Engine Oil

for 2021 Chevrolet Silverado 2500HD 6.6L V8 Duramax L5P · 4WD

Fluid Type

15W-40 CK-4 or 5W-40 full synthetic CK-4

Spec: API CK-4 or CJ-4

Capacity

10qt

9.46 L

Drain & Refill

10 qt

9.46 L

Change Interval

5,000 mi

8,045 km

Notes

Duramax L5P diesel. Capacity with filter. GM recommends dexos2 5W-30 full synthetic or 15W-40 for heavy-duty use. Oil change interval depends on oil life monitor.

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Other fluid systems on this vehicle

Automatic Transmission

17.4 qt

Washer Fluid

1.3 qt

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🔧 Database maintained under the daily editorial review of Chris Hackleman · Master Technician · 20+ years and Jeff Moore · Master Mechanic · 20+ years. Spot an error? Use the Help link above — a human reads every report.

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