Damoc55amg

Hey guys hope this is in the right place new to this forum!
so this one for the brains trust of these Mercedes platforms
problem I am having is a strange thumping noise (similar to a tow bar Tung loose ect) coming from the rear end of my c55 but only after driving up a large mountain range with load on the car it’s a very pronounced noise as if something is loose and only does it until I guess it cools down again for maybe 5 minutes ? The. It goes back to dead silent maybe the odd knock here nor there
Weird I know
car has had replaced the lower outer rose joints in the hub new rear shocks and springs (Bilstein coilovers)
everything else seems to be okay? Thinking internals of one of the mufflers coming loose and under the added heat after a long haul knocking ? Not sure has anyone else come across this sort of thing on any w203 platforms

Stephen04E55

get it on a lift and check everything from sway bar attachments, strut bolts, toe arms, control arms wheel bearings, etc. Give everything a good look-see and press on the wheels, shake components to see if anything has noticeable play. Use a little flashlight and look closely at the condition of the rubber bushings in the innards of the arms. Check tightness of all components just to be sure. Check the driveshaft and condition of the bolts attaching to the rear.

Damoc55amg

Have done all of the above did find today one of the exhaust hanger mounts is mounted incorrectly (not sure when in the last 20 years I would have been touched) but it has been banging on the muffler hanger quite a lot moved that and tried it seems to be solved! But I’ll give it a week or 2