The Diesel version of Mobil 1 that you're thinking about is Delvac 1. Hard to find and expensive, at about $22-$25 per gallon. My E300 has happily run about 50,000 miles on Amsoil Heavy Duty Marine and Diesel engine oil (15W-40). You can get it delivered to your door from http://www.lubespecialist.com for about $16 per gallon.

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Rick Miley
2014 Tesla Model S
2018 Tesla Model 3
2017 Nissan LEAF
Former MB: 99 E300, 86 190E 2.3, 87 300E, 80 240D, 82 204D Euro
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