The 2018 GMC Sierra with the 5.3 L EcoTec3 V8 holds 8 quarts (about 7.6 liters) of engine oil when you perform an oil change with a new filter. This is the standard capacity listed by GM for the 5.3 L V8 in that model year.
Official capacity and its meaning
Oil capacity refers to the total amount of oil the engine sump can hold when completely filled. For the 5.3 L EcoTec3 V8 in the 2018 Sierra, GM’s spec lists 8 quarts (7.6 liters) with the filter installed. This value guides how much oil you should add after draining the old oil during a full oil-and-filter change.
Practical notes for maintenance
When changing the oil, use the recommended Dexos1 Gen 2 oil and a compatible filter. After installing the new filter, add oil until the dipstick shows the full mark on level ground. While 8 quarts is the standard figure, always confirm the exact specification for your vehicle using the owner’s manual or a GM-certified technician, as regional variations or VIN-specific guidance may apply.
Oil grade considerations
Most regions for the 2018 Sierra's 5.3 L engine call for Dexos1 Gen 2 oil, typically in the 0W-20 or 5W-30 viscosity range depending on local climate and emission requirements. Always verify the recommended viscosity in your manual, and ensure the oil meets GM’s Dexos1 Gen 2 standard. The capacity remains 8 quarts with filter, regardless of the exact viscosity chosen.
Summary
For the 2018 GMC Sierra's 5.3 L V8, the engine oil capacity is 8 quarts (7.6 liters) with the filter installed. Verify the exact specifications for your vehicle in the owner's manual or with a GM-certified technician, and follow proper oil-change procedures to reach the correct fill level.