
348SERVICING AND MAINTENANCE
Inspect the front and rear axle
surfaces. If gear oil leakage is
suspected, check the fluid level. If
using your vehicle for police, taxi,
fleet, off-road or frequent trailer
towing change the axle fluid. X
XXXXX
Inspect the transfer case fluid
(4x4), change for any of the
following: police, taxi, fleet, or
frequent trailer towing. X
XXX X
Change the transfer case fluid
(4x4). X
X
Change automatic transmission
fluid (AS69RC transmission only). X
XXX
Change automatic transmission
fluid and sump filter (AS69RC
transmission only). X
X
Change automatic transmission
fluid and filter(s). X
Mileage Or Time Passed
(Whichever Comes First):
7,500
15,000
22,500
30,000
37,500
45,000
52,500
60,000
67,500
75,000
82,500
90,000
97,500
105,000
112,500
120,000
127,500
135,000
142,500
150,000
Or Months: 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96 102 108 114 120
Or Kilometers:
12,000
24,000
36,000
48,000
60,000
72,000
84,000
96,000
108,000
120,000
132,000
144,000
156,000
168,000
180,000
192,000
204,000
216,000
228,000
240,000
23_DPF_OM_EN_USC_t.book Page 348

352SERVICING AND MAINTENANCE
(Continued)
CHECKING OIL LEVEL
To ensure proper engine lubrication, the engine oil
must be maintained at the correct level. Check the
oil level at regular intervals, such as every fuel
stop. The best time to check the engine oil level is
about five minutes after a fully warmed up engine
is shut off.
Checking the oil while the vehicle is on level ground
will improve the accuracy of the oil level readings.
There are four possible dipstick types:
Crosshatched zone.
Crosshatched zone marked SAFE.
Crosshatched zone marked with MIN at the low
end of the range and MAX at the high end of the
range.
Crosshatched zone marked with dimples at the
MIN and the MAX ends of the range.
NOTE:Always maintain the oil level within the crosshatch
markings on the dipstick.
Adding 1 qt (1 L) of oil when the reading is at the
low end of the dipstick range will raise the oil level
to the high end of the range marking.
ADDING WASHER FLUID
The fluid reservoir is located under the hood and
the fluid level should be checked at regular
intervals. Fill the reservoir with windshield washer
solvent only (not radiator antifreeze). When
refilling the washer fluid reservoir, take some
washer fluid and apply it to a cloth or towel and
wipe the wiper blades clean. This will help blade
performance.
To prevent freeze-up of your windshield washer
system in cold weather, select a solution or mixture
that meets or exceeds the temperature range of
your climate. This rating information can be found
on most washer fluid containers.After the engine has warmed up, operate the
defroster for a few minutes to reduce the
possibility of smearing or freezing the fluid on the
cold windshield. Windshield washer solution used
with water as directed on the container, aids
cleaning action, reduces the freezing point to avoid
line clogging, and is not harmful to paint or trim.MAINTENANCE-FREE BATTERY
Your vehicle is equipped with a maintenance-free
battery. You will never have to add water, and
periodic maintenance is not required.
NOTE:Replacement batteries should both be of equal
capacity to prevent damage to the vehicle's
charging system.
CAUTION!
Overfilling or underfilling the crankcase will
cause oil aeration or loss of oil pressure. This
could damage your engine.
WARNING!
Commercially available windshield washer
solvents are flammable. They could ignite and
burn you. Care must be exercised when filling or
working around the washer solution.
WARNING!
Battery fluid is a corrosive acid solution and
can burn or even blind you. Do not allow
battery fluid to contact your eyes, skin, or
clothing. Do not lean over a battery when
attaching clamps. If acid splashes in eyes or
on skin, flush the area immediately with large
amounts of water Ú
page 334.
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SERVICING AND MAINTENANCE371
(Continued)
To guarantee optimum performance of the system,
keep the surfaces of the charge air cooler,
condenser and radiator clean and free of debris.
Periodically check the hoses leading to and from
the charge air cooler for cracks or loose clamps
resulting in loss of pressure and reduced engine
performance.
BRAKE SYSTEM
In order to ensure brake system performance, all
brake system components should be inspected
periodically Ú
page 344.
Fluid Level Check — Brake Master Cylinder
The fluid level of the master cylinder should be
checked when performing under the hood service
or immediately if the Brake System Warning Light
indicates system failure.
