Page 589 of 669

Cooling System Pressure Cap
The cap must be fully tightened to prevent loss of engine
coolant (antifreeze), and to ensure that the engine coolant
(antifreeze) will return to the radiator from the coolant
expansion bottle.
The cap should be inspected and cleaned if there is any
accumulation of foreign material on the sealing surfaces.
WARNING!
•Do not open hot engine cooling system. Never add
engine coolant (antifreeze) when the engine is
overheated. Do not loosen or remove the cap to cool
an overheated engine. Heat causes pressure to
build up in the cooling system. To prevent scalding
or injury, do not remove the pressure cap while the
system is hot or under pressure.
(Continued)
WARNING! (Continued)
•Do not use a pressure cap other than the one
specified for your vehicle. Personal injury or en-
gine damage may result.
Disposal Of Used Engine Coolant
Used ethylene glycol-based engine coolant (antifreeze) is
a regulated substance requiring proper disposal. Check
with your local authorities to determine the disposal
rules for your community. To prevent ingestion by ani-
mals or children, do not store ethylene glycol-based
engine coolant (antifreeze) in open containers or allow it
to remain in puddles on the ground. If ingested by a child
or pet, seek emergency assistance immediately. Clean up
any ground spills immediately.
7
MAINTAINING YOUR VEHICLE 587
Page 590 of 669

Checking Coolant Level — 6.4L Engine
The level of the coolant in the pressurized coolant bottle
should be between the “MIN” and “MAX” range on the
bottle when the engine is cold.
The radiator normally remains completely full, so there is
no need to remove the cap unless checking for coolant
freeze point or replacing engine coolant (antifreeze).
Advise your service attendant of this. As long as the
engine operating temperature is satisfactory, the coolant
bottle need only be checked once a month. When addi-
tional engine coolant (antifreeze) is needed to maintain
the proper level, it should be added to the coolant bottle.
Do not overfill.
Points To Remember
NOTE:When the vehicle is stopped after a few miles/
kilometers of operation, you may observe vapor coming
from the front of the engine compartment. This is nor-
mally a result of moisture from rain, snow, or high
humidity accumulating on the radiator and being vapor-
ized when the thermostat opens, allowing hot engine
coolant (antifreeze) to enter the radiator.
If an examination of your engine compartment shows no
evidence of radiator or hose leaks, the vehicle may be
safely driven. The vapor will soon dissipate.
• Do not overfill the coolant expansion bottle.
•
Check the coolant freeze point in the radiator and in the
coolant expansion bottle. If engine coolant (antifreeze)
needs to be added, the contents of the coolant expansion
bottle must also be protected against freezing.
588 MAINTAINING YOUR VEHICLE
Page 593 of 669

WARNING!(Continued)
•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 models with 9.25 in Front Axles and 11.5 in Rear
Axles, refer to “Fluids, Lubricants, And Genuine Parts”
in “Maintaining Your Vehicle” for further information.
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.
When checking the fluid level (4500/5500 only), the
vehicle should be in a level position. The fluid level
should be ¼ in±¼in(6.4 mm ± 6.4 mm) below the fill
hole on the front axle. The fluid level should be level with
the bottom of the fill hole on the rear axle.
7
MAINTAINING YOUR VEHICLE 591
Page 596 of 669

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 addi-
tives. Therefore, do not add any fluid additives to the
transmission. Avoid using transmission sealers as they
may adversely affect seals.
CAUTION!
Do not use chemical flushes in your transmission as
the chemicals can damage your transmission compo-
nents. Such damage is not covered by the New
Vehicle Limited Warranty.
Fluid Level Check
Check the fluid level when the engine is fully warmed up
and the transmission fluid is at normal operating tem-
perature. Driving with an improper fluid level will
greatly reduce the life of the transmission and of the
fluid. Check the fluid level whenever the vehicle is
serviced.
Fluid Level Check — Procedure
It is best to check the fluid level when the transmission is
at normal operating temperature (170-180°F / 77-82°C for
66RFE transmission, or 158–176°F / 70–80°C for AS66RC
transmission). 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
594 MAINTAINING YOUR VEHICLE
Page 597 of 669

EVIC/DID display (refer to “Electronic Vehicle Informa-
tion Center (EVIC)/Driver Information Display (DID)” in
“Understanding Your Instrument Panel” for further in-
formation).
Use the following procedure to check the transmission
fluid level properly:
1. Monitor the transmission temperature using theEVIC/DID display, and operate the vehicle as re-
quired to reach the normal operating temperature. If
the transmission is not functioning properly, or the
vehicle cannot be driven, see the NOTE and CAU-
TION 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 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 shift lever momentarily into each gear posi- tion (allowing time for the transmission to fully en-
gage in each position), ending with the transmission in
PARK.
6. Wipe the area around the dipstick clean to prevent dirt from entering the transmission.
7. Remove the dipstick, wipe it clean and reinsert it until seated.
8. 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
7
MAINTAINING YOUR VEHICLE 595
Page 598 of 669

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 quantity of oil through the dipstick tube, wait a
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 for 66RFE transmis-
sion, or 68-86°F / 20-30°C for AS66RC transmission. 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 transmission 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.
9. Reinsert the dipstick. Check for leaks. Release the parking brake.
NOTE: To prevent dirt and water from entering the
transmission after checking or replenishing fluid, make
sure that the dipstick cap is properly reseated. It is
normal for the dipstick cap to spring back slightly from
its fully seated position, as long as its seal remains
engaged in the dipstick tube.
596 MAINTAINING YOUR VEHICLE
Page 629 of 669

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 trans-
mission and fill as needed.
• Check function of all interior and exterior lights
Required Maintenance
Refer to the Maintenance Schedules on the following
pages for required maintenance.
At Every Oil Change Interval As Indicated By Oil Change Indicator System:
•Change oil and filter.
At Every Oil Change Interval As Indicated By Oil
Change Indicator System:
•Rotate the tires. Rotate at the first sign of irregu-
lar 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. 8
MAINTENANCE SCHEDULES 627
Page 650 of 669

Bulb Replacement........................ .615
Bulbs, Light ..........................117,614
Cab Top Clearance Lights ...................619
Camera, Rear ........................... .201
Capacities, Antifreeze (Engine Coolant) ..........621
Capacities, Fluid ......................... .621
Caps, Filler Oil (Engine) .......................... .566
Power Steering ........................ .434
Radiator (Coolant Pressure) ................587
Carbon Monoxide Warning ...............114,498
Cargo Light ............................ .168
Car Washes ............................ .598
Center High Mounted Stop Light ..............618
Center Seat Storage Compartment .............218
Certification Label ........................ .500
Chart, Tire Sizing ........................ .457
Check Engine Light (Malfunction Indicator Light) . .561 Checking Your Vehicle For Safety
..............114
Checks, Safety ............................114
Child Restraint ............................82
Child Restraints Booster Seats ...........................87
Child Restraints .........................82
Child Seat Installation .................99, 102
How To Stow An Unused ALR Seat Belt ........98
Infants And Child Restraints ................84
Install A LATCH-Compatible Child Restraint ....97
Installing Child Restraints Using The Vehicle Seat
Belt ..................................99
Locating The LATCH Anchorages ............94
Lower Anchors And Tethers For Children .......89
Older Children And Child Restraints ..........86
Seating Positions ........................88
Cigar Lighter ............................211
Clean Air Gasoline ....................... .494
648 INDEX