there have been similar shifts in preferred engine oil viscosity grades. An example is the transition in heavy duty diesel engine oils in the 1980s from monograde viscosity SAE 30 and SAE 40 to ...

Lastly, 6.7 Power Strokes frequently burning B20 biodiesel fuel require either Motorcraft SAE 5W-40 full synthetic diesel motor oil or SAE 15W-40 Super Duty diesel motor oil. More than just ...

Additives in the oil were used to neutralize that acid ... engines have trended significantly away from the popular diesel SAE 15W-40 and 10W-30 viscosity grades. Newer automotive gasoline ...

Should heavy-duty motor oil be recommended, it's likely because your vehicle's engine is diesel-powered ... duty oils like Valvoline All Terrain SAE 15W-40 are intended to provide a considerably ...