Coolant Expansion Tanks for WRX, BMW, Miata & Mustang

What Expansion Tanks Cover

Coolant Reserve and Recovery

An expansion tank provides space for coolant volume changes as the engine heats and cools. The current collection includes direct-fit coolant expansion tanks, universal tanks and selected supercharger coolant tanks for specified performance vehicles.

Coolant Expansion Tanks

Engine Cooling System

A coolant expansion tank must match the hose connections, cap arrangement, mounting points and system design of the vehicle. Do not substitute a tank based only on appearance because cooling-system routing and pressure requirements vary.

Supercharger Coolant Tanks

Separate Cooling Circuits

Some supercharged vehicles use a separate intercooler coolant circuit with its own tank. Confirm whether a listing supports the engine coolant system or the supercharger circuit because they have different plumbing and service requirements.

Direct-Fit Applications

Match the Exact Vehicle

Current listings cover selected WRX STI, BMW M3, Miata, Mustang, Camaro, Corvette, Charger and Challenger applications. Confirm year, trim, engine and cooling circuit in the product listing before ordering.

Cooling System Service

Pressure and Leak Checks

Replace a cracked or leaking tank with the correct application-specific part, then inspect hoses, caps, clamps and coolant condition. Fill and bleed the system using the vehicle procedure and check for leaks once the engine reaches operating temperature.

What We Stock

• Moroso. Direct-fit and universal coolant expansion tanks plus supercharger coolant tanks.
• Koyo. All-aluminum reservoir expansion tank applications for selected Mazda Miata models.
• Granatelli. Heat exchanger tank applications for selected Corvette Z06 models.
• Subaru WRX STI. Coolant and intercooler tank applications for selected model years.
• BMW M3. Coolant expansion tank applications for selected E30, E46 and E90 generation cars.
• Mazda Miata. Coolant expansion tank applications across selected NA, NB and NC generations.
• Ford Mustang. Coolant expansion tank applications for selected S650 models.
• Chevrolet Camaro. Supercharger coolant tank applications for selected ZL1 models.
• Dodge Charger and Challenger. Coolant and supercharger tank applications for selected performance models.
• Lotus Elise and Exige. Direct-fit coolant expansion tank applications for selected model years.

How to Choose the Correct Expansion Tank

• Confirm whether the tank is for engine coolant or the supercharger circuit
• Match year, make, model, trim and engine exactly
• Verify all hose ports, cap location and mounting points
• Check whether a cap, sensor or hardware is included
• Inspect hoses and clamps when replacing a leaking tank
• Use coolant approved for the vehicle and climate
• Follow the correct fill and air-bleed procedure
• Confirm clearance around intake, supercharger and accessory components
• Pressure-test the system after repairs when appropriate
• Review the product listing for direct-fit or universal installation notes

Common Questions

What does a coolant expansion tank do?

It stores coolant volume as temperature changes and supports the cooling system recovery process when matched to the vehicle design.

Is an expansion tank the same as a supercharger tank?

Not always. A supercharged vehicle can have a separate intercooler coolant circuit with its own tank, so confirm the circuit in the listing.

Why do coolant tanks crack?

Age, heat cycles, pressure, vibration and damaged mounting points can contribute to cracks or leaks.

Can I install a universal expansion tank?

Only if its capacity, ports, cap arrangement, mounting and system requirements suit the build. Direct-fit tanks are preferred for stock-style repairs.

Do I need a new radiator cap with a new tank?

Inspect the cap and replace it if it is damaged or no longer meets the system specification. Confirm cap compatibility with the tank.

Which Subaru applications are listed?

The collection includes Moroso coolant and intercooler tank listings for specified WRX and STI applications. Check the exact year and circuit.

Can a bad expansion tank cause overheating?

A leak or loss of coolant can contribute to overheating. Inspect the entire cooling system and repair the fault promptly.

Should I pressure-test after installation?

A pressure test can help identify leaks after cooling-system work when performed with the correct tool and procedure.

Are aluminum tanks better for every vehicle?

Material alone does not guarantee fitment. Choose a tank that matches the vehicle cooling system, mounting and hose configuration.

What should I verify before ordering?

Verify vehicle fitment, cooling circuit, hose layout, cap arrangement, mounting points and whether the part is direct-fit or universal.

Why Buy Expansion Tanks from Black Ops Auto Works

Black Ops Auto Works stocks 21 Expansion Tanks SKUs with real fitment data, competitive pricing, and support from staff who build these vehicles themselves. Products are filterable by year, make, model, trim, engine, and drivetrain to confirm the correct application before ordering.

For focused shopping, browse our coolants, coolant reservoirs, radiator caps, radiators, fuel systems, surge tanks, Mishimoto parts.