GMC 1998 Yukon - If a Tire Goes Flat; Engine Fan Noise; Changing a Flat Tire

Engine Fan Noise
If a Tire Goes Flat
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 disengages.
It’s unusual for
a tire to “blow out” while you’re driving,
especially
if you maintain your tires properly. If air goes
out of a tire, it’s much more likely to leak out slowly.
But if you should ever have a “blowout,” here are a few
tips about what to expect and what
to do:
If a front tire fails, the flat tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel firmly.
Steer to maintain lane position, and then gently brake to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you’d use
in a
skid.
In any rear blowout, remove your foot from the
accelerator pedal. Get the vehicle under control by
steering the way you want the vehicle to go.
It may be
very bumpy and noisy, but you can still steer. Gently
brake to
a stop -- well off the road if possible.
If a tire goes flat, the next part shows how to use your
-jacking equipment
to change a flat tire safely.
Changing a Flat Tire
If a tire goes flat, avoid further tire and wheel damage
by driving slowly to a level place. Turn on your hazard
warning Flashers.
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