GMC Terrain: Cooling System / Checking Coolant

The vehicle must be on a level surface when checking the coolant level.

GMC Terrain. Checking Coolant

Check to see if coolant is visible in the coolant surge tank. If the coolant inside the coolant surge tank is boiling, do not do anything else until it cools down. If coolant is visible but the coolant level mark is not visible, add a 50/50 mixture of clean, drinkable water and DEX-COOL coolant at the coolant surge tank to the top rib on the middle of the tank, but be sure the cooling system is cool before this is done. See Engine Overheating.

The coolant surge tank is located in the engine compartment on the driver side of the vehicle. See Engine Compartment Overview.

    What to Use

    Warning Plain water, or other liquids such as alcohol, can boil before the proper coolant mixture will. With plain water or the wrong mixture, the engine could get too hot but there would not be an overheat warning...

    How to Add Coolant to the Coolant Surge Tank

    Warning Steam and scalding liquids from a hot cooling system are under pressure. Turning the pressure cap, even a little, can cause them to come out at high speed and you could be burned...

    Other information:

    GMC Terrain 2018-2025 Owners Manual: Cruise Control. System Operation


    The cruise control lets the vehicle maintain a speed of about 40 km/h (25 mph) or more without keeping your foot on the accelerator. Cruise control does not work at speeds below 40 km/h (25 mph). Warning Cruise control can be dangerous where you cannot drive safely at a steady speed...

    GMC Terrain 2018-2025 Owners Manual: Car Wash Mode


    This vehicle includes a Car Wash Mode that allows the vehicle to remain in N (Neutral) for use in automatic car washes. Car Wash Mode is not to be used for vehicle towing. If the vehicle needs to be towed, see Towing the Vehicle Caution The vehicle is not designed to stay in N (Neutral) for extended periods of time...

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