Engine Oil

Engine Oil Selection

1. Engine Oil Quality

Use Only Oils conforming to API Service CI-4. A sulfated ash limit is specified for lubrication oil used in Cummins engines. Oils with a high ash content may produce deposits on valves that can progress to guttering and valve burning. A maximum sulfated ash content of 1.85 mass % is recommended for all oil used in the engine

2. Engine Oil Viscosity (SAE Grade)

Above 0°F (-18°C) 15W-40

Above -20°F (-29°C) 5W-40 Synthetic

The proper SAE viscosity of engine oil for the expected ambient temperature range should be selected.

NOTE: The same oil change interval is to be followed for synthetic oil as for petroleum based oil. Also, synthetic oil must meet the same performance specifications as petroleum oil.