If necessary, add fluid to bring level within the
designated marks on the side of the reservoir of
the brake master cylinder. Be sure to clean the top
of the master cylinder area before removing cap.
With disc brakes the fluid level can be expected to
fall as the brake linings wear. However, an
unexpected drop in fluid level may be caused by a
leak and a system check should be conducted.
For further information Ú page 421.
WARNING!
Riding the brakes can lead to brake failure and
possibly a collision. Driving with your foot resting
or riding on the brake pedal can result in
abnormally high brake temperatures, excessive
lining wear, and possible brake damage. You
would not have your full braking capacity in an
emergency.
WARNING!
Use only manufacturer's recommended brake
fluid Úpage 421. Using the wrong type of
brake fluid can severely damage your brake
system and/or impair its performance. The
proper type of brake fluid for your vehicle is
also identified on the original factory installed
hydraulic master cylinder reservoir.
To avoid contamination from foreign matter or
moisture, use only new brake fluid or fluid that
has been in a tightly closed container. Keep
the master cylinder reservoir cap secured at
all times. Brake fluid in an open container
absorbs moisture from the air resulting in a
lower boiling point. This may cause it to boil
unexpectedly during hard or prolonged
braking, 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 contam -
inate the brake fluid. Brake seal components
could be damaged, causing partial or
complete brake failure. This could result in a
collision.
WARNING!
8
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372SERVICING AND MAINTENANCE
AUTOMATIC TRANSMISSION
Special Additives
The manufacturer strongly recommends against
using any special additives in the transmission.
Automatic Transmission Fluid (ATF) is an
engineered product and its performance may be
impaired by supplemental additives. Therefore, 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 6-speed
transmissions. Avoid using transmission sealers as
they may adversely affect seals.
Fluid Level Check — 8-Speed Transmission
The fluid level is preset at the factory and does not
require adjustment under normal operating
conditions. Routine fluid level checks are not
required, therefore the transmission has no
dipstick. An authorized dealer can check your
transmission fluid level using special service tools. If you notice fluid leakage or transmission
malfunction, visit an authorized dealer
immediately to have the transmission fluid level
checked. Operating the vehicle with an improper
fluid level can cause severe transmission damage.
Fluid Level Check — 6-Speed Transmission
It is best to check the fluid level when the
transmission is at normal operating temperature
(158-176°F / 70-80°C). This normally occurs
after at least 15 miles (25 km) of driving. At normal
operating temperature the fluid cannot be held
comfortably between the fingertips. You can read
the transmission sump temperature in the
instrument cluster screen Ú page 89.
Use the following procedure to check the
transmission fluid level properly:
1. Monitor the transmission temperature using the instrument cluster display, and operate
the vehicle as required to reach the normal
operating temperature. If the transmission is
not functioning properly, or the vehicle cannot be driven, see the following Note and Caution
about checking the fluid level at colder
temperatures.
2. Park the vehicle on level ground.
3. Run the engine at normal idle speed for at least 60 seconds, 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 Ú page 421. After adding any
quantity of oil through the dipstick tube, wait a
CAUTION!
Do not use chemical flushes in your
transmission as the chemicals can damage your
transmission components. Such damage is not
covered by the New Vehicle Limited Warranty.
CAUTION!
If a transmission fluid leak occurs, visit an
authorized dealer immediately. Severe
transmission damage may occur. An authorized
dealer has the proper tools to adjust the fluid
level accurately.
23_DPF_OM_EN_USC_t.book Page 372

SERVICING AND MAINTENANCE373
minimum of two minutes for the oil to fully
drain into the transmission before rechecking
the fluid level.
NOTE:If it is necessary to check the transmission below
the operating temperature, the fluid level should
be between 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 trans -
mission service or fluid change. Re-check the fluid
level, and adjust as required, once the trans -
mission reaches normal operating temperature.
8. Reinsert the dipstick. Check for leaks. Release the parking brake.
NOTE:If it is necessary to check the transmission below
the operating temperature, the fluid level should
be between the two COLD (lower) holes on the
dipstick with the fluid at 68-86°F / 20-30°C. Only
use the COLD region of the dipstick as a rough
reference when setting the fluid level after a trans -
mission service or fluid change. Re-check the fluid
level, and adjust as required, once the trans -
mission reaches normal operating temperature.
