Out of curiosity, what causes a B2 piston to break? I spoke to a inde Mercedes Repair shop, and they say:

"Oh...Theres something wrong with the transmission because the B2 piston is seriously damaged blah blah blah $2,100 to rebuild trans or blah blah blah Something is broken in the trans blah blah"

Before the B2 failed my trans is shifting fine, it downs shifts and up shifts smoothly, and engages every gear properly. So back to the question, What causes a B2 piston to break?

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Current Garage
2008 Mercedes GL320 CDI 188k mi Repair/Work in progress
1994 S350 160k mi Garage Queen & prepping for repairs
2005 E320 CDI 203k mi Healthy & Daily Driver
1994 S350 357k mi Retried as parts car
1984 300TD 214k mi Blown OM617 Poss OM603 Swap??

Sold
1987 300SDL 200K+
1994 S320 181K mi
2008 E320 Bluetec 127k mi
1999 S420 130K mi
1980 240D 360k mi
15+ Others that has come, stay and gone

GONE, BUT NOT FORGOTTEN
1995 E320 SE 220k mi
1984 300SD 350k mi