2024 GMC Sierra 1500 Coolant Capacity, Type & Service Guide

The 2024 GMC Sierra 1500 holds between 11.6 and 14.0 quarts (11.0 to 13.2 liters) of coolant, depending on the engine option equipped. As an ASE-certified master technician, I regularly service the cooling systems on these modern GM trucks, and using the exact fluid specifications and bleeding procedures is critical to keeping these sophisticated engines running at optimal temperatures.

Quick Answer

• Total Cooling System Capacity: 11.6 to 14.0 quarts (11.0 to 13.2 liters), varying by engine size.
• OEM Coolant Spec: DEX-COOL® (Orange), OAT (Organic Acid Technology), GM Specification GMW3420.
• Mix Ratio: 50/50 mixture of DEX-COOL concentrate and clean, drinkable water (preferably distilled or deionized), or a 50/50 pre-mixed solution.

Capacity by Engine Option

The 2024 GMC Sierra 1500 is offered with four distinct powertrains. Because of differences in block sizes, radiator dimensions, and auxiliary coolers, the total cooling system capacity varies. Here is a breakdown by engine:

Note: Capacities are approximate and represent a completely dry system. A standard drain and fill will typically require slightly less coolant.

Flush Interval

GM's DEX-COOL is a long-life OAT coolant, but it still requires regular replacement to prevent corrosion and maintain its heat-transfer capabilities.

• Normal Duty: Replace the coolant every 150,000 miles or 5 years, whichever comes first.
• Severe Duty: If you frequently tow heavy loads, idle extensively, or drive in extreme heat or dusty environments, it is recommended to inspect the coolant regularly and consider flushing the system closer to the 100,000-mile or 4-year mark to ensure maximum engine protection.

How to Refill & Bleed

Modern GM trucks, particularly those with the 3.0L Duramax and the V8 options, have complex cooling routes with multiple high points that can easily trap air. A vacuum-fill tool is highly recommended.

1. Preparation: Ensure the engine is completely cold. Locate the surge tank (coolant reservoir).
2. Vacuum Fill (Recommended): Attach a pneumatic vacuum coolant filler (like an Airlift tool) to the surge tank. Draw a vacuum on the system to collapse the hoses slightly and verify there are no leaks. Open the valve to let atmospheric pressure push the pre-mixed DEX-COOL into the system, completely eliminating air pockets.
3. Manual Bleed (Alternative): If you don't have a vacuum filler, slowly pour 50/50 DEX-COOL into the surge tank until it reaches the cold fill line.
4. Run the Engine: Leave the surge tank cap off. Start the engine and turn the cabin heater to its highest temperature and lowest fan setting.
5. Warm Up: Let the engine idle until the thermostat opens (the upper radiator hose will become hot). You will likely see the coolant level drop as trapped air escapes.
6. Top Off: Carefully add coolant to the surge tank to maintain the level at the cold fill line. Install the cap tightly. Test drive the vehicle and recheck the level after the engine has fully cooled down.

Common Cooling System Issues

While the 2024 GMC Sierra 1500 is a relatively new model, it shares architecture and engine families with the previous few model years. Based on those, technicians keep an eye out for:

• Water Pump Weepage: The V8 engines (5.3L and 6.2L) occasionally develop slow weepage from the water pump gasket or weep hole over time.
• Radiator End Tank Leaks: The plastic end tanks crimped onto the aluminum radiator core can separate or crack after years of thermal cycling.
• Thermostat Failures: Electronic and traditional thermostats can stick open, triggering a check engine light for the engine running too cool.
• Diesel Complexity: The 3.0L Duramax has specialized cooling valves and a complex thermal management system that requires precise bleeding; air pockets here can cause localized overheating that might not immediately register on the dash gauge.

If you suspect a leak or need a professional coolant flush, don't leave it to chance. Find a trusted shop on Repairius.