the flanges have the sunken bosses for the protusions.

The offset type disc is to cushion the "downshift" as you slow down with the old fully hydraulic automatics - the later electronic ones use the same solid disc front and back as the transmission itself is very well behaved and the "receiving generation" of these cars dont complain much on the downshift nudges.

MB went a step ahead to even remove those nudges with those offset type discs.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)