2019 Honda Odyssey Coolant Capacity & Type

The 2019 Honda Odyssey holds approximately 10.8 quarts (10.2 liters) of coolant in its total cooling system, though a standard drain and refill requires about 7.6 quarts (7.2 liters). As an ASE-certified master technician, I can tell you that maintaining the cooling system on this fifth-generation Odyssey is vital for the longevity of its 3.5-liter V6 engine, especially when you're hauling a full load of passengers or towing.

Quick answer

• Total cooling system capacity: 10.8 quarts (10.2 L) for a dry fill/overhaul; ~7.6 quarts (7.2 L) for a typical drain and refill.
• OEM coolant spec: Honda Long Life Antifreeze/Coolant Type 2 (Blue). This is a Phosphated Organic Acid Technology (P-OAT) formula that is completely free of silicates and borates.
• Mix ratio: 50/50 pre-mix. Honda Type 2 comes pre-diluted from the factory. Do not add water, as this will throw off the boiling/freezing point and anti-corrosion protection.

Capacity by engine option

For the 2019 model year, Honda simplified things by offering only one engine option across all trim levels (LX, EX, EX-L, Touring, and Elite).

Note: Capacities include the engine block, radiator, heater cores (front and rear), and reservoir tank. Always buy at least two gallons for a standard drain and fill.

Flush interval

Honda relies on its Maintenance Minder system to alert you when it's time for a coolant flush. When sub-code "5" appears on the dash, it is time to replace the engine coolant.

• Normal duty (Factory fill): The original factory coolant is designed to last up to 10 years or 100,000–120,000 miles.
• Severe duty & subsequent flushes: After the initial factory fill is replaced, the fresh coolant should be flushed every 5 years or 50,000 miles. If you frequently tow, idle for long periods in heavy traffic, or drive in extreme climates, stick to the 5-year/50,000-mile interval.

How to refill & bleed

Because the 2019 Odyssey is a minivan equipped with dual climate control (front and rear heater cores), bleeding the system of air requires a little extra attention.

1. Prep and Drain: With the engine cold, remove the radiator cap. Open the plastic petcock at the bottom of the radiator to drain the old coolant. Close the petcock securely once drained.
2. Setup the Funnel: Attach a spill-free coolant funnel tightly to the radiator filler neck. This elevates the fill point above the highest part of the cooling system, helping force air bubbles out.
3. Fill the System: Slowly pour Honda Type 2 50/50 coolant into the funnel until the radiator is full. Top off the plastic overflow reservoir to the MAX line.
4. Run the Engine: Start the engine. Turn both the front and rear heaters to their highest temperature settings with the blower fans on low. This opens the valves to both heater cores.
5. Bleed the Air: Let the vehicle idle until it reaches normal operating temperature (you will know it is there when the radiator cooling fans cycle on at least twice). Watch the funnel—you will see air bubbles burping out. Keep the funnel topped up so it doesn't suck air back in.
6. Final Check: Once the bubbles stop, turn off the engine. Remove the funnel, install the radiator cap, and double-check the reservoir level after the engine has cooled down completely.

Common cooling system issues

The 2019 Honda Odyssey is generally very reliable, but there are a few cooling system quirks to watch for as the mileage creeps up:

• Water Pump Replacement: The 3.5L V6 uses a timing belt that must be replaced around the 100,000-mile mark. It is industry standard (and highly recommended) to replace the water pump at the same time, as it is driven by the timing belt.
• Wrong Coolant Usage: Using a universal green IAT (Inorganic Acid Technology) coolant instead of the blue P-OAT Honda Type 2 can rapidly degrade the water pump seals and lead to silicate dropout, which clogs the rear heater core lines.
• Radiator Tank Seepage: As the vehicle ages and undergoes thousands of heat cycles, the plastic end tanks on the factory radiator can develop hairline stress cracks, leading to slow coolant weeping and eventual overheating.

If you aren't comfortable tackling a coolant flush or need a timing belt and water pump service, leave it to the professionals. Find a trusted shop on Repairius.