torque GMC YUKON 2008 Owner's Manual

See “Range Selection Mode” later in this section.
PARK (P):This position locks your rear wheels. It is
the best position to use when you start the engine
because your vehicle cannot move easily. When parked
on a hill, especially when the vehicle has a heavy
load, you might notice an increase in the effort to shift
out of Park. See Torque Lock (Automatic Transmission)
underShifting Into PARK (P) on page 2-44for more
information.
{CAUTION:
It is dangerous to get out of your vehicle if the
shift lever is not fully in PARK (P) with the
parking brake rmly set. Your vehicle can roll.
Do not leave your vehicle when the engine is
running unless you have to. If you have left the
engine running, the vehicle can move
suddenly. You or others could be injured. To
be sure your vehicle will not move, even when
you are on fairly level ground, always set your
parking brake and move the shift lever to
PARK (P). SeeShifting Into PARK (P) on
page 2-44. If you are pulling a trailer, see
Towing a Trailer on page 4-49. Allison Transmission
®or Hydra-Matic®6-Speed
Automatic Transmission
2-32

Low Traction Mode
If your vehicle has the Allison Transmission®,orthe
Hydra-Matic®6-Speed Automatic Transmission, it has a
Low Traction Mode that assist in vehicle acceleration
when road conditions are slippery, such as with ice
or snow. While the vehicle is at a stop, select the second
gear range using the Range Selection system. This
will limit torque to the wheels after it detects wheel slip,
preventing the tires from spinning.
Tow/Haul Mode
Your vehicle has a Tow/Haul mode. The selector button
is located on the end of the column shift lever.You can use this feature to assist when towing or
hauling a heavy load or if there is a need to charge a
battery installed in a trailer. SeeTowing a Trailer
on page 4-49for more information.
When Tow/Haul mode is
selected the Tow/Haul
indicator light will come on.
The Tow/Haul mode works with the Autoride
®feature, if
the vehicle has this, to enhance the ride when
trailering or with a loaded vehicle. SeeAutoride
®on
page 4-49.
2-37

Slow ashing means the shift is in progress. It will stay on
when the shift is completed. If for some reason the
transfer case cannot make a requested shift, it will return
to the last chosen setting.
2
m(Two-Wheel Drive High):This setting is used for
driving in most street and highway situations. Your
front axle is not engaged in two-wheel drive. This setting
also provides the best fuel economy.
AUTO (Automatic Four-Wheel Drive):This setting is
ideal for use when road surface traction conditions
are variable. When driving your vehicle in AUTO, the
front axle is engaged, but the vehicle’s power is primarily
sent to the rear wheels. When the vehicle’s software
determines a need for more traction, the system
will transfer more power to the front wheels. Driving in
this mode results in slightly lower fuel economy than
Two-Wheel Drive High.
4
m(Four-Wheel Drive High):Use the four-wheel
high position when you need extra traction, such as on
snowy or icy roads or in most off-road situations.
This setting also engages your front axle to help drive
your vehicle. This is the best setting to use when
plowing snow.
4
n(Four-Wheel Drive Low):This setting also
engages your front axle and delivers extra torque. You
may never need this setting. It sends maximum power to
all four wheels. You might choose Four-Wheel Drive Lowif you are driving off-road in deep sand, deep mud, deep
snow, and while climbing or descending steep hills.
StabiliTrak
®will not engage in this mode. See
StabiliTrak®System on page 4-6for more information.
{CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the
transmission is in PARK (P). You or someone
else could be seriously injured. Be sure to set
the parking brake before placing the transfer
case in NEUTRAL. SeeParking Brake on
page 2-43.
NEUTRAL (N):Shift the vehicle’s transfer case to
NEUTRAL only when towing your vehicle. See
Recreational Vehicle Towing on page 4-45orTowing
Your Vehicle on page 4-45for more information.
If the SERVICE 4 WHEEL DRIVE message stays on,
you should take your vehicle to your dealer for service.
See “SERVICE 4 WHEEL DRIVE message” under
DIC Warnings and Messages on page 3-64.
2-39

