Answer: Use 5W-30 engine oil that meets GM’s Dexos1 Gen 1 specification (preferred). If Dexos1 isn’t available, a GM-approved 5W-30 oil that meets API standards is acceptable. The engine holds roughly 6 quarts of oil with a filter.
In more detail, the 2008 GMC Sierra 1500 with the 5.3-liter V8 relies on modern engine oils to protect its timing and longevity across varied driving conditions. While the exact specification can vary by market or vehicle history, the guiding rule is to pick a 5W-30 oil that meets Dexos1 Gen 1 or GM-approved API specifications, and to follow the factory capacity and maintenance intervals listed in the owner’s manual. Always verify the exact requirements for your specific truck with the manual or a dealer if you’re unsure.
Recommended oil type and specifications
The following options cover the key aspects you should consider when selecting oil for the 5.3L V8 in a 2008 Sierra 1500.
- Viscosity: 5W-30 is standard for most climates and usage patterns
- Specification: Dexos1 Gen 1 (preferred) or GM-approved API-rated oil
- Oil type: Synthetic blend or full synthetic is acceptable and may offer better protection
- Capacity: Approximately 6 quarts (5.7 liters) of oil with a new filter
Concluding: Following these specifications helps protect the 5.3L V8 and supports reliable starts, fuel efficiency, and engine longevity. If in doubt, reference the owner’s manual or consult a GM-certified technician for your exact vehicle build.
Oil capacity and change intervals
These figures help you plan maintenance and avoid under- or over-filling the sump.
- Oil capacity: About 6 quarts (5.7 liters) with a filter
- Change interval: Typically 3,000–5,000 miles for conventional oil; 5,000–7,500 miles or more for synthetic oil, depending on driving conditions
Concluding: Regular oil changes using the correct oil grade and capacity are essential for engine longevity, especially in trucks that see varied use like towing or frequent city driving.
Practical steps for an oil change
Below is a concise guide to performing a routine oil change on a 2008 Sierra 1500 with a 5.3L V8, whether at home or at a shop.
- Warm the engine, gather oil, a new filter, a drain pan, and tools
- Drain old oil by removing the drain plug and collecting the used oil
- Remove the old oil filter and install a new one with a light coat of fresh oil on the gasket
- Refill with the recommended 5W-30 oil (about 6 quarts, depending on your exact engine)
- Check for leaks, run the engine briefly, then recheck the oil level with the dipstick
Concluding: A careful, tool-equipped approach ensures a clean change, proper oil level, and lasting engine protection.
Why the right oil matters
Using the correct viscosity and specification helps protect timing components, reduce wear, and maintain performance in the 5.3L V8 across extreme temperatures and loads. Dexos1 Gen 1 certification is GM’s preferred specification, ensuring compatibility with engine seals and the oiling system.
Summary
The 2008 GMC Sierra 1500 with the 5.3L V8 should use 5W-30 oil that meets Dexos1 Gen 1 (preferred) or a GM-approved API-rated 5W-30 oil, with an oil capacity of roughly 6 quarts including the filter. Adhere to the maintenance schedule in the owner’s manual and consult a GM-certified technician if you’re uncertain about Dexos1 eligibility or climate-specific recommendations. Regular, properly specified oil changes support engine longevity and performance for this popular pickup.