Vibration under acceleration
Just trying to figure out why my truck vibrates while acceleration, it never did this before and has done it for a couple months now, so we havnt been using it.
It vibrates at any speed while under acceleration, once u let off the accelerater it stops vibrating. you can somewhat cruise and it wont vibrate too bad but once u try to accelerate more it starts vibrating immediatly.
There is also a noticable humming noise in the drivetrain, only under accleration also, once u let off the gas, it stops.
When in park the driveshaft seems to have an easily moveable 1/4'' of play. but the U-joints dont seem to be loose, seems to be moving the whole part that comes out of the transmission? when you go from drive to reverse, or reverse to drive it makes a pretty loud clunk.
Also i pulled on the rear wheeles pretty hard in and out to see if there was any play which there didnt seem to be any.
any ideas of what all this could be?
figured id give as much info as possible, thanks guys.