My 300SD failed suddenly, it had 281k and one day I drove to the lake, parked, went to reverse from my parking spot and it lurched then had a whooshing noise, things went downhill from there...forward gears still worked, but reverse was very weak. Ended up finding pieces of the reverse band/clutch in the pan once I swapped it out for a good used one. (which has been installed for 42k+ with no issues)

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-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)