Why dose the 8.1 litter ask for 5W30 shouldn't it need a higer viscosity
Hello, Oil type depends on many factors, such as the mileage on your vehicle, climate, and type of driving you do. I would recommend visiting a site such as http://www.valvoline.com and seeing what they recommend for your specific needs. You can plug in your car and information and check out their results. Best of luck! CarGrrl
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