clunk clank clunk!!!!!!Please Help

[dieselman]

Another new mercedes-300TD. I have a little problem. On acceleration the trans seems to jerk into gear. I also noticed a noise if I pumped the pedal while sitting in the car from the rear end. Sort of a clanking noise. I had someone pump the pedal while I looked at the rear with a flash light. It is at the end of the drive shaft. It seems to be twisting a little while pumping the pedal and clanks. Basically it looks loose or like it is moving when it should not while in park. What does this mean?

Thanks,
Dieselman