2019 Ram 2500 Coolant Capacity & Type

The 2019 Ram 2500 has a total cooling system capacity of up to 28.8 quarts (27.2 liters) for the 6.7L Cummins diesel engine or 16.5 quarts (15.6 liters) for the 6.4L Hemi V8 gas engine.

Quick Answer

• Total Capacity (6.4L HEMI V8): 16.5 quarts / 15.6 liters
• Total Capacity (6.7L Cummins Turbo Diesel): 28.8 quarts / 27.2 liters
• OEM Coolant Specification: Mopar Antifreeze/Coolant 10 Year/150,000 Mile Formula OAT (Organic Additive Technology)
• OEM Part Number & Color: Mopar MS-12106, Purple
• Mix Ratio: 50/50 distilled water to antifreeze concentrate, or use a pre-mixed 50/50 solution.

Capacity by Engine Option

The required coolant capacity for your 2019 Ram 2500 depends entirely on the engine installed. The significantly larger and harder-working Cummins diesel requires a much more robust cooling system with a higher capacity.

Flush Interval

Following the recommended service interval is critical for protecting the aluminum and iron components in your engine from corrosion. The Mopar OAT coolant is a long-life formula, but still requires periodic replacement.

• Normal Service: Replace coolant every 10 years or 150,000 miles, whichever comes first.
• Severe Duty Service: Ram considers vehicles that frequently tow heavy loads, operate in extreme hot or cold climates, or spend a lot of time idling (like commercial work trucks) to be under "severe duty." Under these conditions, it is recommended to shorten the interval to every 5 years or 100,000 miles to ensure maximum cooling system protection.

How to Refill & Bleed

Refilling and bleeding the cooling system on a 2019 Ram 2500 is crucial to avoid air pockets, which can cause overheating. While a DIY job is possible, these modern trucks benefit greatly from a professional vacuum-fill procedure to ensure no air is trapped in the system.

1. Mix Coolant: If using concentrate, mix it 50/50 with distilled water in a clean bucket. Do not use tap water, as its mineral content can cause scaling and corrosion inside the radiator and engine.
2. Slowly Refill: With the engine completely cool, slowly pour the 50/50 mix into the coolant reservoir (de-gas bottle) until it reaches the MAX fill line.
3. Bleed the System (6.4L HEMI): The 6.4L engine is generally self-bleeding. After the initial fill, start the engine with the heater on high and the reservoir cap loose (but still in place). Let the engine run for 15-20 minutes, or until the thermostat opens. You will see the coolant level drop as air is purged. Top off the reservoir as needed.
4. Bleed the System (6.7L Cummins): While it can also self-bleed, the Cummins engine's complex cooling circuit (including the EGR cooler) is notoriously difficult to bleed completely without special tools. A vacuum-fill tool is highly recommended. This tool pulls the entire system into a deep vacuum, removing all air before coolant is drawn in to fill the void. This is the most effective method to prevent stubborn air pockets and potential overheating issues.
5. Check and Re-Check: After the initial run cycle and cool down, re-check the coolant level in the reservoir and top off as necessary. Check it again after a few drive cycles.

Common Cooling System Issues

The 2019 Ram 2500 is part of the fourth-generation platform and has a generally reliable cooling system. However, some issues are known to occur, particularly on the hard-working Cummins models:

• Water Pump Failure: The water pump is a wear-and-tear item. Symptoms of failure include a coolant leak from the front-center of the engine, a whining or grinding noise, or engine overheating.
• Radiator Leaks: Plastic end-tanks crimped onto the aluminum radiator core can develop leaks over time due to constant heat cycles and pressure. Look for drips or the smell of sweet coolant after parking.
• EGR Cooler Issues (6.7L Cummins): The Exhaust Gas Recirculation (EGR) cooler uses engine coolant to cool down exhaust gases. These coolers can fail internally, leading to coolant consumption with no external leaks, white smoke from the exhaust, and potential engine damage if left unchecked.
• Thermostat Failure: A thermostat stuck closed will cause rapid overheating. A thermostat stuck open will cause the engine to warm up very slowly and may trigger a check engine light.

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