GMC 2002 Yukon Denali Owner's Manual page 272

If there seems to be no leak, start the engine again.
The engine cooling fan speed should increase when idle
speed is doubled by pushing the accelerator pedal down.
If it doesn't, your vehicle needs service. Turn off
the engine.
NOTICE:
Engine damage from running your engine
without coolant isn't covered by your warranty.
See "Overheated Engine Protection Operating
Mode" in the Index.
NOTICE:
When adding coolant, it is important that you
R
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use only DEX COOL (silicate
If coolant other than DEX
the system, premature engine, heater core or
radiator corrosion may result. In addition, the
engine coolant will require change sooner
30,000 miles (50 000 km) or 24 months,
whichever occurs first. Damage caused by the
use of coolant other than DEX
covered by your new vehicle warranty.
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free) coolant.
-
COOL is added to
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at
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-
COOL is not
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