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 3‑35for 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 3‑35. If you are pulling a trailer,
see Towing a Trailer on page 5‑42.
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.
To rock the vehicle back and forth to get out of snow,
ice, or sand without damaging the transmission, see If
Your Vehicle is Stuck in Sand, Mud, Ice, or Snow
on
page 5‑29.
3-28
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 3‑28for
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 truck 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 3‑28.
3-33
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 3‑35.
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 6‑44for 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.
3-36
To remove or install cargo tie-downs at the front of the
bed, slide the corner cap towards the center of the bed
to expose the rail notches. To remove the corner cap,
pull either edge away from the rail.
To remove the system, loosen the toggle bolts on each
rail until they can be removed from the bed of the truck.
To replace the system, place the toggle bolts and rails
into their original locations and tighten them to a torque
setting of 12.5 ft lbs (17Y).
If the system is removed to install a bed liner, make
sure there is no bed liner material in the installation
points.
Notice: If cargo is tied down using the horizontal
slots on the top of the pickup box, the box could be
damaged. Using the horizontal slots on the top of
the pickup box for tie-down locations may cause
damage to the pickup box and would not be
covered by the vehicle warranty. Only use the
tie-down loops if the vehicle does not have the
cargo management system.Sunroof
On vehicles with a power sliding sunroof, the ignition
needs to be turned to RUN, or the Retained Accessory
Power (RAP) must be activated to open or close the
sunroof. When RAP is active, the sunroof will work for
10 minutes after the ignition is turned off, or until the
driver's door is opened. See Retained Accessory Power
(RAP)
on page 3‑24for more information.
There are two sunroof
switches located in the
overhead console above
the rearview mirror.
Vent : From the closed position, press the rear of the
passenger's side switch to vent the sunroof. To close
the sunroof, press and hold the front of the passenger's
side switch.
3-61
Brake Wear
This vehicle has front disc brakes and could have rear
drum brakes or rear 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 6‑122.
If the vehicle has rear drum brakes, they do not have
wear indicators, but if a rear brake rubbing noise is
heard, have the rear brake linings inspected
immediately. Rear brake drums should be removed and
inspected each time the tires are removed for rotation or
changing. Drum brakes have an inspection hole to
inspect lining wear during scheduled maintenance.
When the front brake pads are replaced, have the rear
brakes inspected, too.
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 brakes adjust for wear.
6-42
Reset the Tire Pressure Monitor System. SeeTire
Pressure Monitor Operation
on page 6‑74.
Make certain that all wheel nuts are properly
tightened. See “Wheel Nut Torque” under
Capacities and Specifications
on page 6‑122.
{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 6‑86.
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 6‑100.
When It Is Time for New Tires
Various factors, such as maintenance, temperatures,
driving speeds, vehicle loading, and road conditions,
influence when you need new tires.
One way to tell when it is
time for new tires is to
check the treadwear
indicators, which appear
when your tires have only
1/16 inch (1.6 mm) or less
of tread remaining. Some
commercial truck tires
may not have treadwear
indicators.
6-79
{WARNING:
Never use oil or grease on bolts or nuts because
the nuts might come loose. The vehicle's wheel
could fall off, causing a crash.
7. Put the wheel nutsback on with the
rounded end of the
nuts toward the wheel
after mounting the
spare. Tighten each
wheel nut by hand.
Then use the wheel
wrench to tighten the
nuts until the wheel is
held against the hub.
8. 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 6‑122
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 6‑122for the wheel nut torque
specification.
6-96
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 16.8 qt15.9 L
Engine Oil with Filter 6.0 qt†5.7 L†
Fuel Tank 26.0 gal98.4 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 lbft190Y
All capacities are approximate. When adding, be sure to fill to the approximate level, as recommended in this manual.
Recheck fluid after filling.
†Oil filter should be changed at every oil change.
Engine Specifications
Engine VIN CodeTransmission Spark Plug Gap
6.2L V8 2Automatic 0.040 in (1.01 mm)
6-122