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.
Light Electric Heavy Electric Light EOH
Heavy EOH
Type of Trailer Brakes Electric Trailer Brakes Electric Trailer Brakes Electric over Hydrau- lic Trailer BrakesElectric over Hydrau-
lic Trailer Brakes
Load *Under 10,000 lbs *Above 10,000 lbs *Under 10,000 lbs *Above 10,000 lbs
* The suggested selection depends and may change de-
pending on the customer preferences for braking perfor-
mance. Condition of the trailer brakes, driving and road
state may also affect the selection.
Display Messages
The trailer brake control interacts with the instrument
cluster display. Display messages, along with a single
chime, will be displayed when a malfunction is determined
in the trailer connection, trailer brake control, or on the
trailer. Refer to “Instrument Cluster Display” in “Getting
To Know Your Instrument Panel” for further information.
CAUTION!
Connecting a trailer that is not compatible with the
ITBM system may result in reduced or complete loss of
trailer braking. There may be a increase in stopping
distance or trailer instability which could result in
damage to your vehicle, trailer, or other property.
WARNING!
Connecting a trailer that is not compatible with the
ITBM system may result in reduced or complete loss of
trailer braking. There may be a increase in stopping
distance or trailer instability which could result in
personal injury.
6
STARTING AND OPERATING 429
Towing Tips
Before setting out on a trip, practice turning, stopping, and
backing up the trailer in an area located away from heavy
traffic.
Automatic Transmission
The DRIVE range can be selected when towing. The
transmission controls include a drive strategy to avoid
frequent shifting when towing. However, if frequent shift-
ing does occur while in DRIVE, select TOW/HAUL mode
or select a lower gear range (using the Electronic Range
Select (ERS) shift control).
NOTE:Using TOW/HAUL mode or selecting a lower
gear range (using the ERS shift control) while operating the
vehicle under heavy loading conditions will improve per-
formance and extend transmission life by reducing exces-
sive shifting and heat build up. This action will also
provide better engine braking.
When towing a loaded trailer up steep grades at low
speeds (20 mph [32 km/h] or below), holding your vehicle
in first gear (using the ERS shift control) can help to avoid
transmission overheating.
If you regularly tow a trailer for more than 45 minutes of
continuous operation, then change the automatic transmis-
sion fluid and filter(s) as specified for police, taxi, fleet, or
Seven-Pin Connector
1 — Battery5 — Ground
2 — Backup Lamps 6 — Left Stop/Turn
3 — Right Stop/Turn 7 — Running Lamps
4 — Electric Brakes
6
STARTING AND OPERATING 431
WARNING!
Do not attempt to change a tire on the side of the
vehicle close to moving traffic, pull far enough off the
road to avoid being hit when operating the jack or
changing the wheel.
2. Place the gear selector into PARK. On four-wheel drive vehicles, shift the transfer case to the 4L position.
3. Turn on the Hazard Warning flasher.
4. Apply the parking brake.
5. Turn the ignition OFF.
6.
Block both the front and rear of the wheel diagonally
opposite the jacking position. For example, if the right front
wheel is being changed, block the left rear wheel.
NOTE: Passengers should not remain in the
vehicle when the vehicle is being jacked.
Jacking Instructions (1500 Series)
WARNING!
Carefully follow these tire changing warnings to help
prevent personal injury or damage to your vehicle:
• Always park on a firm, level surface as far from the
edge of the roadway as possible before raising the
vehicle.
• Turn on the Hazard Warning flasher.
• Block the wheel diagonally opposite the wheel to be
raised.
• Set the parking brake firmly and set the transmission
in PARK.
• Never start or run the engine with the vehicle on a
jack.
• Do not let anyone sit in the vehicle when it is on a
jack.
• Do not get under the vehicle when it is on a jack. If
you need to get under a raised vehicle, take it to a
service center where it can be raised on a lift.
• Only use the jack in the positions indicated and for
lifting this vehicle during a tire change.
(Continued)
7
IN CASE OF EMERGENCY 475
WARNING!
Do not attempt to change a tire on the side of the
vehicle close to moving traffic, pull far enough off the
road to avoid being hit when operating the jack or
changing the wheel.
2. Place the gear selector into PARK. On four-wheel drive vehicles, shift the transfer case to the 4L position.
3. Turn on the Hazard Warning flasher.
4. Apply the parking brake.
5. Turn the ignition OFF.
6.
Block both the front and rear of the wheel diagonally
opposite the jacking position. For example, if the right front
wheel is being changed, block the left rear wheel.
NOTE: Passengers should not remain in the
vehicle when the vehicle is being jacked.
Jacking Instructions (2500 And 3500 Series)
WARNING!
Carefully follow these tire changing warnings to help
prevent personal injury or damage to your vehicle:
• Always park on a firm, level surface as far from the
edge of the roadway as possible before raising the
vehicle.
• Turn on the Hazard Warning flasher.
• Block the wheel diagonally opposite the wheel to be
raised.
• Set the parking brake firmly and set the transmission
in PARK.
• Never start or run the engine with the vehicle on a
jack.
• Do not let anyone sit in the vehicle when it is on a
jack.
• Do not get under the vehicle when it is on a jack. If
you need to get under a raised vehicle, take it to a
service center where it can be raised on a lift.
• Only use the jack in the positions indicated and for
lifting this vehicle during a tire change.
(Continued)
7
IN CASE OF EMERGENCY 491
Severe Duty All Models
NOTE: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 predomi-
nantly at idle, or only very low engine RPM’s. This type of
vehicle use is considered Severe Duty.
Once A Month Or Before A Long Trip:
• Check engine oil level
• Check windshield washer fluid level
• Check tire pressure and look for unusual wear or
damage. Rotate tires at the first sign of irregular wear,
even if it occurs before the oil indicator system turns on.
