Page 576 of 734

CAUTION!
•DO NOT dolly tow any 4WD vehicle. Towing with
only one set of wheels on the ground (front or rear)
will cause severe transmission and/or transfer case
damage. Tow with all four wheels either ON the
ground, or OFF the ground (using a vehicle trailer).
• Tow only in the forward direction. Towing this
vehicle backwards can cause severe damage to the
transfer case.
• Before recreational towing, the transfer case must be
in NEUTRAL. To be certain the transfer case is fully
in NEUTRAL, perform the procedure outlined under
“Shifting Into NEUTRAL”. Internal transmission
damage will result, if the transfer case is not in
NEUTRAL during towing.
• Automatic transmissions must be placed in PARK,
and manual transmissions must be placed in gear
(not in Neutral) for recreational towing.
• Towing this vehicle in violation of the above require-
ments can cause severe transmission and/or transfer
case damage. Damage from improper towing is not
covered under the New Vehicle Limited Warranty.
(Continued)
CAUTION! (Continued)
•Do not disconnect the rear driveshaft because fluid
will leak from the transfer case, causing damage to
internal parts.
• Do not use a bumper-mounted clamp-on tow bar on
your vehicle. The bumper face bar will be damaged.
Shifting Into NEUTRAL (N)
Use the following procedure to prepare your vehicle for
recreational towing.
WARNING!
You or others could be injured or killed if you leave the
vehicle unattended with the transfer case in the NEU-
TRAL (N) position without first fully engaging the
parking brake. The transfer case NEUTRAL (N) posi-
tion disengages both the front and rear drive shaft
from the powertrain, and will allow the vehicle to roll,
even if the automatic transmission is in PARK (or
manual transmission is in gear). The parking brake
should always be applied when the driver is not in the
vehicle.
574 STARTING AND OPERATING
Page 633 of 734

MAINTAINING YOUR VEHICLE
CONTENTS
ENGINE COMPARTMENT — 3.6L ...........633
ENGINE COMPARTMENT — 5.7L ...........634
ENGINE COMPARTMENT — 6.4L ...........635
ONBOARD DIAGNOSTIC SYSTEM (OBD II) . . . .636
▫ Onboard Diagnostic System (OBD II)
Cybersecurity ........................ .636
▫ Loose Fuel Filler Cap Message .............637
EMISSIONS INSPECTION AND
MAINTENANCE PROGRAMS ..............637
REPLACEMENT PARTS ...................639
DEALER SERVICE ...................... .639
MAINTENANCE PROCEDURES .............639
▫ Engine Oil .......................... .640
▫ Engine Oil Filter ...................... .642
▫ Engine Air Cleaner Filter .................643 ▫
Accessory Drive Belt Inspection ............646
▫ Maintenance-Free Battery .................648
▫ Air Conditioner Maintenance ..............649
▫ Front Driveshaft Lubrication — 2500/3500
(Four-Wheel Drive Models Only) ............655
▫ Body Lubrication ..................... .656
▫ Windshield Wiper Blades .................656
▫ Adding Washer Fluid ...................659
▫ Exhaust System ....................... .660
▫ Cooling System ....................... .662
▫ Brake System ........................ .667
▫ Rear Axle And 4x4 Front Driving
Axle Fluid Level ...................... .668
▫ Transfer Case ........................ .669
▫ Automatic
Transmission ..................669
7
Page 635 of 734
ENGINE COMPARTMENT — 3.6L
1 — Air Cleaner Filter
2 — Engine Oil Dipstick
3 — Engine Oil Fill
4 — Brake Fluid Reservoir
5 — Battery6 — Washer Fluid Reservoir
7 — Power Distribution Center (Fuses)
8 — Coolant Pressure Cap
9 — Engine Coolant Reservoir
7
MAINTAINING YOUR VEHICLE 633
Page 636 of 734
ENGINE COMPARTMENT — 5.7L
1 — Air Cleaner Filter7 — Washer Fluid Reservoir
2 — Automatic Transmission Dipstick (6-Speed Trans Only) 8 — Power Distribution Center (Fuses)
3 — Engine Oil Fill 9 — Power Steering Fluid Reservoir (2500/3500 Models Only)
4 — Engine Oil Dipstick 10 — Coolant Pressure Cap
5 — Brake Fluid Reservoir 11 — Engine Coolant Reservoir
6 — Battery 634 MAINTAINING YOUR VEHICLE
Page 637 of 734
ENGINE COMPARTMENT — 6.4L
1 — Coolant Pressure Bottle6 — Battery
2 — Transmission Dipstick 7 — Power Distribution Center (Fuses)
3 — Engine Oil Fill 8 — Washer Solvent
4 — Engine Oil Dipstick 9 — Power Steering Fluid Reservoir
5 — Brake Fluid Reservoir 10 — Air Cleaner Filter
7
MAINTAINING YOUR VEHICLE 635
Page 669 of 734

