CHEVROLET 2009 Suburban - Manual (Page 431)

Checking Coolant
The vehicle must be on a level surface when checking
the coolant level.
Check to see if coolant is visible in the coolant surge tank.
If the coolant inside the coolant surge tank is boiling, do
not do anything else until it cools down. If coolant is
visible but the coolant level is not at or above the FULL
COLD mark, add a 50/50 mixture of clean, drinkable
water and DEX-COOL
® coolant at the coolant surge tank,
but be sure the cooling system is cool before this is done.
The coolant surge tank is located in the engine
compartment on the passenger side of the vehicle.
See Engine Compartment Overview on page 5-14 for
more information on location.
The coolant level should be at or above the FULL COLD
mark. If it is not, you may have a leak in the cooling
system.
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