Mercedes does offer rebuilt transmissions, they will take your unit and replace it with a rebuilt unit.

First, before you jump to the worst case scenario,

These transmissions are heavily integrated with electronics and computers, so having a dealership pull diagnostic codes may be the first thing to do.

Second when the car is up on the lift a quick look for any loose connections, leaks or even collapsed engine mounts or broken transmission mount plus broken flex disc.

Also a fluid and filter change done to see if it cures anything, is an idea.

Could even be a slight chance of MAF sensor n the air-intake causing the problem.

Good like with other replys and use the SEARCH