needs replacing as the slip joint has lateral play and makes noise when you push on it sideways.

Ran the truck w/o the front shaft and a lot of the noise etc was gone but still have a vibration that only occurs when under load. Coasting the vibration is gone.

Rotated tires made no difference. I checked the rear ujoints and they are still good. I did notice that the transmission mount has some separation of the rubber to metal base as well as a squeak when you try and pry up on the transmission.

Could this cause this weird vibration?

Going to be ordering a new driveshaft and will order a new mount as well if it will help.

Thanks for any assistance!

 

Don't think it's a driveshaft issue..... it's still spinning whether under load or not.

Not a miss is it???

 

Replace the trans mount and see what happens. Under load it may be moving to far out of alignment.

 

Under load the driveshaft will exhibit rotational torque and if the slip joint is sloppy is will flex. Mine flexs and makes noise when I test it on the bench so I cannot imagine how badly it does this when under load from the v8

 

Mount was replaced today but not able to test it until I get a new ditributor in it.

I did notice drivers side motor mount has a lot of play and squeaks to that will be replaced as well.