2008 GMC ENVOY Owner's Manual

Front Turn Signal, Sidemarker and
Parking Lamps
To replace one of these bulbs:
1. Follow Steps 1 through 3 underHeadlamps on
page 5-50to access the front turn signal,
sidemarker or parking lamp.
2. Turn the bulb socket counterclockwise and remove
it from the lamp assembly.
3. Holding the socket, pull the old bulb to release it
from the socket.
4. Push the new bulb into the socket until it clicks.
5. Insert the bulb socket into the lamp assembly and
turn it clockwise to secure.
6. Reinstall the headlamp assembly by lining up the
headlamp assembly with the slots in the headlamp
retaining clips.
7. Press down on the headlamp retaining clips to
secure the headlamp assembly.
Taillamps, Turn Signal, and
Stoplamps
To replace a stoplamp/taillamp or turn signal bulb:
1. Open the liftgate. SeeLiftgate/Liftglass on
page 2-12for more information.
2. Remove the
two screws from the
taillamp assembly.
3. Pull the assembly away from the vehicle.
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4. Unclip the wiring harness (A) and remove the
three socket retaining screws (B).5. Remove the socket plate.
6. Holding the socket, pull the bulb to release it from
the socket.
7. Push the new bulb into the socket until it clicks.
8. Reinstall the socket plate and tighten the
three screws.
9. Reconnect the wiring harness.
10. Reinstall the taillamp assembly by lining up the
locator pins with the retainers in the body of the
vehicle.
11. Reinstall the two screws and tighten.
12. Close the liftgate.
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Back-Up Lamps
The back-up lamps are
located in the rear bumper.
To replace a bulb:
1. Reach behind the rear bumper and locate the bulb
socket.
2. Turn it counterclockwise to remove from the lamp
assembly.
3. Holding the socket, pull the old bulb to release it
from the socket.
4. Push in a new bulb into the bulb socket until it
clicks.
5. Reinstall the bulb socket into the lamp assembly
and turn it clockwise to secure.
License Plate Lamp
1. Remove the two screws holding the license plate
lamp lens.
2. Pull the lens away from the lamp assembly.
3. Pull the old bulb straight out from the bulb socket.
4. Install the new bulb.
5. Replace the lamp assembly lens and tighten the
screws.
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Replacement Bulbs
Exterior Lamp Bulb Number
Back-up Lamps/Rear Turn Signal
Lamp, Stoplamp, and Taillamp3157
Front Sidemarker Lamps 194
Front Turn Signal Lamps 3457
License Plate Lamp W5W
High-Beam Headlamps 9005 HB3
Low-Beam Headlamps 9006 HB4
For replacement bulbs not listed here, contact your
dealer/retailer.
Windshield Wiper Blade
Replacement
Windshield wiper blades should be inspected for wear
or cracking. SeeScheduled Maintenance on page 6-4.
Allowing the wiper blade arm to touch the windshield
when no wiper blade is installed could damage the
windshield. Any damage that occurs would notbe covered by your warranty. Do not allow the wiper
blade arm to touch the windshield.
1. To remove the old wiper blades, lift the wiper arm
until it locks into a vertical position.
A. Blade Assembly
B. Arm Assembly
C. Locking TabD. Blade Pivot
E. Hook Slot
F. Arm Hook
2. Press down on the blade assembly pivot locking
tab. Pull down on the blade assembly to release it
from the wiper arm hook.
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3. Remove the insert from the blade assembly. The
insert has two notches at one end that are locked
by the bottom claws of the blade assembly. At the
notched end, pull the insert from the blade assembly.
4. To install the new wiper insert, slide the insert (D),
notched end last, into the end with two blade
claws (A). Slide the insert all the way through the
blade claws at the opposite end (B). The plastic
caps (C) will be forced off as the insert is fully
inserted.
5. Be sure that the notches are locked by the bottom
claws. Make sure that all other claws are properly
locked on both sides of the insert slots.A. Claw in Notch
B. Correct Installation
C. Incorrect Installation
6. Put the blade assembly pivot in the wiper arm hook.
Pull up until the pivot locking tab locks in the
hook slot.
7. Carefully lower the wiper arm and blade assembly
onto the windshield.
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Backglass Wiper Blade Replacement
1. Lift the wiper blade assembly up and out of the
park rest position.
2. Pull the wiper blade assembly away from the
backglass. The backglass wiper blade will not
lock in a vertical position, so care should be used
when pulling it away from the vehicle.3. Rotate the wiper blade assembly, and pull it off of
the wiper arm. Hold the wiper arm in position and
push the blade away from the wiper arm.
4. Replace the wiper blade.
5. Return the wiper blade assembly to the park rest
position.
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Tires
Your new vehicle comes with high-quality tires
made by a leading tire manufacturer. If you ever
have questions about your tire warranty and where
to obtain service, see your vehicle Warranty
booklet for details.
{CAUTION:
Poorly maintained and improperly
used tires are dangerous.
Overloading your tires can cause
overheating as a result of too much
exing. You could have an air-out and
a serious accident. SeeLoading Your
Vehicle on page 4-34.
CAUTION: (Continued)
CAUTION: (Continued)

Underinated tires pose the same
danger as overloaded tires. The
resulting accident could cause serious
injury. Check all tires frequently to
maintain the recommended pressure.
Tire pressure should be checked when
your tires are cold. SeeInflation - Tire
Pressure on page 5-64.
Overinated tires are more likely
to be cut, punctured, or broken by
a sudden impact — such as when
you hit a pothole. Keep tires at the
recommended pressure.
Worn, old tires can cause accidents.
If your tread is badly worn, or if
your tires have been damaged,
replace them.
SeeHigh-Speed Operation on page 5-66
for ination pressure adjustment for high
speed driving.
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Low-Prole Performance Tire
If your vehicle has P255/50R20 size tires, they are
classied as low-prole performance tires. These
tires are designed for very responsive driving on
wet or dry pavement. You may also notice more
road noise with low-prole performance tires and
that they tend to wear faster.
Notice:If your vehicle has low-prole tires,
they are more susceptible to damage from road
hazards or curb impact than standard prole
tires. Tire and/or wheel assembly damage can
occur when coming into contact with road
hazards like, potholes, or sharp edged objects,
or when sliding into a curb. Your vehicle
warranty does not cover this type of damage.
Keep tires set to the correct ination pressure
and, when possible avoid contact with curbs,
potholes, and other road hazards.
Tire Sidewall Labeling
Useful information about a tire is molded into the
sidewall. The following illustration is an example
of a typical P-Metric tire sidewall.
(A) Tire Size
:The tire size code is a combination
of letters and numbers used to dene a particular
tire’s width, height, aspect ratio, construction type,
and service description. See the “Tire Size”
illustration later in this section for more detail.
Passenger (P-Metric) Tire
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