2008 GMC ENVOY brake

Tire Chains
{CAUTION:
Do not use tire chains. There is not enough
clearance. Tire chains used on a vehicle
without the proper amount of clearance can
cause damage to the brakes, suspension, or
other vehicle parts. The area damaged by the
tire chains could cause you to lose control of
your vehicle and you or others may be injured in
a crash. Use another type of traction device only
if its manufacturer recommends it for use on
your vehicle and tire size combination and road
conditions. Follow that manufacturer’s
instructions. To help avoid damage to your
vehicle, drive slowly, re-adjust or remove the
device if it is contacting your vehicle, and do
not spin your wheels. If you do nd traction
devices that will t, install them on the
rear tires.
Accessory Inator
Your vehicle may have an accessory inator system.
You can inate things like basketballs and bicycle tires.
You can also use it to bring your tire pressure up to
the proper pressure. It is not designed to inate large
objects which will require more than ve minutes to
inate, such as an air mattress.
The accessory inator is
located in the rear
compartment on the
driver’s side of the vehicle
behind an access cover,
near the liftgate opening.
To remove the cover, push in on the tab to access the
inator.
You may have an air inator kit that is located in the
glove compartment. It includes a 22 ft (6.7 m) hose with
three nozzle adapters.
5-80

To use the accessory inator:
1. Attach the appropriate nozzle adapter to the end of
the hose, if required.
{CAUTION:
Inating something too much can make it
explode, and you or others could be injured.
Be sure to read the inator instructions, and
inate any object only to its recommended
pressure.
2. Attach that end of the hose to the object you wish
to inate.
3. Attach the other end of the hose to the outlet.
4. Press and release the switch to turn the air inator
on. The indicator light will remain on when the
inator is running.
The system has an internal clock to prevent the
system from overheating. The system will allow
about ve minutes of running time, then the
compressor will stop. The indicator light will then
begin to ash. When the indicator is off, the inator
can be started again by pressing the switch. If the
compressor is still hot, it may only run for a short time
before shutting off again.
5. Press and release the switch to turn the inator off.Place the inator kit tools in the pouch and store it in
its proper location. Remove the inator hose from
the outlet during loading and unloading. Load leveling
will not function with the inator hose attached to
the inator outlet. SeeElectronically Controlled Air
Suspension System on page 4-44for more information.
To reinstall the cover, line up the tabs at the back of
the cover, put it in place and latch the tabs.
A continuous ashing indicator light may also indicate a
malfunction in the air suspension system. See
Electronically Controlled Air Suspension System on
page 4-44for more information.
If a Tire Goes Flat
It is unusual for a tire to blowout while you are driving,
especially if you maintain your vehicle’s tires properly.
If air goes out of a tire, it is 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 at tire creates 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.
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A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you would
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 the
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. SeeHazard Warning Flashers on
page 3-6for more information.
{CAUTION:
Changing a tire can be dangerous. The vehicle
can slip off the jack and roll over or fall on you
or other people. You and they could be badly
injured or even killed. Find a level place to
change your tire. To help prevent the vehicle
from moving:
1. Set the parking brake rmly.
2. Put the shift lever in PARK (P).
CAUTION: (Continued)
5-82

{CAUTION:
Incorrect wheel nuts or improperly tightened
wheel nuts can cause the wheel to come loose
and even come off. This could lead to an
accident. Be sure to use the correct wheel nuts.
If you have to replace them, be sure to get
new original equipment wheel nuts. Stop
somewhere as soon as you can and have the
nuts tightened with a torque wrench to the
proper torque specication. SeeCapacities and
Specifications on page 5-120for wheel nut
torque specication.Notice:Improperly tightened wheel nuts can lead
to brake pulsation and rotor damage. To avoid
expensive brake repairs, evenly tighten the wheel
nuts in the proper sequence and to the proper torque
specication. SeeCapacities and Specifications on
page 5-120for the wheel nut torque specication.
14. Use the wrench to
tighten the wheel nuts
rmly in a crisscross
sequence as shown.
5-91

