Engine Fan Noise; Power Steering Fluid - Chevrolet 2008 Tahoe Owner's Manual

Engine Fan Noise

If your 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 fan is spinning slower and the clutch is
not fully engaged. This improves fuel economy and
reduces fan noise. Under heavy vehicle loading, trailer
towing, and/or high outside temperatures, the fan speed
increases as the clutch more fully engages, so you may
hear an increase in fan noise. This is normal and should
not be mistaken as the transmission slipping or making
extra shifts. It is merely the cooling system functioning
properly. The fan will slow down when additional cooling
is not required and the clutch disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch partially
disengages.
If your vehicle has electric cooling fans, you may hear
the fans spinning at low speed during most everyday
driving. The fans may turn off if no cooling is required.
Under heavy vehicle loading, trailer towing, and/or high
outside temperatures, or if you are operating your air
conditioning system, the fans may change to high speed
and you may hear an increase in fan noise. This is normal
and indicates that the cooling system is functioning
properly. The fans will change to low speed when
additional cooling is no longer required.

Power Steering Fluid

If your vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
When to Check Power Steering Fluid
It is not necessary to regularly check power steering fluid
unless you suspect there is a leak in the system or you
hear an unusual noise. A fluid loss in this system could
indicate a problem. Have the system inspected and
repaired.
See Engine Compartment
Overview on page 5-14 for
reservoir location.
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