I use Mobil 1 in my 91 300E. After over 150K it is still going strong with nice controlled shifts. I am due for another fluid change in the next couple of months and will be going with Mobil 1 again. I don't think the brand or type of fluid is as important as the frequency of service. Change the fluid and filter every 25K to 30K and you should be good to go.

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08 W251 R350
97 W210 E320
91 W124 300E
86 W126 560SEL
85 W126 380SE Silver
85 W126 380SE Cranberry
79 W123 250
78 W123 280E
75 W114 280