2008 GMC ENVOY DENALI fuel pressure

UTQGS (Uniform Tire Quality Grading
Standards):A tire information system that
provides consumers with ratings for a tire’s
traction, temperature, and treadwear. Ratings
are determined by tire manufacturers using
government testing procedures. The ratings are
molded into the sidewall of the tire. SeeUniform
Tire Quality Grading on page 5-77.
Vehicle Capacity Weight
:The number of
designated seating positions multiplied by
150 lbs (68 kg) plus the rated cargo load.
SeeLoading Your Vehicle on page 4-34.
Vehicle Maximum Load on the Tire
:Load on
an individual tire due to curb weight, accessory
weight, occupant weight, and cargo weight.
Vehicle Placard
:A label permanently attached to
a vehicle showing the vehicle’s capacity weight
and the original equipment tire size and
recommended ination pressure. See “Tire and
Loading Information Label” underLoading
Your Vehicle on page 4-34.
Ination - Tire Pressure
Tires need the correct amount of air pressure to
operate effectively.
Notice:Do not let anyone tell you that
under-ination or over-ination is all right.
It is not. If your tires do not have enough air
(under-ination), you can get the following:
Too much exing
Too much heat
Tire overloading
Premature or irregular wear
Poor handling
Reduced fuel economy
If your tires have too much air (over-ination),
you can get the following:
Unusual wear
Poor handling
Rough ride
Needless damage from road hazards
5-64

If your vehicle has P255/50R20 104V size tires installed
on the rear axle, they will require ination pressure
adjustment when driving your vehicle at speeds above
99 mph (160 km/h). Set the cold ination pressure, for
the rear tires only, to the maximum ination pressure
shown on the tire sidewall, or 38 psi (262 kPa), whichever
is lower. See the example following. When you end this
high-speed driving, return the tires to the cold tire ination
pressure shown on the Tire and Loading Information
label. SeeLoading Your Vehicle on page 4-34.
Example:
You will nd the maximum load and ination pressure
molded on the tire’s sidewall, in small letters, near
the rim ange. It will read something like this: Maximum
load 690 kg (1521 lbs) 300 kPa (44 psi) Max. Press.
For this example, you would set the ination pressure for
high-speed driving at 38 psi (262 kPa).
The ination pressure for the front tires should be set to
the cold tire ination pressure shown on the Tire and
Loading Information label.
Racing or other competitive driving may affect the
warranty coverage of your vehicle. See your warranty
booklet for more information.Tire Pressure Monitor System
The Tire Pressure Monitor System (TPMS) uses radio
and sensor technology to check tire pressure levels. The
TPMS sensors monitor the air pressure in your vehicle’s
tires and transmit tire pressure readings to a receiver
located in the vehicle.
Each tire, including the spare (if provided), should be
checked monthly when cold and inated to the ination
pressure recommended by the vehicle manufacturer
on the vehicle placard or tire ination pressure label.
(If your vehicle has tires of a different size than the
size indicated on the vehicle placard or tire ination
pressure label, you should determine the proper
tire ination pressure for those tires.)
As an added safety feature, your vehicle has been
equipped with a tire pressure monitoring system (TPMS)
that illuminates a low tire pressure telltale when one or
more of your tires is signicantly under-inated.
Accordingly, when the low tire pressure telltale
illuminates, you should stop and check your tires as
soon as possible, and inate them to the proper
pressure. Driving on a signicantly under-inated tire
causes the tire to overheat and can lead to tire failure.
Under-ination also reduces fuel efficiency and tire
tread life, and may affect the vehicle’s handling and
stopping ability.
5-67

(e)Make sure the safety belt reminder light and safety
belt assemblies are working properly. Look for any
other loose or damaged safety belt system parts. If you
see anything that might keep a safety belt system
from doing its job, have it repaired. Have any torn or
frayed safety belts replaced. Also see Checking
the Restraint Systems on page 1-68.
(f)Lubricate all key lock cylinders, hood latch assembly,
secondary latch, pivots, spring anchor, release pawl,
rear compartment hinges, outer liftgate handle pivot
points, rear door detent link, roller mechanism, liftgate
handle pivot points, latch bolt, fuel door hinge, cargo
door hinge, locks, and folding seat hardware. More
frequent lubrication may be required when exposed to a
corrosive environment. Applying silicone grease on
weatherstrips with a clean cloth will make them
last longer, seal better, and not stick or squeak.
(g)Inspect hoses for cracks, chafing, leaks, kinks, and
proper installation.(h)Change automatic transmission fluid and filter if the
vehicle is mainly driven under one or more of these
conditions:
In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police, or delivery
service.
(i)Drain, flush, and refill cooling system. This service
can be complex; you should have your dealer/retailer
perform this service. See Engine Coolant on page 5-26
for what to use. Inspect hoses. Clean radiator,
condenser, pressure cap, and filler neck. Pressure test
the cooling system and pressure cap.
(j)A fluid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired and
the fluid level checked. Add fluid if needed.
(k)If you drive regularly under dusty conditions, inspect
the filter at each engine oil change.
(l)Visually inspect belt for fraying, excessive cracks, or
obvious damage. Replace belt if necessary.
6-8

