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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 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.
(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 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 re-
quired. 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
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hole on the front axle. The fluid level should be level with
the bottom of the fill hole on the rear axle.
Drain And Refill
On 4500/5500 vehicles, remove the lower bolt to drain
the axle fluid.Refer to the “Maintenance Schedule” for the proper
maintenance intervals.
1 — 4500/5500 Rear Axle Fluid Fill Plug
2 — 4500/5500 Rear Axle Fluid Drain Plug
472 MAINTAINING YOUR VEHICLE
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Lubricant Selection
Refer to “Fluids, Lubricants, and Genuine Parts” in
“Maintaining Your Vehicle” for further information.
NOTE:The presence of water in the gear lubricant will
result in corrosion and possible failure of differential
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 NOT REQUIRE any
limited slip oil additive (friction modifiers).
NOTE: Slight noise and mild shuddering may be evi-
dent while turning a vehicle with limited slip differential
on concrete or dry pavement. These conditions should be
considered normal operation of the limited slip differen-
tial.
Transfer Case
Drain And Refill
Refer to the “Maintenance Schedule” for the proper
maintenance intervals.
Lubricant Selection
Refer to “Fluids, Lubricants, and Genuine Parts” in
“Maintaining Your Vehicle” for further information.
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.
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Automatic Transmission — Aisin F21-250 HD
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.
CAUTION!
Using a transmission fluid other than the manufac-
turer ’s recommended fluid may cause deterioration
(Continued)
CAUTION!(Continued)
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.
474 MAINTAINING YOUR VEHICLE
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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 AS66RCtransmission). 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 display (see Electronic Vehicle Information Center
[EVIC] for further information).
Use the following procedure to check the transmission
fluid level properly:
1. Monitor the transmission temperature using the EVIC
display, and operate the vehicle as required to reach
the normal operating temperature.
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.
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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
fluid level is low, add fluid through the dipstick tube
to bring it to the proper level. Do not overfill.UseONLY the recommended fluid (see
Fluids, Lubri-
cants, 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.
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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. 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 — Six-Speed
Transmission
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.
Appearance Care And Protection From Corrosion
Protection Of Body And Paint From Corrosion
Vehicle body care requirements vary according to geo-
graphic locations and usage. Chemicals that make roads
passable in snow and ice, and chemicals that are sprayed
on trees and road surfaces during other seasons, are
highly corrosive to the metal in your vehicle. Outside
parking, which exposes your vehicle to airborne contami-
nants, road surfaces on which the vehicle is operated,
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extreme hot or cold weather and other extreme condi-
tions will have an adverse effect on paint, metal trim, and
underbody protection.
The following maintenance recommendations will enable
you to obtain maximum benefit from the corrosion
resistance built into your vehicle.
What Causes Corrosion?
Corrosion is the result of deterioration or removal of
paint and protective coatings from your vehicle.
The most common causes are:
•Road salt, dirt and moisture accumulation.
• Stone and gravel impact.
• Insects, tree sap and tar.
• Salt in the air near seacoast localities.
• Atmospheric fallout/industrial pollutants.
Washing
•Wash your vehicle regularly. Always wash your ve-
hicle in the shade using MOPAR® Car Wash, or a mild
car wash soap, and rinse the panels completely with
clear water.
• If insects, tar, or other similar deposits have accumu-
lated on your vehicle, use MOPAR® Super Kleen Bug
and Tar Remover to remove.
• Use a high quality cleaner wax, such as MOPAR®
Cleaner Wax to remove road film, stains and to protect
your paint finish. Take care never to scratch the paint.
• Avoid using abrasive compounds and power buffing
that may diminish the gloss or thin out the paint finish.
478 MAINTAINING YOUR VEHICLE