•Do not change the thermostat for Summer or Winter
operation. If replacement is ever necessary, install ONLY
the correct type thermostat. Other designs may result in
unsatisfactory engine coolant (antifreeze) performance,
poor gas mileage, and increased emissions.
Brake System
In order to assure brake system performance, all brake
system components should be inspected periodically. Refer
to the “Maintenance Schedule” for the proper maintenance
intervals.
WARNING!
Riding the brakes can lead to brake failure and possi-
bly 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.
Brake Fluid Level Check
The fluid level of the master cylinder should be checked
when performing under the hood service or immediately if
the brake system warning lamp indicates system failure. The brake master cylinder has a translucent plastic reser-
voir. On the outboard side of the reservoir, there is a
“MAX” mark and a “MIN” mark. The fluid level must be
kept within these two marks. Do not add fluid above the
MAX mark because leakage may occur at the 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.
Use only the manufacturer’s recommended brake fluid.
Refer to “Fluids, Lubricants, And Genuine Parts” in “Main-
taining Your Vehicle” for further information.
WARNING!
•
Use only manufacturer’s recommended brake fluid.
Refer to “Fluids, Lubricants, And Genuine Parts” in
“Maintaining Your Vehicle” for further information.
Using the wrong type of brake fluid can severely
damage your brake system and/or impair its perfor-
mance. The proper type of brake fluid for your
vehicle is also identified on the original factory
installed hydraulic master cylinder reservoir.
(Continued)
7
MAINTAINING YOUR VEHICLE 667
Page 670 of 734

WARNING!(Continued)
•To avoid contamination from foreign matter or mois-
ture, use only new brake fluid or fluid that has been
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.
Rear Axle And 4x4 Front Driving Axle 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. Refer
to “Fluids, Lubricants, And Genuine Parts” in “Maintain-
ing Your Vehicle” for further information. This inspection
should be made with the vehicle in a level position.
For 1500 Model axles, the fluid level should be even with
the bottom of the fill hole (within 1/4 in (6.4 mm) of edge
of hole) for the FDU215 HD front axle and C235FE rear
axle.
For all 2500/3500 Model axles, the fluid level should be
1/4 in ± 1/4 in (6.4 mm ± 6.4 mm) below the fill hole on the
9.25 in front and 3/4 in ± 1/4 in (19 mm ± 6.4 mm) on
10.5 in rear axles. The 11.5 in rear axle level should be
1/4 in ± 1/4 in (6.4 mm ± 6.4 mm) below the fill hole.
Drain And Refill
Refer to the “Maintenance Schedule” for the proper main-
tenance intervals.
668 MAINTAINING YOUR VEHICLE
Page 673 of 734

Fluid Level Check — Six-Speed Transmission
It is best to check the fluid level when the transmission is
at normal operating temperature (170-180°F / 77-82°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 (refer to “Instrument Cluster Display” for
further information).
Use the following procedure to check the transmission
fluid level properly:
1. Monitor the transmission temperature using the instru-ment cluster display, and operate the vehicle as required
to reach the normal operating temperature. If the trans-
mission is not functioning properly, or the vehicle
cannot be driven, see the NOTE and CAUTION below
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 sec- onds, 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, Lubricants, And Genuine
Parts for fluid specifications). After adding any quan-
tity of oil through the dipstick tube, wait a minimum of
two minutes for the oil to fully drain into the transmis-
sion before rechecking the fluid level.
7
MAINTAINING YOUR VEHICLE 671