Coolant Reservoir

A coolant tank acts as a regulating component to the excess coolant that’s produced from the heat in your engine. As the warmth rises, coolant expands and overflows into the coolant reservoir and is then sucked back into the radiator as your car cools down after shut-off. Your vehicle relies on your coolant tank to readily accept the excess coolant with each cycle, and a crack or leak means constant replenishing and the possibility of overheating your engine. AutoZone is here to help you keep your cool with a selection of coolant tanks with trusted name brands to ensure lasting performance.

How To Find and Fix Coolant Leaks

Learn your way around the cooling system so you can spot and stop coolant leaks.

How to Check Your Coolant Level

Want to take a look at your car's coolant level? Learn how to check it and add coolant if needed.

Diagram showing the locations of major components in the engine cooling system

How the Cooling System Works and How to Maintain It

Your vehicle's cooling system keeps your engine from overheating by pushing coolant that is cooled in the radiator through passages on the engine block and head.

A woman tightening the lid on her vehicle's antifreeze reservoir.

What's Causing My Coolant Reservoir to Overflow?

Have you noticed an overflow coming from your coolant reservoir? This article highlights possibilities that could be causing your coolant to leave its closed system space.

Temperature gauge from dash instrument cluster

Common Cooling Problems

Maintaining a stable temperature is critical for your engine. Issues with cooling require quick repairs, but can usually be identified quickly or limited with preventative maintenance.