Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-13336155) - 2020 - CRC - 5/6/19
Vehicle Care
77
Turn the pressure cap slowly
counterclockwise about one full
turn. 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
slowly, and remove it.
3. Slowly fill the coolant surge
tank. Do not let the coolant
level go above the indicated
mark in the tank until after the
engine comes to operating
temperature in Step 4.
4. With the coolant surge tank
pressure cap off, start the
engine and let it run until the
engine coolant temperature
gauge indicates approximately
90 °C (195 °F).
By this time, the coolant level
inside the coolant surge tank
may be lower. If the level is
lower, slowly add more of the
proper mixture to the coolant
surge tank until it reaches the
indicated mark.
5. Re-install the pressure cap.
Be sure the pressure cap is
hand-tight and fully seated.
6. Verify coolant level after the
engine is shut off and the
coolant is cold. If necessary,
repeat Steps 1
–
6.
If the coolant level is still low after
having followed these steps twice,
have the coolant system checked by
a certified technician at the dealer
for a possible leak.
Caution
If the pressure cap is not tightly
installed, coolant loss and engine
damage may occur. Be sure the
cap is properly and tightly
secured.
Engine Overheating
There is an engine coolant
temperature gauge on the
instrument cluster. See the owner
’
s
manual.
If Steam Is Coming from the
Engine Compartment
{
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.
Caution
Do not run the engine if there is a
leak in the engine cooling system.
This can cause a loss of all
coolant and can damage the
system and vehicle. Have any
leaks fixed right away.
