GMC Terrain 2018-present Fuel System Specifications

The 2018-Present GMC Terrain is compatible with regular unleaded gasoline with an octane rating of 87 or higher. For optimal performance and fuel efficiency, it is recommended to avoid using gasoline with ethanol blends higher than 15% (E15). Diesel or other alternative fuels are not supported. Always refer to the owner's manual for specific fuel requirements and compatibility.

The GMC Terrain's fuel system requires regular maintenance, including fuel filter replacement every 30,000 miles, fuel injector cleaning every 15,000 miles, and periodic inspection of the fuel lines and tank for leaks or damage. Using high-quality fuel and fuel system cleaners can help maintain performance. Refer to the maintenance schedule in the owner's manual for detailed intervals and procedures.

To replace the fuel filter in a GMC Terrain, first, locate the fuel filter near the fuel tank. Relieve the fuel system pressure by removing the fuel pump fuse and running the engine until it stalls. Disconnect the negative battery terminal. Remove the fuel lines and mounting bolts, then replace the old filter with a new one. Reconnect the fuel lines and battery terminal, and test for leaks.

If your GMC Terrain has fuel system issues, such as poor fuel economy, engine misfires, or difficulty starting, first check the fuel filter and fuel pump for blockages or failures. Inspect fuel lines for leaks or damage. Use a diagnostic scanner to check for error codes related to the fuel system. If problems persist, consult a certified technician for professional diagnosis and repair.

To optimize fuel efficiency in your GMC Terrain, maintain proper tire pressure, use high-quality fuel, and avoid excessive idling. Regularly replace the air filter and fuel filter, and ensure the engine is properly tuned. Drive at consistent speeds and avoid rapid acceleration or braking. Utilize the Terrain's Eco mode feature to reduce fuel consumption during city driving.