The trouble with making assumptions about the care and use/treatment of any used trans. is just that - a guess. Forensically speaking, when you open 'em up, all is clear - except how the car was driven.

I can make a case for the fact that some trans.' are destined to fail long before the 100K mark. The reason(s) why are unclear though. One would have to believe that either the trans. was faulty, it's associated system(s) failed, or, the hard use given those trans.

I can make a case that in service time and miles, changing the fluid/filter(s) was unnecessary, to a fine working trans.

Knock on wood, none of our (6) (most bought new) MB AT trans. have failed in up to nearly 500K miles of use on one. With well over 1 Mil miles collectively - no fails.

Have had super good luck with American-branded cars' AT trans. too - with the exception of a GM /FAIL @ 60K miles.

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'06 E320 CDI
'17 Corvette Stingray Vert