GMC CHEVROLET Silverado 6500HD 2019 Owner's Manual page 303

302 Vehicle Care
2. Coolant Surge Tank
Pressure Cap
3. Engine Cooling Fan (Out
of View)
Warning
Do not touch heater or radiator
hoses, or other engine parts.
They can be very hot and can
burn you. Do not run the engine if
there is a leak; all coolant could
leak out. That could cause an
engine fire and can burn you. Fix
any leak before driving the
vehicle.
Engine Coolant
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
(Continued)
Warning (Continued)
warning. The engine could catch
fire and you or others could be
burned.
The cooling system in the vehicle is
filled with DEX-COOL engine
coolant mixture.
See Recommended Fluids and
Lubricants 0 398 and Maintenance
Schedule 0 361.
The following explains the cooling
system and how to add coolant
when it is low. If there is a problem
with engine overheating, see Engine
Overheating 0 305.
A 50/50 mixture of clean, drinkable
water and DEX-COOL coolant will:
Give freezing protection down to
37 °C ( 34 °F).
Give boiling protection up to 129
°C (265 °F).
Protect against rust and
corrosion.
Help keep the proper engine
temperature.
Let the warning lights and
gauges work as they should.
What to Use
Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
coolant which will not damage
aluminum parts. If using this
mixture, nothing else needs to be
added.
If coolant has to be added more
than four times a year, have your
dealer check the vehicle cooling
system.
Caution
Do not use anything other than a
mix of DEX-COOL coolant that
meets GM Standard
GMW3420 and clean, drinkable
water. Anything else can cause
damage to the engine cooling
system and the vehicle, which
would not be covered by the
vehicle warranty.