weight limitations are met. Store the heavier items down
low and be sure that the weight is distributed equally. Stow
all loose items securely before driving.
Improper weight distributions can have an adverse effect
on the way your vehicle steers and handles and the way
the brakes operate.
CAUTION!
Do not load your vehicle any heavier than the GVWR
or the maximum front and rear GAWR. If you do, parts
on your vehicle can break, or it can change the way
your vehicle handles. This could cause you to lose
control. Also overloading can shorten the life of your
vehicle.
TRAILER TOWING
In this section you will find safety tips and information on
limits to the type of towing you can reasonably do with
your vehicle. Before towing a trailer, carefully review this
information to tow your load as efficiently and safely as
possible.To maintain the New Vehicle Limited Warranty coverage,
follow the requirements and recommendations in this
manual concerning vehicles used for trailer towing.
Common Towing Definitions
The following trailer towing related definitions will assist
you in understanding the following information:
Gross Vehicle Weight Rating (GVWR)
The GVWR is the total allowable weight of your vehicle.
This includes driver, passengers, cargo and tongue weight.
The total load must be limited so that you do not exceed
the GVWR. Refer to “Vehicle Loading/Vehicle Certification
Label” in “Starting And Operating” for further informa-
tion.
Gross Trailer Weight (GTW)
The GTW is the weight of the trailer plus the weight of all
cargo, consumables and equipment (permanent or tempo-
rary) loaded in or on the trailer in its
loaded and ready for
operation condition.
The recommended way to measure GTW is to put your
fully loaded trailer on a vehicle scale. The entire weight of
the trailer must be supported by the scale.
290 STARTING AND OPERATING
Consider the following items when computing the weight
on the rear axle of the vehicle:
•The tongue weight of the trailer.
• The weight of any other type of cargo or equipment put
in or on your vehicle.
• The weight of the driver and all passengers.
NOTE: Remember that everything put into or on the
trailer adds to the load on your vehicle. Also, additional
factory-installed options or dealer-installed options must
be considered as part of the total load on your vehicle.
Refer to the “Tire And Loading Information” placard for
the maximum combined weight of occupants and cargo for
your vehicle.
Towing Requirements
To promote proper break-in of your new vehicle drivetrain
components, the following guidelines are recommended.
CAUTION!
• Do not tow a trailer at all during the first 500 miles
(805 km) the new vehicle is driven. The engine, axle
or other parts could be damaged.
(Continued)
CAUTION! (Continued)
•Then, during the first 500 miles (805 km) that a trailer
is towed, do not drive over 50 mph (80 km/h) and do
not make starts at full throttle. This helps the engine
and other parts of the vehicle wear in at the heavier
loads.
Perform the maintenance listed in the “Scheduled Servic-
ing”. Refer to “Scheduled Servicing” in “Servicing And
Maintenance” for the proper maintenance intervals. When
towing a trailer, never exceed the GAWR or GCWR ratings.
WARNING!
Improper towing can lead to a collision. Follow these
guidelines to make your trailer towing as safe as
possible:
• Make certain that the load is secured in the trailer
and will not shift during travel. When trailering
cargo that is not fully secured, dynamic load shifts
can occur that may be difficult for the driver to
control. You could lose control of your vehicle and
have a collision.
(Continued)
298 STARTING AND OPERATING
GAIN
The GAIN setting is used to set the trailer brake control for
the specific towing condition and should be changed as
towing conditions change. Changes to towing conditions
include trailer load, vehicle load, road conditions and
weather.
Adjusting GAIN
NOTE:This should only be performed in a traffic free
environment at speeds of approximately 20–25 mph
(30–40 km/h).
1. Make sure the trailer brakes are in good working condition, functioning normally and properly adjusted.
See your trailer dealer if necessary.
2. Hook up the trailer and make the electrical connections according to the trailer manufacturer’s instructions.
3. When a trailer with electric/EOH brakes is plugged in, the trailer connected message should appear in the
instrument cluster display (if the connection is not
recognized by the ITBM, braking functions will not be
available), the GAIN setting will illuminate and the
correct type of trailer must be selected from the instru-
ment cluster display options. 4. Push the UP or DOWN button on the steering wheel
until “TRAILER TOW” appears on the screen.
5. Push the RIGHT arrow on the steering wheel to enter “TRAILER TOW”.
6. Push the UP or DOWN buttons until the Trailer Brake Type appears on the screen.
7. Push the RIGHT arrow and then push the UP or DOWN buttons until the proper Trailer Brake Type appears on
the screen.
