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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
Brake Master Cylinder — Brake Fluid Level Check
The fluid level of the master cylinder should be checked
when performing under the hood service, or immedi-
ately if the “Brake System Warning Light” indicates
system failure.
The brake master cylinder has a translucent plastic
reservoir. 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
full 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.
Refer to “Fluids, Lubricants, and Genuine Parts” in
“Maintaining 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 performance. The proper type of brake
fluid for your vehicle is also identified on the
original factory installed hydraulic master cylinder
reservoir.
(Continued)
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WARNING!(Continued)
•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 a open container absorbs moisture from the
air resulting in a lower boiling point. This may
cause it to boil unexpectedly during hard or pro-
longed braking, resulting in sudden brake failure.
This could result in a accident.
• 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.
(Continued)
WARNING! (Continued)
•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 an accident.
Clutch Hydraulic System
The clutch hydraulic system is a sealed maintenance-free
system. In the event of leakage or other malfunction, the
system must be replaced.
Transfer Case — If Equipped
Drain And Refill
Refer to the “Maintenance Schedule” for the proper
maintenance intervals.
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Selection of Lubricant
Refer to “Fluids, Lubricants, and Genuine Parts” in
“Maintaining Your Vehicle” for fluid specifications.
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.
Manual Transmission — If Equipped
Selection of Lubricant
Refer to “Fluids, Lubricants, and Genuine Parts” in
“Maintaining Your Vehicle” for fluid specifications.
Fluid Level Check
The fluid level can be checked by removing the filler
plug. If the level of the lubricant is more than 1/2 in (12
mm) below the bottom of the filler hole while the vehicleis on level ground, enough lubricant should be added to
bring the level to 1/4 in (6 mm) below the bottom of the
filler hole.
Automatic Transmission — If Equipped
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, Lubricants, and Genuine Parts” in this
section for fluid 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.
306 MAINTAINING YOUR VEHICLE
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CAUTION!
Using a transmission fluid other than the manufac-
turer ’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, Lubricants, and
Genuine Parts” in this section for fluid specifica-
tions.
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. The only exception to this policy is the use
of special dyes for diagnosing fluid leaks. 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
It is best to check the fluid level when the transmission is
at normal operating temperature (170-180°F / 77-82°C for
68RFE transmission, or 158-176°F / 70-80°C for AS69RC
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
EVIC/DID screen (refer to “Electronic Vehicle Informa-
tion Center [EVIC]” or “Driver Information Display
[DID]” for further information).
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Use the following procedure to check the transmission
fluid level properly:
1. Monitor the transmission temperature using theEVIC/DID screen, 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 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 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 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 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.
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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 68RFE transmis-
sion, or 68-86°F / 20-30°C for AS69RC 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. 8. 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.
Fluid And Filter Changes
Refer to the “Maintenance Schedule” for the proper
maintenance intervals.
In addition, change the fluid and filter(s) if the fluid
becomes contaminated (with water, etc.), or if the trans-
mission is disassembled for any reason.6
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Noise Control System Required Maintenance &
Warranty
All vehicles built over 10,000 lbs. (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.
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Required Maintenance For Noise Control Systems
The following maintenance services must be performed
every six months or 7,500 miles (12 000 km) whichever
comes first, to assure proper operation of the noise
control systems. In addition, inspection and service
should be performed anytime a malfunction is observed
or suspected. Proper maintenance of the entire vehicle
will help the effectiveness of the noise control systems.
Exhaust System
Inspect the entire exhaust system for leaks and damaged
parts. Devices such as hangers, clamps, and U-bolts
should be tight and in good condition. Damaged compo-
nents, burned or blown out mufflers, burned or rusted
out exhaust pipes should be replaced according to the
procedures and specifications outlined in the appropriate
service manual.Air Cleaner Assembly
Inspect air cleaner housing for proper assembly and fit.
Make certain that the air cleaner is properly positioned
and that the cover is tight. Check all hoses leading to the
air cleaner for tightness. The air filter element must also
be clean and serviced according to the instructions out-
lined in the Maintenance Schedule section of this manual.
Tampering With Noise Control System Prohibited
Federal law prohibits the following acts or the causing
thereof: (1) the removal or rendering inoperative by any
person, other than for purposes of maintenance, repair, or
replacement, of any device or element of design incorpo-
rated into any new vehicle for the purpose of noise
control prior to its sale or delivery to the ultimate
purchaser or while it is in use, or (2) the use of the vehicle
after such device or element of design has been removed
or rendered inoperative by any person.
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