On a 722.6 you should only ever put MB fluid and a MB filter in their. Do not put anything else in their.

Besides the dealer charges just under $200 for a fluid change, just have them do it. They have the special tool that will measure the fluid temp so they can get the level right. Some things are just not worth doing yourself, what are you saving $100 by doing it yourself? To risk a $3k trans?

My friend had his done for the first time at 152k and it shifted a bit better. I would just change the fluid.

Also I am not 100% but I am pretty sure the original color of this fluid is not red, I think it may be a clean motor oil color. But I am not 100% sure.

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2009 C300 4matic
1969 280SE
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