GMC 2003 Yukon Denali User Manual page 313

If you have to add coolant more than four times a year,
have your dealer check your cooling system.
Notice: If you use the proper coolant, you don't
have to add extra inhibitors or additives which claim
to improve the system. These can be harmful.
Checking Coolant
The coolant surge tank is
located in the engine
compartment on the
passenger's side of the
vehicle.
.
1
~
- - - l g the surge tanl- ,xessure 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
radiator are hot.
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 3-52.
See Engine Compartment Overview on page 5-12 for
more information on location.
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