Chevrolet 2003 Silverado 1500 Pickup Owner's Manual page 410

Turning the surge tank press~~re
cap
when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. Never turn the surge tank pressure
cap
-
even a little
-
when the engine and
The vehicle must be on a level surface. When your
engine is cold, the coolant level should be at the FULL
COLD mark.
If the LOW COOLANT LEVEL message comes on and
stays on, it means you're low on engine coolant.
See "Low Coolant Level" under DIC Warnings and
Messages on page 3-60.
Adding Coolant
If you need more coolant, add the proper DEX-COOL@
coolant mixture at the surge tank, but only when the
engine is cool.
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol,
and it will burn if the engine parts are hot
enough. Don't spill coolant on a hot engine.
When replacing the pressure cap, make sure it is
hand-tight.
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