GMC 2015 Savana Owner's Manual page 250

3. Fill the radiator with the proper
DEX-COOL coolant mixture, up
to the base of the filler neck.
See Recommended Fluids and
Lubricants on page 11-10 for
more information about the
proper coolant mixture.
4. Fill the coolant recovery tank to
the COLD FILL mark.
5. Reinstall the cap back on the
coolant recovery tank, but leave
the radiator pressure cap off.
Vehicle Care
6. Start the engine and let it run
until the upper radiator hose can
be felt getting hot. Watch out for
the engine cooling fan.
7. By this time, the coolant level
inside the radiator filler neck
may be lower. If the level is
lower, add more of the proper
DEX-COOL coolant mixture
through the filler neck until the
level reaches the base of the
filler neck.
10-17