I'm sure the single cam sixes will run fine on mid-grade, but for the 104 twin cam six, I'd stick with premuim. I run Sunoco Ultra 94 in my 300E and in return I get excellent fuel economy and smooth running. You definitely can't run anything lower than premium in a V8, and from what I was told when I worked at the dealer, Mercedes recommends premuim to keep the cats and everything clean and in top condition. I tried running mid-grade in my DeLorean but found it to run horrible. It seems to like Sunoco 94 like the rest. Just my $0.02.


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Rgds,
Aaron Greenberg
MB technician
Precision Motorcars, Cincinnati, Ohio
'67 250SE Cabriolet
'77 450SL
'80 300SD
'85 380SE
'89 420SEL
'93 300E 2.8
'74 Jensen Interceptor Mk.III
'81 DeLorean DMC12
'85 BMW 745i Turbo