Automatic Transmission Operation
The vehicle has a Hydra-Matic®6L80 automatic
transmission, and has an electronic shift position
indicator within the instrument panel cluster.
The electronic shift position indicator displays when
the shift lever is moved out of P (Park).
There are several different positions for the shift lever.
Light Duty 6‐Speed Automatic Transmission Shown (Heavy Duty 6‐Speed Similar)
See “Range Selection Mode” later in this section.
P (Park) : This position locks your rear wheels. It is the
best position to use when you start the engine because
the vehicle cannot move easily. When parked on a hill, especially when the vehicle has
a heavy load, you may notice an increase in the effort
to shift out of P (Park). See Torque Lock (Automatic
Transmission) under
Shifting Into Park
on page 3‑37for more information.
{WARNING:
It is dangerous to get out of the vehicle if the shift
lever is not fully in P (Park) with the parking brake
firmly set. The vehicle can roll.
Do not leave the 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 the
vehicle will not move, even when you are on fairly
level ground, always set the parking brake and
move the shift lever to P (Park). See Shifting Into
Park
on page 3‑37. If you are pulling a trailer,
see Towing a Trailer on page 5‑42.
3-30
Grade Braking
The Grade Braking shift modes can be activated by
pressing the button on the end of the shift control lever.
While in Range Selection Mode , Grade Braking is
deactivated allowing the driver to select a desired range
of gears.
Grade Braking is only active while the Tow/Haul Mode
is selected and you are not in the Range Selection
Mode. See“Tow/Haul Mode listed previously and
Automatic Transmission Operation
on page 3‑30for
more information on the Range Selection Mode. Grade
Braking assists in maintaining desired vehicle speeds
when driving on downhill grades by automatically
implementing a shift schedule that utilizes the engine
and transmission to slow the vehicle. This reduces wear
on the braking system and increases control of the
vehicle. Grade Braking monitors vehicle speed,
acceleration, engine torque and brake pedal usage.
Using this information, it detects when the vehicle is on
a downhill grade and the driver desires to slow the
vehicle by pressing the brake.
Also see Towing a Trailer
on page 5‑42for more
information.
Cruise Grade Braking
Cruise Grade Braking assists when driving on a
downhill grade. It maintains vehicle speed by
automatically implementing a shift schedule that uses
the engine and the transmission to slow the vehicle.
Cruise Grade Braking operates while Cruise Control is
engaged in Tow/Haul mode to assist in maintaining
vehicle speed under loaded vehicle conditions.
It utilizes vehicle acceleration and deviation from
desired speed to determine the correct gear for the
operating condition. If vehicle speed is above the
desired speed the transmission will downshift to slow
the vehicle. If vehicle speed is near or below desired
speed the trans will upshift, allowing vehicle speed to
increase.
While in the Range Select Mode (RSM) mode, cruise
grade braking is not available.
See Automatic Transmission Operation on page 3‑30.
3-35
Torque Lock
If you are parking on a hill and you do not shift the
transmission into P (Park) properly, the weight of the
vehicle can put too much force on the parking pawl in
the transmission. It might be difficult to pull the shift
lever out of P (Park). This is called torque lock.
To prevent torque lock, set the parking brake and then
shift into P (Park) properly before you leave the driver
seat. To find out how, seeShifting Into Park
on
page 3‑37.
When you are ready to drive, move the shift lever out
of P (Park) before releasing the parking brake.
If torque lock does occur, you might 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 should be able to pull the shift lever out of
P (Park).
Shifting Out of Park
This vehicle is equipped with an electronic shift lock
release system. The shift lock release is designed to:
.Prevent ignition key removal unless the shift lever
is in P (Park) with the shift lever button fully
released, and
.Prevent movement of the shift lever out of
P (Park), unless the ignition is in ON/RUN or
ACC/ACCESSORY and the regular brake pedal
is applied.
The shift lock release is always functional except in the
case of an uncharged or low voltage (less than 9 volt)
battery.
If the vehicle has an uncharged battery or a battery with
low voltage, try charging or jump starting the battery.
See Jump Starting
on page 6‑42for more information.
3-38
Brake Wear
This 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 the vehicle is moving, except when
applying the brake pedal firmly.
{WARNING:
The brake wear warning sound means that soon
the brakes will not work well. That could lead to
an accident. When the brake wear warning sound
is heard, have the 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 first 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 specifications in
Capacities and Specifications on page 6‑115.
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 brake stop, the disc brakes adjust for wear.
Replacing Brake System Parts
The braking system on a vehicle is complex. Its many
parts have to be of top quality and work well together if
the vehicle is to have really good braking. The vehicle
was designed and tested with top-quality brake parts.
When parts of the braking system are replaced
—for
example, when the brake linings wear down and new
ones are installed —be sure to get new approved
replacement parts. If this is not done, the brakes might
6-40
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 inflation pressures as shown on the Tire
and Loading Information label. SeeInflation - Tire
Pressure
on page 6‑64and Loading the Vehicleon
page 5‑31
.
Reset the Tire Pressure Monitor System. See Tire
Pressure Monitor Operation
on page 6‑68. Make certain that all wheel nuts are properly
tightened. See
“Wheel Nut Torque” under
Capacities and Specifications
on page 6‑115.
{WARNING:
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.
See Changing a Flat Tire
on page 6‑80.
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. See Storing a Flat or
Spare Tire and Tools
on page 6‑94.
6-72
8. Put the wheel nuts back on with the rounded endof 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.
{WARNING:
Wheel nuts that are improperly or incorrectly
tightened can cause the wheels to become loose
or come off. The wheel nuts should be tightened
with a torque wrench to the proper torque
specification after replacing. Follow the torque
specification supplied by the aftermarket
manufacturer when using accessory locking
wheel nuts. See Capacities and Specifications
on
page 6‑115
for original equipment wheel nut
torque specifications. 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 specification. See Capacities and
Specifications
on page 6‑115for the wheel nut
torque specification.
11. Tighten the nuts firmly in a crisscross
sequence as shown by
turning the wheel
wrench clockwise.
When you reinstall the regular wheel and tire, you must
also reinstall the center cap, if your vehicle has one.
Line up the tabs on the back of the center cap with
the slot on the wheel. The cap only goes in one way.
Place the cap on the wheel and gently press until it
snaps into place.
6-90
Capacities and Specifications
The following approximate capacities are given in English and metric conversions. SeeRecommended Fluids and
Lubricantson page 7‑11for more information.
Application Capacities
English Metric
Air Conditioning Refrigerant For the air conditioning system refrigerant charge amount,
see the refrigerant caution label located under the hood. See your dealer/retailer for more information.
Cooling System 18.1 qt17.1 L
Engine Oil with Filter 6.0 qt†5.7 L†
Fuel Tank Regular 26.0 gal98.4 L
Extended 31.5 gal119.2 L
Transmission Fluid (Pan Removal and Filter Replacement) 6.0 qt5.7 L
Transfer Case Fluid 1.5 qt1.4 L
Wheel Nut Torque 140 lb ft190Y
All capacities are approximate. When adding, be sure to fill to the approximate level, as recommended in this manual.
Recheck fluid level after filling.
†Oil filter should be changed at every oil change.
Engine Specifications
Engine VIN CodeTransmission Spark Plug Gap
6.2L V8 FAutomatic 0.040 in (1.02 mm)
6-115