Fluid And Filter Changes — 8-Speed
Transmission
Under normal operating conditions, the fluid
installed at the factory will provide satisfactory
lubrication for the life of the vehicle.
Routine fluid and filter changes are not required.
However, change the fluid and filter if the fluid
becomes contaminated (with water, etc.), or if the
transmission is disassembled for any reason.
Fluid And Filter Changes — 6-Speed
Transmission
For the proper maintenance intervals Úpage 344.
In addition, change the fluid and filters if the fluid
becomes contaminated (with water, etc.), or if the
transmission is disassembled for any reason.
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 Ú page 421. 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!
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.
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.
CAUTION!
Using a transmission fluid other than the
manufacturer’s recommended fluid may cause
deterioration in transmission shift quality and/or
torque converter shudder, and (for 6-speed
transmissions) will require more frequent fluid
and filter changes Ú page 421.
8
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374SERVICING AND MAINTENANCE
REAR AXLE AND 4X4 FRONT DRIVING
A
XLE FLUID LEVEL
For normal service, periodic fluid level checks are
not required. When the vehicle is serviced for other
reasons the exterior surfaces of the axle assembly
should be inspected. If gear oil leakage is
suspected, inspect the fluid level with the vehicle
in a level position.
When checking the fluid level, the vehicle should
be in a level position. The fluid level at room
temperature should be as follows:
3500 Front Axle: ¼ inch ± ¼ inch (6.4 mm ±
6.4 mm) below the bottom of the fill hole.
3500 Rear Axle: ¼ inch ± ¼ inch (6.4 mm ±
6.4 mm) below the bottom of the fill hole.
4500/5500 Front Axle: ¼ inch +/- ¼ inch
(6.4 mm ± 6.4 mm) below the bottom of the fill
hole.
4500/5500 Rear Axle: 1/8 inch +/- 1/8 inch (3.2 mm +/- 3.2 mm) below the bottom of the fill
hole.
Drain And Refill
On 4500/5500 vehicles, remove the lower bolt to
drain the axle fluid.
4500/5500 Rear Axle Plugs
For the proper maintenance intervals Úpage 344.
Lubricant Selection
For further information Ú page 421.
NOTE:The presence of water in the gear lubricant will
result in corrosion and possible failure of differ -
ential components. Operation of the vehicle in
water, as may be encountered in some off-highway
types of service, will require draining and refilling
the axle to avoid damage.
Limited-Slip Differentials DO REQUIRE limited slip
oil additive (friction modifiers).
NOTE:Slight noise and mild shuddering may be evident
while turning a vehicle with limited slip differential
on concrete or dry pavement. These conditions
should be considered normal operation of the
limited slip differential.
TRANSFER CASE
Fluid Level Check
This fluid level can be checked by removing the
filler plug. The fluid level should be to the bottom
edge of the filler plug hole with the vehicle in a level
position.
Drain And Refill
For the proper maintenance intervals Úpage 344.
Selection Of Lubricant
Use only the manufacturer's recommended fluid
Úpage 421.
NOISE CONTROL SYSTEM REQUIRED
M
AINTENANCE & WARRANTY
All vehicles built over 10,000 lb (4,535 kg) Gross
Vehicle Weight Rating and manufactured for sale
and use in the United States are required to
comply with the Federal Government's Exterior
Noise Regulations. These vehicles can be
identified by the Noise Emission Control Label
located in the operator's compartment.
1 — 4500/5500 Rear Axle Fluid Fill Plug
2 — 4500/5500 Rear Axle Fluid Drain Plug
23_DPF_OM_EN_USC_t.book Page 374

400SERVICING AND MAINTENANCE
NOTE:Wheel valve stem must be replaced as well when
installing new tires due to wear and tear in existing
tires.
Keep dismounted tires in a cool, dry place with as
little exposure to light as possible. Protect tires
from contact with oil, grease, and gasoline.
Replacement Tires
The tires on your new vehicle provide a balance of
many characteristics. They should be inspected
regularly for wear and correct cold tire inflation
pressures. The manufacturer strongly
recommends that you use tires equivalent to the
originals in size, quality and performance when
replacement is needed Úpage 399. Refer to the
Tire And Loading Information Placard or the
Vehicle Certification Label for the size designation
of your tire. The Load Index and Speed Symbol for
your tire will be found on the original equipment
tire sidewall.
For more information relating to the Load Index
and Speed Symbol of a tire Ú page 389.
