GMC 2010 Tahoe, Owner'S Manual

Page: 68 / 120

Turn the DMCM coolant surge tank pressure cap
slowly counterclockwise (left) about one full turn.
Wait 30 seconds.
2. Then keep turning the DMCM coolant surge tank
pressure cap slowly, and remove it.
3. Add the pre ‐ mixed DEX ‐ COOL ™ , available at your
dealer/retailer, to the DMCM coolant surge tank
until the level reaches the FULL COLD mark.
4. Turn the ignition to ON/RUN without starting the
engine. The hybrid cooling pumps will run and any
trapped air will purge to the surge tank.
5. Add the pre ‐ mixed DEX ‐ COOL ™ , available at your
dealer/retailer, until the coolant level is maintained
at the FULL COLD mark. This should take no
longer than two minutes of hybrid cooling pump
operation.
If the level cannot be kept at the FULL COLD
level, your vehicle may need service. See your
dealer/retailer.
6. Then replace the
DMCM coolant surge
tank pressure cap.
Be sure the pressure
cap is hand-tight and
fully seated.
Notice: Using tap water, cooling system sealers or
conditioners in an attempt to stop coolant leaks can
damage the DMCM and engine cooling systems.
Never use tap water, cooling system sealers or
conditioners in your cooling system.
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