ELECTRONIC BRAKE CONTROL SYSTEM
Your vehicle is equipped with an advanced Electronic
Brake Control system (EBC). This system includes Elec-
tronic Brake Force Distribution (EBD), Anti-Lock Brake
System (ABS), Brake Assist System (BAS), Hill Start Assist
(HSA), Traction Control System (TCS), Electronic Stability
Control (ESC), and Electronic Roll Mitigation (ERM). These
systems work together to enhance both vehicle stability
and control in various driving conditions.
Your vehicle may also be equipped with Trailer Sway
Control (TSC) and Hill Descent Control (HDC).
Electronic Brake Force Distribution (EBD)
This function manages the distribution of the braking
torque between the front and rear axles by limiting braking
pressure to the rear axle. This is done to prevent overslip of
the rear wheels to avoid vehicle instability, and to prevent
the rear axle from entering ABS before the front axle.
Brake System Warning Light
The red “Brake System Warning Light” will turn on when
the ignition switch is turned to the ON position and may
stay on for as long as four seconds. If the “Brake System Warning Light” remains on or comes
on while driving, it indicates that the brake system is not
functioning properly and that immediate service is re-
quired. If the “Brake System Warning Light” does not come
on when the ignition switch is turned to the ON position,
have the light repaired as soon as possible.
Anti-Lock Brake System (ABS)
The Anti-Lock Brake System (ABS) provides increased
vehicle stability and brake performance under most brak-
ing conditions. The system automatically prevents wheel
lock, and enhances vehicle control during braking.
The ABS performs a self-check cycle to ensure that the ABS
is working properly each time the vehicle is started and
driven. During this self-check, you may hear a slight
clicking sound as well as some related motor noises.
ABS is activated during braking when the system detects one
or more wheels begins to lock. Road conditions such as ice,
snow, gravel, bumps, railroad tracks, loose debris, or panic
stops may increase the likelihood of ABS activation(s).
You also may experience the following when ABS activates:
• The ABS motor noise (it may continue to run for a short
time after the stop). 5STARTING AND OPERATING 353
Traction Control System (TCS)
This system monitors the amount of wheel spin of each of
the driven wheels. If wheel spin is detected, the TCS may
apply brake pressure to the spinning wheel(s) and/or
reduce engine power to provide enhanced acceleration and
stability. A feature of the TCS, Brake Limited Differential
(BLD), functions similar to a limited slip differential and
controls the wheel spin across a driven axle. If one wheel
on a driven axle is spinning faster than the other, the
system will apply the brake of the spinning wheel. This
will allow more engine torque to be applied to the wheel
that is not spinning. BLD may remain enabled even if TCS
and ESC are in a reduced mode.
Electronic Stability Control (ESC)
This system enhances directional control and stability of
the vehicle under various driving conditions. ESC corrects
for oversteering or understeering of the vehicle by apply-
ing the brake of the appropriate wheel(s) to assist in
counteracting the oversteer or understeer condition. En-
gine power may also be reduced to help the vehicle
maintain the desired path.
ESC uses sensors in the vehicle to determine the vehicle
path intended by the driver and compares it to the actual
path of the vehicle. When the actual path does not match the intended path, ESC applies the brake of the appropriate
wheel to assist in counteracting the oversteer or understeer
condition.
• Oversteer - when the vehicle is turning more than
appropriate for the steering wheel position.
• Understeer - when the vehicle is turning less than
appropriate for the steering wheel position.
The “ESC Activation/Malfunction Indicator Light” located
in the instrument cluster will start to flash as soon as the ESC
system becomes active. The “ESC Activation/Malfunction
Indicator Light” also flashes when the TCS is active. If the
“ESC Activation/Malfunction Indicator Light” begins to
flash during acceleration, ease up on the accelerator and
apply as little throttle as possible. Be sure to adapt your
speed and driving to the prevailing road conditions.
WARNING!• Electronic Stability Control (ESC) cannot prevent the
natural laws of physics from acting on the vehicle,
nor can it increase the traction afforded by prevailing
road conditions. ESC cannot prevent accidents, in-
cluding those resulting from excessive speed in (Continued)358 STARTING AND OPERATING
WARNING! (Continued)• The Electronic Stability Control (ESC) cannot pre-
vent the natural laws of physics from acting on the
vehicle, nor can it increase the traction afforded by
prevailing road conditions. ESC cannot prevent all
accidents, including those resulting from excessive
speed in turns, driving on very slippery surfaces, or
hydroplaning. ESC also cannot prevent collisions.
