I have a 2000 2dr 4wd 4-ltr with 115k miles standard trans. Under slow acceleration I get a deep heavy vibration sound and feel. When parked the front drive shaft can be easily rotated back and forth about a half inch or so, the rear drive shaft is solid. Could the front drive shaft movement be the problem?

Sounds like your u-joint is goin!

whip front drive shaft off, go for a drive, if vibration gone well that would be it....

good luck

The U joints are tight. Back to the rotational play of the front drive shaft. Do others have this play, could it be the cause of the deep vibration sound and feel? Thanks for thinking about it.

If the vibration is more related to engine RPM than road speed you might consider the trany mount.

Does sound like a U-joint though. You did jack it up?