Fuses Usage
5 Driver Side High-Beam Headlamp
6 Driver Side Low-Beam Headlamp
7 Windshield Wiper
8 Active Transfer Case
9 Windshield Washer
10 Powertrain Control Module B
11 Fog Lamps
12 Stoplamp
13 Cigarette Lighter
15 Electric Adjustable Pedals
16 Truck Body Controller, Ignition 1
17 Crank
18 Airbag
19 Trailer Electric Brake
20 Cooling Fan
21 Horn
22 Ignition EFuses Usage
23 Electronic Throttle Control
24Instrument Panel Cluster, Driver
Information Center
25Automatic Shift Lock Control
System
26Transmission Control Module
Canister
27 Backup
28 Powertrain Control Module 1
29 Oxygen Sensor
30 Air Conditioning
31 Truck Body Controller 1
32 Trailer
33 Antilock Brakes (ABS)
34 Ignition A
35 Blower Motor
36 Blower
50 Passenger Side Trailer Turn
5-112

Fuses Usage
5 Driver Side High-Beam Headlamp
6 Driver Side Low-Beam Headlamp
7 Windshield Wiper
8 Active Transfer Case
9 Windshield Washer
10 Powertrain Control Module B
11 Fog Lamps
12 Stoplamp
13 Cigarette Lighter
14 Ignition Coils
15Transmission Control Module
(TCM) Canister Vent
16 Truck Body Controller, Ignition 1
17 Crank
18 Airbag
19 Trailer Electric Brake
20 Cooling Fan
21 Horn
22 Ignition E
23 Electronic Throttle ControlFuses Usage
24Instrument Panel Cluster, Driver
Information Center
25Automatic Shift Lock Control
System
26 Engine 1
27 Backup
28 Powertrain Control Module 1
29 Powertrain Control Module
30 Air Conditioning
31 Injector Bank A
32 Trailer
33 Antilock Brakes (ABS)
34 Ignition A
35 Blower Motor
36 Ignition B
50 Passenger Side Trailer Turn
51 Driver Side Trailer Turn
52 Hazard Flashers
53 Transmission
54 Oxygen Sensor Bank B
55 Oxygen Sensor Bank A
5-115

Fuses Usage
35 Transmission Control Module
36Heat Ventilation Air
Conditioning B
37 Front Parking Lamps
38 Driver Side Turn Signal
39Heat Ventilation Air
Conditioning 1
40 Truck Body Controller 4
41 Radio
42 Trailer ParkFuses Usage
43 Passenger Side Turn Signal
44 Heat Ventilation Air Conditioning
45 Rear Fog Lamps
46 Auxiliary Power 1
47 Ignition 0
48 Four-Wheel Drive
49 Blank
50 Truck Body Controller Ignition
51 Brakes
52 Truck Body Controller Run
5-119

Scheduled Maintenance
Service MaintenanceIMaintenanceII
Change engine oil and lter. SeeEngine Oil on page 5-16. Reset oil life
system. SeeEngine Oil Life System on page 5-19.An Emission Control
Service.••
Visually check for any leaks or damage.See footnote (j).••
Inspect engine air cleaner lter. If necessary, replace lter. SeeEngine Air
Cleaner/Filter on page 5-21.See footnote (k).•
Rotate tires and check ination pressures and wear. SeeTire Inspection and
Rotation on page 5-72and “Tire Wear Inspection” inAt Least Once a Month on
page 6-9.••
Inspect brake system.See footnote (a).••
Check engine coolant and windshield washer uid levels and add uid as
needed.••
Perform any needed additional services. See “Additional Required Services” in
this section.••
Inspect suspension and steering components.See footnote (b).•
Inspect engine cooling system.See footnote (c).•
Inspect wiper blades.See footnote (d).•
Inspect restraint system components.See footnote (e).•
Lubricate body components.See footnote (f).•
Check transmission uid level and add uid as needed.See footnote (g).•
6-5