GMC T-Series 2007, Owner'S Manual, Page: 217 / 356

What to Use
Use a mixture of one-half clean, drinkable water
and one-half DEX-COOL
®
coolant which will
not damage aluminum parts. If you use this coolant
mixture, you do not need to add anything else.
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CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can
boil before the proper coolant mixture will.
Your vehicle’s coolant warning system is
set for the proper coolant mixture. With
plain water or the wrong mixture, your
engine could get too hot but you would
not get the overheat warning. Your engine
could catch fire and you or others could
be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®
coolant.
Notice: If you use an improper coolant
mixture, your engine could overheat and be
badly damaged. The repair cost would not be
covered by your warranty. Too much water
in the mixture can freeze and crack the engine,
radiator, heater core, and other parts.
If you have to add coolant more than four times a
year, have your dealer/retailer check your
cooling system.
Notice: If you use extra inhibitors and/or
additives in your vehicle’s cooling system,
you could damage your vehicle. Use only the
proper mixture of the engine coolant listed
in this manual for the cooling system. See Part
C: Recommended Fluids and Lubricants on
page 321 for more information.
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