ESC Activation/Malfunction Indicator Light and ESC
OFF Indicator Light
The “ESC Activation/Malfunction Indicator
Light” in the instrument cluster will come on
when the ignition switch is turned to the ON
position. It should go out with the engine run-
ning. If the “ESC Activation/Malfunction Indicator Light”
comes on continuously with the engine running, a mal-
function has been detected in the ESC system. If this light
remains on after several ignition cycles, and the vehicle has
been driven several miles (kilometers) at speeds greater
than 30 mph (48 km/h), see your authorized dealer as soon
as possible to have the problem diagnosed and corrected. The “ESC Activation/Malfunction Indicator Light” (lo-
cated in the instrument cluster) starts to flash as soon as the
tires lose traction and the ESC system becomes active. The
“ESC Activation/Malfunction Indicator Light” also flashes
when TCS is active. If the “ESC Activation/Malfunction
Indicator Light” begins to flash during acceleration, ease
up on the accelerator and apply as little throttle as possible.
Be sure to adapt your speed and driving to the prevailing
road conditions.
NOTE:
• The “ESC Activation/Malfunction Indicator Light” and
the “ESC OFF Indicator Light” come on momentarily
each time the ignition switch is turned ON.
• Each time the ignition is turned ON, the ESC system will
be ON even if it was turned off previously.
• The ESC system will make buzzing or clicking sounds
when it is active. This is normal; the sounds will stop
when ESC becomes inactive following the maneuver
that caused the ESC activation.
The “ESC OFF Indicator Light” indicates the
customer has elected to have the Electronic Sta-
bility Control (ESC) in a reduced mode. 5STARTING AND OPERATING 361
Feedback To The Driver
The instrument cluster has an HDC icon and the HDC
switch has an LED which offer feedback to the driver about
the state HDC is in.
• The cluster icon and switch lamp will illuminate and
remain on solid when HDC is enabled or activated. This
is the normal operating condition for HDC.
• The cluster icon and switch lamp will flash for several
seconds then extinguish when the driver pushes the
HDC switch but enable conditions are not met.
• The cluster icon and switch lamp will flash for several
seconds then extinguish when HDC disables due to
excess speed.
• The cluster icon and switch lamp will flash when HDC
deactivates due to overheated brakes. The flashing will
stop and HDC will activate again once the brakes have
cooled sufficiently.
WARNING!HDC is only intended to assist the driver in controlling
vehicle speed when descending hills. The driver must
remain attentive to the driving conditions and is re-
sponsible for maintaining a safe vehicle speed. TIRE SAFETY INFORMATION
Tire Markings
1 — U.S. DOT Safety Standards
Code (TIN) 4 — Maximum Load
2 — Size Designation 5 — Maximum Pressure
3 — Service Description 6 — Treadwear, Traction and
Temperature Grades 5STARTING AND OPERATING 365
Damaged Run Flat tires, or Run Flat tires that have
experienced a loss of pressure should be replaced immedi-
ately with another Run Flat tire of identical size and service
description (Load Index and Speed Symbol).
Tire Types
All Season Tires — If Equipped
All season tires provide traction for all seasons (Spring,
Summer, Fall and Winter). Traction levels may vary be-
tween different all season tires. All season tires can be
identified by the M+S, M&S, M/S or MS designation on the
tire sidewall. Use all season tires only in sets of four; failure
to do so may adversely affect the safety and handling of
your vehicle.
Summer Or Three Season Tires — If Equipped
Summer tires provide traction in both wet and dry condi-
tions, and are not intended to be driven in snow or on ice.
If your vehicle is equipped with Summer tires, be aware
these tires are not designed for Winter or cold driving
conditions. Install Winter tires on your vehicle when am-
bient temperatures are less than 40°F (5°C) or if roads are
covered with ice or snow. For more information, contact an
authorized dealer. Summer tires do not contain the all season designation or
mountain/snowflake symbol on the tire sidewall. Use
Summer tires only in sets of four; failure to do so may
adversely affect the safety and handling of your vehicle.
WARNING!Do not use Summer tires in snow/ice conditions. You
could lose vehicle control, resulting in severe injury or
death. Driving too fast for conditions also creates the
possibility of loss of vehicle control.
Snow Tires
Some areas of the country require the use of snow tires
during the Winter. Snow tires can be identified by a
“mountain/snowflake” symbol on the tire sidewall.
