GMC 2010 Canyon Crew Cab Owner's Manual page 310

6. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fan.
6-34
7. By this time, the coolant level inside the radiator
filler neck might be lower. If the level is lower, add
more of the proper DEX-COOL
through the filler neck until the level reaches
the base of the filler neck.
8. Then replace the pressure cap.
At any time during this procedure if coolant begins to
flow out of the filler neck, reinstall the pressure cap.
Notice: If the pressure cap is not tightly installed,
coolant loss and possible engine damage may
occur. Be sure the cap is properly and tightly
secured.
®
coolant mixture