It is recommended to replace the two front tires or
two rear tires as a pair. Replacing just one tire can
seriously affect your vehicle’s handling. If you ever
replace a wheel, make sure that the wheel’s
specifications match those of the original wheels. It is recommended you contact an authorized tire
dealer or original equipment dealer with any
questions you may have on tire specifications or
capability. Failure to use equivalent replacement
tires may adversely affect the safety, handling, and
ride of your vehicle.
TIRE TYPES
All Season Tires — If Equipped
All Season tires provide traction for all seasons
(Spring, Summer, Autumn, and Winter). Traction
levels may vary between 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
conditions, 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 ambient
temperatures are less than 40°F (5°C) or if roads
are covered with ice or snow. For more
information, contact an authorized dealer.
WARNING!
Do not use a tire, wheel size, load rating, or
speed rating other than that specified for your
vehicle. Some combinations of unapproved
tires and wheels may change suspension
dimensions and performance characteristics,
resulting in changes to steering, handling, and
braking of your vehicle. This can cause unpre
-
dictable handling and stress to steering and
suspension components. 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 over -
loading and failure. You could lose control and
have a collision.
Failure to equip your vehicle with tires having
adequate 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 readings.
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430 Cooling System
.............................................. 368Adding Coolant (Antifreeze)....................... 369Coolant Level.................................. 368, 370Cooling Capacity........................................ 418Disposal Of Used Coolant.......................... 370Drain, Flush, And Refill.............................. 368Inspection................................................. 370Points To Remember................................. 370Pressure Cap............................................. 369Radiator Cap............................................. 369Selection Of Coolant (Antifreeze)..... 368, 419Corrosion Protection...................................... 407Cruise Control (Speed Control)... 148, 149, 150Cruise Light................................................... 110Customer Assistance..................................... 422Cybersecurity................................................. 199
D
Daytime Running Lights................................... 52Dealer Service............................................... 353Defroster, Rear Window................................... 62Defroster, Windshield............................. 62, 322Delay (Intermittent) Wipers.............................. 57Deleting A Phone........................................... 238Diagnostic System, Onboard......................... 111Diesel Exhaust Brake.................................... 129Diesel Fuel..................................................... 415Diesel Fuel Requirements............................. 415Diesel Fuel System, Re-Priming..................... 363Differential, Limited Slip................................ 147
Dipsticks Power Steering......................................... 148Disabled Vehicle Towing............................... 339Disc Drive..................................................... 232Disconnecting............................................... 238DisposalAntifreeze (Engine Coolant)...................... 370Disturb.......................................................... 241Door Ajar....................................................... 105Door Ajar Light.............................................. 105Door LocksAutomatic.................................................... 27Doors............................................................... 24Draining Fuel/Water Separator Filter............ 360Driver Memory Presets................................. 230Driver’s Seat Back Tilt...................................... 31DrivingThrough Flowing, Rising, Or Shallow Standing Water
................................................... 198Dual Rear Wheels....................... 332, 406, 411
E
Electric Brake Control System....................... 271Anti-Lock Brake System............................ 270Electronic Roll Mitigation................. 272, 277Electrical Power Outlets................................... 71Electronic Range Select (ERS)............. 134, 137Electronic Stability Control (ESC).................. 272Electronic Throttle Control Warning Light...... 104Electronically Shifted Transfer Case.... 140, 143
Emergency Braking.............................. 128, 280Emergency, In Case OfFreeing Vehicle When Stuck..................... 338Hazard Warning Flasher........................... 325Jacking...................................................... 329Jump Starting........................................... 333Emission Control System Maintenance......... 112Engine.................................................. 350, 351Air Cleaner................................................ 355Block Heater............................................. 119Break-In Recommendations............ 127, 128Compartment........................................... 351Compartment Identification...................... 350Coolant (Antifreeze).................................. 419Exhaust Gas Caution................................ 324Fails To Start............................................. 116Flooded, Starting...................................... 116Fuel Requirements................................... 413Identification............................................. 351Idling......................................................... 124Jump Starting........................................... 333Oil.................................................... 353, 419Oil Filler Cap............................................. 350Oil Filter.................................................... 354Oil Reset......................................................92Oil Selection.............................................. 353Oil Synthetic.............................................. 354Overheating.............................................. 335Runaway................................................... 176Starting..................................................... 115
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