• Check the fluid levels of the coolant reservoir, brake
master cylinder, power steering (2500/3500 Models
Only) and automatic transmission (six-speed only) and
fill as needed
• Check function of all interior and exterior lightsMaintenance Plan
Required Maintenance
Refer to the Maintenance Plan on the following pages for
required maintenance.
At Every Oil Change Interval As Indicated By Oil
Change Indicator System:
•Change oil and filter.
• Rotate the tires. Rotate at the first sign of irregular
wear, even if it occurs before the oil indicator
system turns on.
• Inspect battery and clean and tighten terminals as
required.
• Inspect automatic transmission fluid if equipped
with dipstick.
• Inspect brake pads, shoes, rotors, drums, hoses and
park brake.
• Inspect engine cooling system protection and hoses.
• Inspect exhaust system.
• Inspect engine air cleaner if using in dusty or
off-road conditions.
• Lube the front drive shaft fitting (2500/3500 (4x4)
models only).
518 SERVICING AND MAINTENANCE
Mileage or time passed (which-ever comes first)
20,000
30,000
40,000
50,000
60,000
70,000
80,000
90,000
100,000
110,000
120,000
130,000
140,000
150,000
Or Years: 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Or Kilometers:
32,000
48,000
64,000
80,000
96,000
112,000
128,000
144,000
160,000
176,000
192,000
208,000
224,000
240,000
Inspect the brake linings, replace
as necessary. XXX X X X X
Adjust parking brake as necessary. X X X X X X X
Inspect transfer case fluid. XX X
Additional Maintenance
Replace cabin air filter. XX X XX XX
Replace engine air filter. XX X X X
Replace spark plugs. ** X
Flush and replace the engine cool-
ant at 10 years or 150,000 miles
(240,000 km) whichever comes
first. XX
Change automatic transmission
fluid and filter(s) (six-speed auto-
matic only), if using your vehicle
for police, taxi, fleet, or frequent
trailer towing. XX
520 SERVICING AND MAINTENANCE
WARNING!(Continued)
in a tightly closed container. Keep the master cylin-
der reservoir cap secured at all times. Brake fluid in
a open container absorbs moisture from the air
resulting in a lower boiling point. This may cause it
to boil unexpectedly during hard or prolonged brak-
ing, resulting in sudden brake failure. This could
result in a collision.
• Overfilling the brake fluid reservoir can result in
spilling brake fluid on hot engine parts, causing the
brake fluid to catch fire. Brake fluid can also damage
painted and vinyl surfaces, care should be taken to
avoid its contact with these surfaces.
• Do not allow petroleum based fluid to contaminate
the brake fluid. Brake seal components could be
damaged, causing partial or complete brake failure.
This could result in a collision.
Automatic Transmission
Selection Of Lubricant
It is important to use the proper transmission fluid to
ensure optimum transmission performance and life. Use
only the manufacturer ’s specified transmission fluid. Refer
to “Fluids And Lubricants” in “Technical Specifications”. It is important to maintain the transmission fluid at the
correct level using the recommended fluid. No chemical
flushes should be used in any transmission; only the
approved lubricant should be used.
CAUTION!
Using a transmission fluid other than the manufactur-
er ’s recommended fluid may cause deterioration in
transmission shift quality and/or torque converter
shudder, and will require more frequent fluid and
filter changes. Refer to “Fluids And Lubricants” in
“Technical Specifications” for fluid specifications.
Special Additives
The manufacturer strongly recommends against using any
special additives in the transmission. Automatic Transmis-
sion Fluid (ATF) is an engineered product and its perfor-
mance may be impaired by supplemental additives. There-
fore, do not add any fluid additives to the transmission.
The only exception to this policy is the use of special dyes
for diagnosing fluid leaks in six-speed transmissions.
Avoid using transmission sealers as they may adversely
affect seals.
8
SERVICING AND MAINTENANCE 553
3. Run the engine at normal idle speed for at least 60seconds, and leave the engine running for the rest of this
procedure.
4. Fully apply the parking brake, and press the brake pedal.
5. Place the gear selector momentarily into each gear position (allowing time for the transmission to fully
engage in each position), ending with the transmission
in PARK.
6. Remove the dipstick, wipe it clean and reinsert it until seated.
7. Remove the dipstick again and note the fluid level on both sides. The fluid level reading is only valid if there
is a solid coating of oil on both sides of the dipstick.
Note that the holes in the dipstick will be full of fluid if
the actual level is at or above the hole. The fluid level
should be between the “HOT” (upper) reference holes
on the dipstick at normal operating temperature. If the
fluid level is low, add fluid through the dipstick tube to
bring it to the proper level. Do not overfill.Use ONLY
the specified fluid (see Fluids And Lubricants for fluid
specifications). After adding any quantity of oil through the dipstick tube, wait a minimum of two minutes for
the oil to fully drain into the transmission before re-
checking the fluid level.
NOTE: If it is necessary to check the transmission below
the operating temperature, the fluid level should be be-
tween the two “COLD” (lower) holes on the dipstick with
the fluid at 60-70°F / 16-21°C. Only use the COLD region
of the dipstick as a rough reference when setting the fluid
level after a transmission service or fluid change. Re-check
the fluid level, and adjust as required, once the transmis-
sion reaches normal operating temperature.
CAUTION!
If the fluid temperature is below 50 °F (10 °C) it may
not register on the dipstick. Do not add fluid until the
temperature is elevated enough to produce an accurate
reading. Run the engine at idle, in PARK, to warm the
fluid.
8. Reinsert the dipstick. Check for leaks. Release the park- ing brake.
8
SERVICING AND MAINTENANCE 555