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 2018-2026 Owners Manual: Exhaust Fluid Quality Poor


    Use only exhaust fluid that is GM approved, or fluid containing the API certified or ISO 22241 label. All DEF has an expiration date. If the system detects poor quality, or contaminated or diluted DEF, the DIC message EXHAUST FLUID QUALITY POOR - SEE OWNERS MANUAL NOW – 160 KM (99 MI) UNTIL 104 KM/H (65 MPH) MAX SPEED displays...

    GMC Terrain 2018-2026 Owners Manual: Alerting the Driver


    If ACC is engaged, driver action may be required when ACC cannot apply sufficient braking because of approaching a vehicle too rapidly. When this condition occurs, six red lights will flash on the windshield. Either eight beeps will sound from the front, or both sides of the Safety Alert Seat will pulse five times...

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