About 8 quarts (7.6 liters) of engine oil, with the filter, using Dexos1 Gen 2 0W-20.
The 2021 GMC Sierra 5.3 L V8 uses a standard oil capacity and viscosity specification published by General Motors for normal operation. This article explains the exact quantity, the recommended oil type, and practical maintenance guidance to help owners perform a proper oil change and keep the engine running smoothly.
Oil capacity and specifications
The following specifications apply to the 2021 Sierra equipped with the 5.3 L EcoTec3 V8. They reflect GM’s official guidance for typical service intervals and are intended to help owners plan their maintenance.
- Oil capacity (with filter): 8 quarts (7.6 liters).
- Recommended oil type: Dexos1 Gen 2, viscosity 0W-20.
- Notes: The capacity includes the new oil filter; always verify the level with the dipstick after a change and top up as needed.
Bottom line: plan for about 8 quarts of oil and use the Dexos1 Gen 2 0W-20 specification when performing an oil and filter change.
Maintenance and service reminders
Beyond the capacity, understanding the maintenance approach helps ensure reliable operation. GM vehicles in this class use a sophisticated Oil Life Monitoring System that estimates when an oil change is due based on driving conditions and usage.
- Oil change interval: Typically around 7,500 miles (12,000 kilometers) under normal driving, but the Oil Life Monitor will trigger service when needed. Severe service (extreme temperatures, heavy loads, frequent short trips) may shorten this interval.
- Checking oil level: After the engine has cooled, check the dipstick to confirm the level sits between the Min and Max marks. Add oil gradually if needed and recheck.
- Filter and fill practices: Use a GM-approved oil filter and ensure the engine is properly lubricated by following the full fill to the recommended level before running the engine.
Always consult the owner’s manual or the vehicle’s Oil Life Monitor for your exact interval, as regional recommendations and driving conditions can affect maintenance timing.
Summary
For the 2021 Sierra with a 5.3 L V8, the engine oil capacity is 8 quarts (7.6 liters) with the filter, and the recommended oil is Dexos1 Gen 2 0W-20. Use the vehicle’s Oil Life Monitoring System to determine the precise change interval and verify the oil level with the dipstick after refilling. When in doubt, refer to the owner’s manual for your specific configuration and driving conditions.