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Is Synthetic Oil Bad for Diesel Engines?
I own a 2007 Ford 6.0 liter diesel F250, and was told at the dealership that Mobil 1 would void my warranty. Also, people I talk to swear that synthetic oil is bad for diesel engines. Why is this statement being made? I swear by Mobil 1 and won't use anything but.
-- Pete Soderling, Pueblo West, CO
We have an outstanding Mobil 1 diesel oil for diesel engines and it is called Mobil 1 Turbo Diesel Truck. Since this product is a 5W-40 engine oil it would be perfect for your vehicle especially since it can get pretty cold in Pueblo West in the winter and pretty hot in the summers. The 5W-40 viscosity will protect on both ends of the temperature spectrum. The product was recently reformulated and upgraded to API CJ-4, and it continues to meet older categories such as API CI-4, CH-4, etc. With the exception of Mobil 1 Turbo Diesel Truck, you should not use other Mobil 1 products in your diesel engine.