Specifications

Engine Coolant
If your vehicle has the DURAMAX
®
Diesel engine, see
the DURAMAX
®
Diesel manual for more information.
The cooling system in your vehicle is filled with
DEX-COOL
®
engine coolant. This coolant is designed
to remain in your vehicle for five years or 150,000 miles
(240 000 km), whichever occurs first, if you add only
DEX-COOL
®
extended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem
with engine overheating, see Engine Overheating on
page 5-32.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
®
coolant will:
• Give freezing protection down to −34°F (−37°C).
• Give boiling protection up to 265°F (129°C).
• Protect against rust and corrosion.
• Help keep the proper engine temperature.
• Let the warning lights and gages work as they
should.
Notice: Using coolant other than DEX-COOL
®
may
cause premature engine, heater core, or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at the first maintenance
service after each 30,000 miles (50 000 km) or
24 months, whichever occurs first. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®
(silicate-free) coolant in your vehicle.
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