Chevrolet Express 2020 Owner's Manual page 237

236 Vehicle Care
How to Add Coolant to the
Radiator
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. Never turn
the cap when the cooling system,
including the pressure cap, is hot.
Wait for the cooling system and
pressure cap to cool.
If coolant is needed, add the proper
mixture directly to the radiator, but
be sure the cooling system is cool
before this is done.
1. Remove the radiator pressure
cap when the cooling system,
including the radiator pressure
cap and upper radiator hose, is
no longer hot. Turn the
pressure cap slowly
counterclockwise until it first
stops. Do not press down while
turning the pressure cap.
If a hiss is heard, wait for that
to stop. A hiss means there is
still some pressure left.
2. Keep turning the pressure cap,
but now push down as you turn
it. Remove the pressure cap.
3. Fill the radiator with the proper
mixture, up to the base of the
filler neck. See Recommended
Fluids and Lubricants 0 315 for
more information about the
proper coolant mixture.
4. Remove the coolant recovery
tank cap and fill to the COLD
FILL mark.
5. Reinstall the cap back on the
coolant recovery tank, but
leave the radiator pressure
cap off.
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