WHY is the only transmission that works with a 1978-80 300SD a 722.120? If I used a 722.3xx transmission, it won't work? It's the same OM617 engine as the rest of them. You would think all of the transmissions would be interchangeable like the engines are. FRUSTRATING!!!

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Current fleet-
1993 Mercedes 300SD
2004 Chevy Avalanche 4x4
2009 BMW 535i xDrive
1995 Saturn SL2
1993 Mercedes 300SE (parts car)

Previous Benz's-
2001 Mercedes SL500
1983 Mercedes 300SD
1980 Mercedes 300TD
1996 Mercedes E300D
1999 E300DT
1984 300TD-T
1988 Mercedes 560SEL (parts car)
1979 300SD
2003 E500
2004 S430 4Matic
2001 E55
2003 E430