My '88 300E's transmission is slipping on upshifts between 2nd and 3rd and 3rd and 4th. Once it catches, it gives quite a jolt. The fluid and filter where replaced 50,000 miles ago (car has 211,000). Could the necessity of a fluid and filter change be causing this?

I also have an opportunity to purchase a rebuilt transmission for about $1500. It has 8,000 miles on it since a rebuild by Peter Schmidt. Anybody have info on Peter Schmidt, I'm told he's a well know MB transmission specialist.

If I need a new transmission, which makes more sense, the above described transmission, or having a reputable shop do it locally? (I'm guessing dollarwise it may come out the same)

Thanks in advance!!

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http://www.belmontgroup.com/images/300Ewcolor.jpg

'88 300E 265K
'91 300TE 155K