You are right that the pink color of ATF fades pretty quickly to brown and resembles motor oil. Place drop of your motor oil and a drop of your trans fluid on a piece of paper towel and spray it with an alkaline all purpose cleaner like Fantastik. The ATF will bleed pink.

Your W210 has a built in diagnostic system to monitor your oil and remind you of when to change it. It's called FSS and is covered in the OM. To take advantage of the extended service cycle you need to use a polyester fleece filter (Mann 718/5x) and a MB approved synthetic oil (MB 229.3 or 229.5) such as Mobil 1 Syn 0W-40 European Car Formula as mentioned above.

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Good luck.






1998 E320 Wagon