GMC Terrain: Cooling System / Checking Coolant
GMC Terrain 2018-2026 Owners Manual / Vehicle Care / Vehicle Checks / Cooling System / Checking Coolant
The vehicle must be on a level surface when checking the coolant level.
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
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