Factory coolant change intervals: two examples

Two 2026 maintenance schedules show how intervals are written. Your vehicle may differ:

From the 2026 Toyota Corolla Warranty and Maintenance Guide and the 2026 Ram 1500 Owner's Manual (publication 104308_26_DT, edition E2), read November 4, 2026. Ram says its OAT coolant can be used up to 10 years or 150,000 miles before replacement (page 323).

When to change coolant sooner

Mileage is not the only trigger. The 2026 Ram 1500 Owner's Manual says to check the engine coolant (antifreeze) protection every 12 months, before the onset of freezing weather where that applies, and that if the coolant is dirty or rusty in appearance, the system should be drained, flushed and refilled with fresh coolant. It also says that if the coolant is dirty or contains visible sediment, an authorized dealer should clean and flush the system.

Mixing coolant types can cut the change interval short. Ram says that if a non-OAT coolant is added in an emergency, the cooling system will need to be drained, flushed and refilled with fresh OAT coolant as soon as possible, and that mixing HOAT and OAT coolant is not recommended. If your engine has been running hot, read why a car overheats before you add anything.

From the 2026 Ram 1500 Owner's Manual (Engine Coolant Checks and Adding Coolant, page 323), read November 4, 2026.

Use the coolant your manual specifies

Coolants are not all the same. The 2026 Toyota Corolla Owner's Manual says to use only Toyota Super Long Life Coolant or a similar high-quality ethylene glycol based non-silicate, non-amine, non-nitrite and non-borate coolant with long-life hybrid organic acid technology. For the U.S., it says Toyota Super Long Life Coolant is a mixture of 50% coolant and 50% deionized water. It also warns that coolant is neither plain water nor straight antifreeze.

Ram calls for Mopar Antifreeze/Coolant 10 Year/150,000 Mile Formula OAT meeting material standard MS.90032 in the 2026 Ram 1500, and says not to use water alone or alcohol-based coolant products. Check your own owner's manual for the exact specification.

From the 2026 Toyota Corolla Owner's Manual (Coolant selection, page 303) and the 2026 Ram 1500 Owner's Manual (page 323), read November 4, 2026.

Checks between changes

Look at the coolant reservoir with the engine cold. The 2026 Toyota Corolla Owner's Manual says the coolant level is satisfactory if it is between the MAX and MIN lines on the reservoir when the engine is cold, and to add coolant up to the MAX line if the level is on or below MIN. If the level drops within a short time of replenishing, it says to visually check the radiator, hoses, reservoir caps, drain cock and water pump, and if you cannot find a leak, to have the cap and cooling system tested. Never remove the reservoir cap when the engine is hot.

Step by step: how to check coolant. For other fluids and filters, see our car maintenance schedule basics.

From the 2026 Toyota Corolla Owner's Manual (Engine coolant, page 303), read November 4, 2026.

Coolant flush at Elgin Auto Sales & Service Center

Our service department works on all makes and models, and Coolant Flush is one of the service types on our online service request form. Bring your maintenance guide or tell us the mileage, and we can check whether a coolant change is due.

Our service department at 1200 E. Chicago St. in Elgin is open Monday to Friday 8 a.m. to 5 p.m. and Saturday 8 a.m. to 4 p.m., and is closed Sunday. Schedule service, see our service specials or get directions.