Selecting the correct 2018 Subaru Forester coolant type is essential for protecting the heart of your vehicle, the horizontally-opposed Subaru BOXER engine. This specific model year requires a precise formulation to maintain optimal thermal transfer and prevent corrosion within the intricate aluminum components. Using an incorrect mixture can lead to overheating, reduced efficiency, and potentially costly repairs down the line, making this a critical maintenance item for any Forester owner.
Understanding the 2018 Forester Cooling System Requirements
The 2018 model year Subaru Forester utilizes a modern, long-life cooling system designed for durability. Subaru specifically engineered this system to work with a specialized coolant that meets or exceeds the standards set by the manufacturer. The system is pressurized, which elevates the boiling point of the liquid, allowing the engine to run efficiently even under heavy loads or extreme ambient temperatures. Knowing the exact specifications ensures the longevity of this vital system.
Subaru's Official Coolant Specification
For the 2018 Forester, Subaru mandates the use of Subaru Blue Coolant Type A or an equivalent that meets the Subaru WSO-025G standard. This is a pre-diluted, ready-to-use formula that comes in a distinctive blue color. It is a silicate-free, organic acid technology (OAT) coolant, which provides superior protection for the aluminum alloys and copper/ brass components found in the radiator and heater core compared to traditional green coolants.
Key Features of Subaru Blue Coolant
Specifically formulated for Subaru BOXER engines and their unique metallurgy.
Provides excellent rust inhibition and anti-wear protection for the water pump.
Features a high boiling point to prevent overheating during summer driving.
Offers superior freeze protection to prevent engine block damage in winter.
Long service life, reducing the frequency of maintenance intervals.
Consequences of Using the Wrong Coolant While generic green coolants are widely available, they are incompatible with the 2018 Forester’s cooling system. Mixing incompatible coolants can cause the chemical additives to break down, leading to the formation of sludge. This sludge can clog narrow passages in the radiator and heater core, drastically reducing cooling efficiency and potentially causing permanent damage to the engine block or head gasket. Maintenance and Refill Procedures
While generic green coolants are widely available, they are incompatible with the 2018 Forester’s cooling system. Mixing incompatible coolants can cause the chemical additives to break down, leading to the formation of sludge. This sludge can clog narrow passages in the radiator and heater core, drastically reducing cooling efficiency and potentially causing permanent damage to the engine block or head gasket.
When performing a coolant flush or top-off on your 2018 Forester, it is crucial to follow Subaru’s procedures. The system typically holds around 9.4 quarts of coolant, but always verify the exact amount for your specific configuration. Never top off with plain water, as this dilutes the critical inhibitors and compromises the system’s integrity. Always use the pre-diluted Subaru Blue Coolant to maintain the proper concentration of 50% coolant and 50% water.
Where to Source the Correct Coolant
You have several reliable options to acquire the correct 2018 Subaru Forester coolant type. The most straightforward method is to visit your local Subaru dealership, where they can provide the genuine Subaru Blue Coolant and perform a professional flush. Alternatively, many quality automotive parts stores carry the genuine Subaru formula or reputable aftermarket equivalents that explicitly state compatibility with the Subaru WSO-025G standard. Ensure the product is pre-diluted and bright blue in color before purchasing.
Final Recommendations for Longevity
Adhering to the Subaru-recommended maintenance schedule is the best way to ensure your cooling system performs flawlessly for the life of the vehicle. Replacing the coolant per the guidelines in your owner’s manual, typically every 100,000 miles or 10 years, depending on driving conditions, is vital. By consistently using the correct 2018 Subaru Forester coolant type, you safeguard one of the most reliable and adventurous vehicles on the road against the stresses of daily driving.
