one factor, with that mileage, you are near the end or beyond the typical expected life of a BMW auto trans (which would cost about as much to replace with a reman as you will pay for the car). That is one thing I've heard that MB has the advantage on BMW. Obviously, how the cars were drive, maintained, luck, etc. play a role in how long the trans in any car will last.

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2005 Mercedes C230k sport sedan, 6 speed
1987 Porsche 924S - 968-engined track car