8. In a traffic-free environment, tow the trailer on a dry, level surface at a speed of 20–25 mph (30–40 km/h) and
squeeze the manual brake control lever completely.
9. If the trailer wheels lockup (indicated by squealing tires), reduce the GAIN setting; if the trailer wheels turn
freely, increase the GAIN setting.
Repeat steps 8 and 9 until the GAIN setting is at a point just
below trailer wheel lockup. If towing a heavier trailer,
trailer wheel lockup may not be attainable even with the
maximum GAIN setting of 10.
302 STARTING AND OPERATING
Dual wheel models require a special heavy-duty lug nut
tightening adapter (included with the vehicle) to correctly
tighten the lug nuts. Also, when it is necessary to remove
and install dual rear wheels, use a proper vehicle lifting
device.
NOTE:When installing a spare tire (if equipped) as part of
a dual rear wheel end combination, the tire diameter of the
two individual tires must be compared. If there is a
significant difference, the larger tire should be installed in
a front location. The correct direction of rotation for dual
tire installations must also be observed.
It is recommended that wheel stud nuts be kept torqued to
specifications at all times. Torque wheel stud nuts to
specifications at each lubrication interval.
Wheel Nuts
All wheel nuts should be tightened occasionally to elimi-
nate the possibility of wheel studs being sheared or the bolt
holes in the wheels becoming elongated. This is especially
important during the first few hundred miles/kilometers
of operation to allow the wheel nuts to become properly
set. All wheel nuts should first be firmly seated against the
wheel. The wheel nuts should then be tightened to recom-
mended torque. Tighten the wheel nuts to final torque in increments. Progress around the bolt circle, tightening the
wheel nut opposite to the wheel nut just previously
tightened until final torque is achieved.
To Stow The Flat Or Spare — If Equipped
Refer to Upfitters Body Builders Guide for information on
stowing your spare tire (if equipped).
Hub Caps/Wheel Covers — If Equipped
The hub caps must be removed before raising the vehicle
off the ground.
CAUTION!
Use extreme caution when removing the front and rear
center caps. Damage can occur to the center cap and/or
the wheel if screwdriver type tools are used. A pulling
motion, not a pry off motion, is recommended to
remove the caps.
For single rear wheel (SRW) models, use the flat blade on
the end of the lug wrench to pull the hub cap off. Insert the
blade end into the pull off notch and carefully pull the hub
cap off with a back and forth motion.
On 3500 models with dual rear wheels (DRW), you must
first remove the hub caps. The jack handle driver has a
342 IN CASE OF EMERGENCY
TIRES ............................... .392
▫ Tire Safety Information ..................392
▫ Tires — General Information ..............401
▫ Tire Types ........................... .407
▫ Spare Tires — If Equipped ................409
▫ Wheel And Wheel Trim Care ..............411
▫ Tire Chains (Traction Devices) .............412
▫ Tire Rotation Recommendations ............414
DEPARTMENT OF TRANSPORTATION UNIFORM
TIRE QUALITY GRADES ..................416
▫ Treadwear ........................... .416
▫ Traction Grades ....................... .416▫
Temperature Grades .....................416
STORING THE VEHICLE ..................417
BODYWORK .......................... .417
▫ Protection From Atmospheric Agents ........417
▫ Body And Underbody Maintenance ..........418
▫ Preserving The Bodywork .................418
INTERIORS ........................... .419
▫ Seats And Fabric Parts ...................419
▫ Plastic And Coated Parts ..................420
▫ Leather Parts ......................... .421
▫ Glass Surfaces ........................ .421
356 SERVICING AND MAINTENANCE
SCHEDULED SERVICING
Your vehicle is equipped with an automatic oil change
indicator system. The oil change indicator system will
remind you that it is time to take your vehicle in for
scheduled maintenance.
Based on engine operation conditions, the oil change
indicator message will illuminate. This means that service
is required for your vehicle. Operating conditions such as
frequent short-trips, trailer tow, extremely hot or cold
ambient temperatures, and E85 fuel usage will influence
when the “Oil Change Required” message is displayed.
Severe Operating Conditions can cause the change oil
message to illuminate as early as 3,500 miles (5,600 km)
since last reset. Have your vehicle serviced as soon as
possible, within the next 500 miles (805 km).
Your authorized dealer will reset the oil change indicator
message after completing the scheduled oil change. If a
scheduled oil change is performed by someone other than
your authorized dealer, the message can be reset by
referring to the steps described under “Instrument Cluster
Display” in “Getting To Know Your Instrument Panel” for
further information.Gasoline Engines:
Under no circumstances should oil change intervals exceed
8,000 miles (13,000 km), twelve months or 350 hours of
engine run time, whichever comes first. The 350 hours of
engine run or idle time is generally only a concern for fleet
customers.