Owner Checks and Services
These owner checks and services should be performed
at the intervals specied to help ensure the safety,
dependability, and emission control performance of your
vehicle. Your dealer/retailer can assist you with these
checks and services.
Be sure any necessary repairs are completed at once.
Whenever any uids or lubricants are added to your
vehicle, make sure they are the proper ones, as shown
inRecommended Fluids and Lubricants on page 6-12.
At Each Fuel Fill
It is important to perform these underhood checks at
each fuel fill.
Engine Oil Level Check
Notice:It is important to check the engine oil
regularly and keep it at the proper level. Failure to
keep the engine oil at the proper level can cause
damage to the engine not covered by your warranty.
Check the engine oil level and add the proper oil if
necessary. SeeEngine Oil on page 5-16.
Engine Coolant Level Check
Check the engine coolant level and add DEX-COOL®
coolant mixture if necessary. SeeEngine Coolant
on page 5-26.
Windshield Washer Fluid Level Check
Check the windshield washer uid level in the windshield
washer uid reservoir and add the proper uid if
necessary.
At Least Once a Month
Tire Ination Check
Inspect your vehicle’s tires and make sure they are
inated to the correct pressures. Do not forget to
check the spare tire. SeeInflation - Tire Pressure on
page 5-64. Check to make sure the spare tire is stored
securely. SeeChanging a Flat Tire on page 5-82.
Tire Wear Inspection
Tire rotation may be required for high mileage highway
drivers prior to the Engine Oil Life System service
notication. Check the tires for wear and, if necessary,
rotate the tires. SeeTire Inspection and Rotation on
page 5-72.
6-9

Fuel (cont.)
Gasoline Octane........................................... 5-6
Gasoline Specications.................................. 5-6
Low Warning Light.......................................3-49
Running Out of...........................................2-38
Fuses
Engine Compartment Fuse Block.................5-110
Fuses and Circuit Breakers.........................5-110
Rear Underseat Fuse Block.........................5-116
Windshield Wiper.......................................5-109
G
Gage
Check Gages Warning Light..........................3-47
Engine Coolant Temperature.........................3-40
Fuel..........................................................3-48
Oil Pressure...............................................3-44
Speedometer..............................................3-32
Tachometer.................................................3-32
Voltmeter Gage...........................................3-37
Garage Door Opener.......................................2-52
Gasoline
Octane........................................................ 5-6
Specications............................................... 5-6
Gate Ajar Light...............................................3-48
Glove Box.....................................................2-57
GM Mobility Reimbursement Program.................. 7-7
H
Hazard Warning Flashers................................... 3-6
Head Restraints..............................................1-10
Headlamp
Aiming.......................................................5-49
Headlamps............................................3-14, 5-50
Bulb Replacement.......................................5-49
Daytime Running Lamps...............................3-15
Electrical System.......................................5-109
Flash-to-Pass............................................... 3-8
Front Turn Signal, Sidemarker and
Parking Lamps.........................................5-51
Halogen Bulbs............................................5-49
High/Low Beam Changer................................ 3-8
On Reminder..............................................3-15
Washer......................................................3-11
Heated Seats................................................... 1-4
Heater...........................................................3-21
Heater...........................................................3-23
Highbeam On Light.........................................3-47
High-Speed Operation, Tires.............................5-66
Highway Hypnosis...........................................4-28
Hill and Mountain Roads..................................4-29
Hood
Checking Things Under................................5-10
Release.....................................................5-11
Horn............................................................... 3-6
How to Wear Safety Belts Properly...................1-18
6

I
Ignition Positions.............................................2-21
Infants and Young Children, Restraints...............1-35
Ination - Tire Pressure...................................5-64
Instrument Panel
Overview..................................................... 3-4
Instrument Panel (I/P)
Brightness..................................................3-17
Cluster.......................................................3-31
J
Jump Starting.................................................5-42
K
Keyless Entry System....................................... 2-4
Keys............................................................... 2-3
L
Labeling, Tire Sidewall.....................................5-58
Lamps
Dome........................................................3-17
Dome Lamp Override...................................3-17
Reading.....................................................3-18
Lap-Shoulder Belt...........................................1-26LATCH System
Child Restraints...........................................1-41
License Plate Lamps.......................................5-53
Liftgate/Liftglass..............................................2-12
Liftglass/Liftgate..............................................2-12
Light
Airbag Readiness........................................3-33
Antilock Brake System Warning.....................3-39
Brake System Warning.................................3-38
Change Engine Oil......................................3-45
Charging System.........................................3-36
Check Gages Warning.................................3-47
Check Gas Cap..........................................3-49
Cruise Control.............................................3-46
Gate Ajar...................................................3-48
Highbeam On.............................................3-47
Low Fuel Warning.......................................3-49
Malfunction Indicator....................................3-41
Passenger Airbag Status Indicator..................3-34
Reduced Engine Power................................3-46
Safety Belt Reminders..................................3-32
Security.....................................................3-46
Service Four-Wheel-Drive Warning Light.........3-47
StabiliTrak®Indicator....................................3-40
StabiliTrak®Service......................................3-39
Tire Pressure..............................................3-41
Lighting
Entry.........................................................3-18
Exit...........................................................3-18
7