2003 GMC ENVOY tow

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
®ller neck may be lower. If the level is lower, add
more of the proper DEX-COOL
žcoolant mixture
through the ®ller neck until the level reaches
the base of the ®ller neck.
8. Then replace the pressure cap. At any time during
this procedure if coolant begins to ¯ow out of the
®ller neck, reinstall the pressure cap. Be sure
the pressure cap is hand-tight.
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. 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.
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The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The ®rst rotation
is the most important. See ªPart A: Scheduled
Maintenance Services,º in Section 6, for scheduled
rotation intervals.
When rotating your tires, always use the correct rotation
pattern shown here.
After the tires have been rotated, adjust the front and
rear in¯ation pressures as shown on the
Certi®cation/Tire label. Make certain that all wheel nuts
are properly tightened. See ªWheel Nut Torqueº
under
Capacities and Speci®cations on page 5-102.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after a time. The wheel could
come off and cause an accident. When you
change a wheel, remove any rust or dirt from
places where the wheel attaches to the vehicle.
In an emergency, you can use a cloth or a
paper towel to do this; but be sure to use a
scraper or wire brush later, if you need to, to
get all the rust or dirt off. See ªChanging a Flat
Tireº in the Index.
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If a Tire Goes Flat
It's unusual for a tire to ªblowoutº 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 ªblowout,º here are a few
tips about what to expect and what to do:
If a front tire fails, the ¯at tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel ®rmly.
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.{CAUTION:
Lifting a vehicle and getting under it to do
maintenance or repairs is dangerous without
the appropriate safety equipment and training.
The jack provided with your vehicle is
designed only for changing a ¯at tire. If it is
used for anything else, you or others could be
badly injured or killed if the vehicle slips off
the jack. Use the jack provided with your
vehicle only for changing a ¯at tire.
If a tire goes ¯at, the next part shows how to use your
jacking equipment to change a ¯at tire safely.
Changing a Flat Tire
If a tire goes ¯at, avoid further tire and wheel damage
by driving slowly to a level place. Turn on your
hazard warning ¯ashers.
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The tools you'll be using include the wheel wrench (A),
tire blocks (B), extension(s) (socket end) (C), handle
(jack end) (D), and jack (E).
The following instructions explain how to remove the
spare tire mounted underneath your vehicle.
Notice:Never remove or restow a tire from/to a
storage position under the vehicle while the vehicle
is supported by a jack. Always tighten the tire
fully against the underside of the vehicle when
restowing.1. To remove the underbody-mounted spare, insert
the socket end of the extension on a 45É angle
downward into the hoist drive shaft hole. It is
exposed when the rear gate is open and is just
above the rear bumper. Be sure the socket end of
the extension connects into the hoist shaft.
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2. If it is not visible, proceed to Step 6.
If visible, ®rst try to tighten the cable by turning the
wheel wrench clockwise until you hear two clicks
or feel it skip twice. You cannot overtighten
the cable.
3. Loosen the cable by turning the wheel wrench
counterclockwise three or four turns.
4. Repeat this procedure at least two times.
If the spare tire lowers to the ground, continue with
Step 2 of ªRemoving the Spare Tire and Toolsº
earlier in this section.
5. Turn the wrench counterclockwise until
approximately 6 inches (15 cm) of cable is exposed.
6. Attach the jack handle, extension and the wheel
wrench to the jack and place it under the vehicle
towards the front of the rear bumper. Position
the center lift point of the jack under the center of
the spare tire.
7. Turn the wrench clockwise to raise the jack until it
lifts the end ®tting.
8. Continue raising the jack until the spare tire stops
moving upward and is held ®rmly in place. The
secondary latch has released and the spare tire is
balancing on the jack.
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5. Raise the vehicle by turning the jack handle
clockwise. Raise the vehicle far enough off the
ground so there is enough room for the spare tire
to ®t.
6. Remove all the wheel nuts and take off the ¯at tire.7. Remove any rust or dirt
from the wheel bolts,
mounting surfaces
and spare wheel.
{CAUTION:
Rust or dirt on the wheel, or on the parts to
which it is fastened, can make the wheel nuts
become loose after a time. The wheel could
come off and cause an accident. When you
change a wheel, remove any rust or dirt from
the places where the wheel attaches to the
vehicle. In an emergency, you can use a cloth
or a paper towel to do this; but be sure to use
a scraper or wire brush later, if you need to, to
get all the rust or dirt off.
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{CAUTION:
Never use oil or grease on studs or nuts. If
you do, the nuts might come loose. Your wheel
could fall off, causing a serious accident.
8. Place the spare on the wheel mounting surface.
9. Put the nuts on by
hand. Make sure the
rounded end is
toward the wheel
10. Tighten each nut by hand until the wheel is held
against the hub. If a nut can't be turned by hand,
use the wheel wrench and see your dealer as soon
as possible.11. Lower the vehicle by turning the jack handle
counterclockwise. Lower the jack completely.
5-75

Storing a Flat or Spare Tire and Tools
{CAUTION:
Storing a jack, a tire, or other equipment in the
passenger compartment of the vehicle could
cause injury. In a sudden stop or collision,
loose equipment could strike someone. Store
all these in the proper place.
{CAUTION:
The underbody-mounted spare tire needs to be
stored with the valve stem pointing up. If the
spare tire is stored with the valve stem
pointing downward, its secondary latch won't
work properly and the spare tire could loosen
and suddenly fall from your vehicle.
CAUTION: (Continued)
CAUTION: (Continued)
If this happened when your vehicle was being
driven, the tire might contact a person or
another vehicle, causing injury and, of course,
damage to itself as well. Be sure the
underbody-mounted spare tire is stored with
its valve stem pointing up.
Notice:An aluminum wheel with a ¯at tire should
always be stored under the vehicle with the
hoist. However, storing it that way for an extended
period could damage the wheel. To avoid this,
always stow the wheel properly with the valve stem
pointing up and have the wheel repaired as soon
as possible.
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