If you need snow tires, select tires
equivalent in size and type to the origi-
nal equipment tires. Use snow tires only
in sets of four; failure to do so may
adversely affect the safety and handling
of your vehicle.
Snow tires generally have lower speed ratings than what
was originally equipped with your vehicle and should not
be operated at sustained speeds over 75 mph (120 km/h). 5STARTING AND OPERATING 379
WARNING!• Do not use a tire, wheel size or rating other than that
specified for your vehicle. Some combinations of
unapproved tires and wheels may change suspen-
sion dimensions and performance characteristics,
resulting in changes to steering, handling, and brak-
ing of your vehicle. This can cause unpredictable
handling and stress to steering and suspension com-
ponents. You could lose control and have a collision
resulting in serious injury or death. Use only the tire
and wheel sizes with load ratings approved for your
vehicle.
• Never use a tire with a smaller load index or capacity,
other than what was originally equipped on your
vehicle. Using a tire with a smaller load index could
result in tire overloading and failure. You could lose
control and have a collision.
• Failure to equip your vehicle with tires having ad-
equate speed capability can result in sudden tire
failure and loss of vehicle control. CAUTION!Replacing original tires with tires of a different size
may result in false speedometer and odometer read-
ings.
TIRE CHAINS (TRACTION DEVICES)
Use of traction devices require sufficient tire-to-body clear-
ance. Follow these recommendations to guard against
damage.
• Traction device must be of proper size for the tire, as
recommended by the traction device manufacturer. 5STARTING AND OPERATING 385
Please follow the table below for proper tire size, chain
type, and axle recommendations:
Vehicle Axle
Recommenda-
tions Tire Sizes Chain Class
Chassis Cab 3500 (Single Rear Wheel) Models Rear Only LT265/70R18E U Class
Chassis Cab 3500 (Dual Rear Wheel) 4X2 Models Rear Only LT235/80R17E U Class
Chassis Cab 3500 (Dual Rear Wheel) 4X4 Models Front/Rear LT235/80R17E U Class
Chassis Cab 4500/5500 Models Rear Only 225/70R19.5G U Class
WARNING!Using tires of different size and type (M+S, Snow)
between front and rear axles can cause unpredictable
handling. You could lose control and have a collision.
CAUTION!To avoid damage to your vehicle or tires, observe the
following precautions:
• Because of restricted traction device clearance be-
tween tires and other suspension components, it is (Continued) CAUTION! (Continued)important that only traction devices in good condi-
tion are used. Broken devices can cause serious
damage. Stop the vehicle immediately if noise occurs
that could indicate device breakage. Remove the
damaged parts of the device before further use.
• Install device as tightly as possible and then re-
tighten after driving about ½ mile (0.8 km).
• Do not exceed 30 mph (48 km/h).
• Drive cautiously and avoid severe turns and large
bumps, especially with a loaded vehicle. (Continued)386 STARTING AND OPERATING
CAUTION! (Continued)• When replacing a flat, the spare tire may have to be
remounted on the rim or installed at a different
location to maintain the correct placement of the tire
on the wheel relative to the tire/wheel position on
the vehicle. For example, if the spare is used to
replace an outer rear tire it will have to be remounted
on the rim so that the wheel is dished inward. That
way the tread design of asymmetrical tires will
maintain proper position.
DEPARTMENT OF TRANSPORTATION UNIFORM
TIRE QUALITY GRADES
The following tire grading categories were established by
the National Highway Traffic Safety Administration. The
specific grade rating assigned by the tire’s manufacturer in
each category is shown on the sidewall of the tires on your
vehicle.
All passenger vehicle tires must conform to Federal safety
requirements in addition to these grades. Treadwear
The Treadwear grade is a comparative rating, based on the
wear rate of the tire when tested under controlled condi-
tions on a specified government test course. For example, a
tire graded 150 would wear one and one-half times as well
on the government course as a tire graded 100. The relative
performance of tires depends upon the actual conditions of
their use, however, and may depart significantly from the
norm due to variations in driving habits, service practices,
and differences in road characteristics and climate.
Traction Grades
The Traction grades, from highest to lowest, are AA, A, B,
and C. These grades represent the tire’s ability to stop on
wet pavement, as measured under controlled conditions on
specified government test surfaces of asphalt and concrete.
A tire marked C may have poor traction performance.
WARNING!The traction grade assigned to this tire is based on
straight-ahead braking traction tests, and does not
include acceleration, cornering, hydroplaning, or peak
traction characteristics. 5STARTING AND OPERATING 389