3. Fill the radiator with the proper DEX-COOL®
coolant mixture, up to the base of thefiller
neck. SeeEngine Coolant on page 5-25for more
information about the proper coolant mixture.4. Thenfill the coolant recovery tank to ADD mark.
5. Put the cap back on the coolant recovery tank,
but leave the radiator pressure cap off.
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2003 - Sonoma OM
6. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fan.
7. By this time, the coolant level inside the radiator
filler neck may be lower. If the level is lower, add
more of the proper DEX-COOL
®coolant mixture
through thefiller neck until the level reaches
the base of thefiller neck.8. Then replace the pressure cap. At any time during
this procedure if coolant begins toflow out of the
filler neck, reinstall the pressure cap. Be sure
the arrow on the pressure cap lines up like this.Engine Fan Noise
This vehicle has a clutched engine cooling fan. When
the clutch is engaged, the fan spins faster to provide
more air to cool the engine. In most everyday driving
conditions, the clutch is not engaged. This improves fuel
economy and reduces fan noise. Under heavy vehicle
loading, trailer towing and/or high outside temperatures,
the fan speed increases when the clutch engages.
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2003 - Sonoma OM