Severe Duty:
Change Engine Oil at 4,000 miles (6,500 km) or 350 hours of
engine run time if the vehicle is operated in a dusty and off
road environment or is operated predominately at idle or
very low engine RPM’s. This type of vehicle use is consid-
ered Severe Duty.
Once A Month Or Before A Long Trip:
•
Check engine oil level
• Check windshield washer fluid level
• Check the tire inflation pressures and look for unusual
wear or damage
• Check the fluid levels of the coolant reservoir, brake
master cylinder, power steering and automatic transmis-
sion, and fill as needed
• Check function of all interior and exterior lights
8
SERVICING AND MAINTENANCE 357
Tire Inflation Pressures
The proper cold tire inflation pressure is listed on the
driver’s side B-Pillar or rear edge of the driver’s side door.
At least once a month:
•
Check and adjust tire pressure with a good quality pocket-
type pressure gauge. Do not make a visual judgement
when determining proper inflation. Tires may look prop-
erly inflated even when they are under-inflated.
• Inspect tires for signs of tire wear or visible damage.
CAUTION!
After inspecting or adjusting the tire pressure, always
reinstall the valve stem cap. This will prevent moisture
and dirt from entering the valve stem, which could
damage the valve stem.
Inflation pressures specified on the placard are always
“cold tire inflation pressure”. Cold tire inflation pressure is
defined as the tire pressure after the vehicle has not been
driven for at least three hours, or driven less than 1 mile
(1.6 km) after sitting for a minimum of three hours. The
cold tire inflation pressure must not exceed the maximum
inflation pressure molded into the tire sidewall. Check tire pressures more often if subject to a wide range
of outdoor temperatures, as tire pressures vary with tem-
perature changes.
Tire pressures change by approximately 1 psi (7 kPa) per
12°F (7°C) of air temperature change. Keep this in mind
when checking tire pressure inside a garage, especially in
the Winter.
Example: If garage temperature = 68°F (20°C) and the
outside temperature = 32°F (0°C) then the cold tire inflation
pressure should be increased by 3 psi (21 kPa), which
equals 1 psi (7 kPa) for every 12°F (7°C) for this outside
temperature condition.
Tire pressure may increase from 2 to 6 psi (13 to 40 kPa)
during operation. DO NOT reduce this normal pressure
build up or your tire pressure will be too low.
Tire Pressures For High Speed Operation
The manufacturer advocates driving at safe speeds and
within posted speed limits. Where speed limits or condi-
tions are such that the vehicle can be driven at high speeds,
maintaining correct tire inflation pressure is very impor-
tant. Increased tire pressure and reduced vehicle loading
may be required for high-speed vehicle operation. Refer to
your authorized tire dealer or original equipment vehicle
8
SERVICING AND MAINTENANCE 403
dealer for recommended safe operating speeds, loading
and cold tire inflation pressures.
WARNING!
High speed driving with your vehicle under maximum
load is dangerous. The added strain on your tires could
cause them to fail. You could have a serious collision.
Do not drive a vehicle loaded to the maximum capacity
at continuous speeds above 75 mph (120 km/h).
Radial Ply Tires
WARNING!
Combining radial ply tires with other types of tires on
your vehicle will cause your vehicle to handle poorly.
The instability could cause a collision. Always use
radial ply tires in sets of four. Never combine them
with other types of tires.
Tire Repair
If your tire becomes damaged, it may be repaired if it meets
the following criteria:
• The tire has not been driven on when flat. •
The damage is only on the tread section of your tire
(sidewall damage is not repairable).
• The puncture is no greater thana¼ofaninch (6 mm).
Consult an authorized tire dealer for tire repairs and
additional information.
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).
Run Flat Tires — If Equipped
Run Flat tires allow you the capability to drive 50 miles
(80 km) at 50 mph (80 km/h) after a rapid loss of inflation
pressure. This rapid loss of inflation is referred to as the
Run Flat mode. A Run Flat mode occurs when the tire
inflation pressure is of/or below 14 psi (96 kPa). Once a
Run Flat tire reaches the run flat mode it has limited
driving capabilities and needs to be replaced immediately.
A Run Flat tire is not repairable.
It is not recommended driving a vehicle loaded at full
capacity or to tow a trailer while a tire is in the run flat
mode.
See the tire pressure monitoring section for more information.
404 SERVICING AND MAINTENANCE