Leaving Your Vehicle With the Engine
Running
{CAUTION:
It can be dangerous to leave your vehicle with
the engine running. Your vehicle could move
suddenly if the shift lever is not fully in PARK
(P) with the parking brake rmly set.
If you have four-wheel drive and your transfer
case is in NEUTRAL, your vehicle will be free to
roll, even if your shift lever is in PARK (P). So be
sure the transfer case is in a drive gear — not in
NEUTRAL.
And, if you leave the vehicle with the engine
running, it could overheat and even catch re.
You or others could be injured. Do not leave
your vehicle with the engine running unless you
have to.If you have to leave your vehicle with the engine
running, be sure your vehicle is in PARK (P) and the
parking brake is rmly set before you leave it. After you
move the shift lever into PARK (P), hold the regular
brake pedal down. Then, see if you can move the shift
lever away from PARK (P) without rst pulling it
toward you. If you can, it means that the shift lever was
not fully locked into PARK (P).
Torque Lock
If you are parking on a hill and you do not shift your
transmission into PARK (P) properly, the weight of the
vehicle may put too much force on the parking pawl
in the transmission. You may nd it difficult to pull the
shift lever out of PARK (P). This is called torque lock. To
prevent torque lock, set the parking brake and then
shift into PARK (P) properly before you leave the driver’s
seat. To nd out how, seeShifting Into PARK (P) on
page 2-44.
When you are ready to drive, move the shift lever out of
PARK (P) before you release the parking brake.
If torque lock does occur, you may need to have another
vehicle push yours a little uphill to take some of the
pressure from the parking pawl in the transmission, then
you will be able to pull the shift lever out of PARK (P).
2-45

Brake Wear
Your vehicle has disc brakes. Disc brake pads have
built-in wear indicators that make a high-pitched warning
sound when the brake pads are worn and new pads
are needed. The sound can come and go or be heard all
the time your vehicle is moving, except when you are
pushing on the brake pedal rmly.
{CAUTION:
The brake wear warning sound means that
soon the brakes will not work well. That could
lead to an accident. When you hear the brake
wear warning sound, have your vehicle
serviced.
Notice:Continuing to drive with worn-out brake
pads could result in costly brake repair.
Some driving conditions or climates can cause a brake
squeal when the brakes are rst applied or lightly
applied. This does not mean something is wrong with
the brakes.Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in
the proper sequence to torque specications in
Capacities and Specifications on page 5-124.
Brake linings should always be replaced as complete
axle sets.
Brake Pedal Travel
See your dealer/retailer if the brake pedal does not
return to normal height, or if there is a rapid increase in
pedal travel. This could be a sign that brake service
might be required.
Brake Adjustment
Every time you make a brake stop, the disc brakes
adjust for wear.
5-44

When rotating your vehicle’s tires, always use the
correct rotation pattern shown here.
Do not include the spare tire in the tire rotation.
After the tires have been rotated, adjust the front
and rear ination pressures as shown on the Tire
and Loading Information label. SeeInflation - Tire
Pressure on page 5-72andLoading Your Vehicle
on page 4-35.
Reset the Tire Pressure Monitor System. SeeTire
Pressure Monitor Operation on page 5-75.Make certain that all wheel nuts are properly
tightened. See “Wheel Nut Torque” under
Capacities and Specifications on page 5-124.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after 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 needed, to get all the rust or dirt
off. SeeChanging a Flat Tire on page 5-88.
Make sure the spare tire is stored securely. Push,
pull, and then try to rotate or turn the tire. If it
moves, tighten the cable. SeeStoring a Flat or
Spare Tire and Tools on page 5-104.
5-79

{CAUTION:
Never use oil or grease on studs or nuts.
Because the nuts might come loose. The
vehicle’s wheel could fall off, causing a crash.
8. Put the wheel nuts back on with the rounded end
of the nuts toward the wheel after mounting the
spare tire.
9. Tighten each wheel nut by hand. Then use the
wheel wrench to tighten the nuts until the wheel
is held against the hub.
10. Turn the wheel wrench counterclockwise to lower
the vehicle. Lower the jack completely.
{CAUTION:
Incorrect or improperly tightened wheel nuts
can cause the wheel to come loose and even
come off. This could lead to a crash. 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 5-124for 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 5-124for the wheel nut
torque specication.
5-99

ApplicationCapacities
English Metric
6L90-Transmission 6.3 qt 6.0 L
Transfer Case Fluid 2.0 qt 1.9 L
Wheel Nut Torque 140 lb ft 190Y
†Oil lter should be changed at every oil change.
After rell, the level must be rechecked. Add enough engine coolant so that the uid is within the proper operating
range.
Engine Specications
Engine VIN Code Transmission Spark Plug Gap
4.8L V8 C Automatic 0.040 in (1.01 mm)
5.3L V8 Flexible Fuel with
Active Fuel Management™
(Iron Block)0 Automatic 0.040 in (1.01 mm)
5.3L V8 Flexible Fuel with
Active Fuel Management™
(Aluminum Block)3 Automatic 0.040 in (1.01 mm)
5.3L V8 with Active Fuel
Management™ (Iron Block)J Automatic 0.040 in (1.01 mm)
6.0L V8 (Iron Block) K Automatic 0.040 in (1.01 mm)
6.0L V8 with Active Fuel
Management™
(Aluminum Block)Y Automatic 0.040 in (1.01 mm)
5-125