Here is my dilemma

This is the best way I can describe it.
When driving at some speed, while in C mode and the car goes to up shift and I slow down (break) at the same time I get a thud/thumb sound in the rear (or at least that’s where I feel it is)

Now car is fine, its just I am not sure why I get this effect every now and then.
Some have said to change the transmetion mounting on the car.

Now my question is this, if these are changed (engine & transmition mountings) are they any effects? Bad at all?

Just a little over worried that I am fixing something that doesn’t need fixing and could cause other problems to arise :-/

Your opinions would be greatly appreciated

 

I had this very occasionally when the G/Box would engage harshly on a delayed upshift into trailing throttle... and clunk. Not a pleasant sound as I doubt the box would sustain allot of these.... Has not happened again for a very long time...

I would do a tranny ECU reset.... see here for method, should help, if not take it to dealer.

https://mbworld.org/forums/showthrea...ight=reset+ecu