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.
P (Park):This position locks the 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) underShifting Into Park on
page 2-43for more information.{CAUTION:
It is dangerous to get out of the vehicle if the shift
lever is not fully in P (Park) with the parking brake
rmly 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). SeeShifting Into
Park on page 2-43. If you are pulling a trailer, see
Towing a Trailer on page 5-40.
R (Reverse):Use this gear to back up.
Notice:Shifting to R (Reverse) while the vehicle is
moving forward could damage the transmission.
The repairs would not be covered by the vehicle
warranty. Shift to R (Reverse) only after the vehicle
is stopped.
2-36
Also see “Tow Haul Mode” underTowing a Trailer on
page 5-40for more information.
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 5-39.
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 2-36for
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 seeTowing a Trailer on page 5-40for 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.
SeeAutomatic Transmission Operation on page 2-36.
2-40
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 nd out how,
seeShifting Into Park on page 2-43.
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.
SeeJump Starting on page 6-40for more information.
To shift out of P (Park) use the following:
1. Apply the brake pedal.
2. Move the shift lever to the desired position.
If you still are unable to shift out of P (Park):
1. Ease the pressure on the shift lever.
2. While holding down the brake pedal, press the shift
lever all the way into P (Park).
3. Move the shift lever to the desired position.
If you are still having a problem shifting, then have the
vehicle serviced soon.
2-44
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 rmly.
{CAUTION:
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 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 speci cations in
Capacities and Speci cations on page 6-110.
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.
6-38