My 300E has 200k miles, and shifts as-new with Red Line Syn ATF (which has been in there since the car had 68k miles, and had 2 dino fluid changes in its prior history). My 500E has over 100k on it (with well over 50 track days) and still shifts very well (but I'll admit that under part throttle, the 2-3 shift slips a bit when it's cold). I've heard great things about SWEPCO, though, so on your advice Neil I think I'll try it next time. Do they have a fully syn product?

One of my good friends runs a trans rebuild shop, and recommends synthetic to anyone who will listen. But regardless, he says frequent changes can do nothing but help (I do my 300TE at 30k mile intervals, the 500E is more like every 15k).

FWIW.

__________________
"If God had meant for us to walk, why did he give us feet that fit car pedals?" Sir Sterling Moss

Michael
2014 E63S Estate
2006 SLK55
1995 E500
1986 Porsche 944 turbo