•Maintain engine coolant (antifreeze) concentration at a
minimum of 50% OAT coolant (conforming to
MS.90032) and distilled water for proper corrosion pro-
tection of your engine which contains aluminum com-
ponents.
• Make sure that the coolant expansion bottle overflow
hoses are not kinked or obstructed.
• Keep the front of the radiator clean. If your vehicle is
equipped with air conditioning, keep the front of the
condenser clean.
• 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 Plan” in this section 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.
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 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.
386 SERVICING AND MAINTENANCE
Refer to “Fluids And Lubricants” in “Technical Specifica-
tions” for further information.
WARNING!
•Use only manufacturer’s recommended brake fluid.
Refer to “Fluids And Lubricants” in “Technical
Specifications” 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.
• 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.
(Continued)
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.
Automatic Transmission
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 And Lubricants” in “Technical 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.
8
SERVICING AND MAINTENANCE 387
2. Park the vehicle on level ground.
3. Run the engine at normal idle speed for at least 60seconds, 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. 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.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.
NOTE: If it is necessary to check the transmission below
the operating temperature, the fluid level should be be-
tween the two “COLD” (lower) holes on the dipstick with
the fluid at 60-70°F / 16-21°C for 66RFE transmission, 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 tempera-
ture.
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
SERVICING AND MAINTENANCE 389
9. Reinsert the dipstick. Check for leaks. Release the park-ing brake.
NOTE: To prevent dirt and water from entering the trans-
mission 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 Plan” for the proper mainte-
nance intervals.
In addition, change the fluid and filters if the fluid becomes
contaminated (with water, etc.), or if the transmission is
disassembled for any reason.
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 And Lubricants” in “Servicing And Main-
tenance” for further information. For normal service, peri-
odic 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
± ¼ in (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.
Drain And Refill
On 4500/5500 vehicles, remove the lower bolt to drain the
axle fluid.
4500/5500 Rear Axle Plugs
1 — 4500/5500 Rear Axle Fluid Fill Plug
2 — 4500/5500 Rear Axle Fluid Drain Plug
390 SERVICING AND MAINTENANCE
TECHNICAL SPECIFICATIONS
CONTENTS
IDENTIFICATION DATA ...................424
▫ Vehicle Identification Number .............424
BRAKE SYSTEM ....................... .424
▫ Hydraulic Brake Assist ...................425
WHEEL AND TIRE TORQUE SPECIFICATIONS . .425
▫ Torque Specifications ....................425
FUEL REQUIREMENTS ...................428
▫ 6.4L Engine .......................... .428
▫ Reformulated Gasoline ..................428
▫ Materials Added To Fuel .................428 ▫
Gasoline/Oxygenate Blends ...............429
▫ Do Not Use E-85 In Non-Flex Fuel Vehicles . . . .429
▫ CNG And LP Fuel System Modifications ......430
▫ MMT In Gasoline ...................... .430
▫ Fuel System Cautions ....................430
▫ Carbon Monoxide Warnings ...............431
FLUID CAPACITIES ..................... .432
FLUIDS AND LUBRICANTS ................433
▫ Engine ............................. .433
▫ Chassis ............................ .435
9
IDENTIFICATION DATA
Vehicle Identification Number
The Vehicle Identification Number (VIN) is found on the
left front corner of the instrument panel, visible through
the windshield. This number also appears on the vehicle
frame and underbody as well as the Automobile Informa-
tion Disclosure Label affixed to a window on your vehicle,
the vehicle registration and title.
NOTE:It is illegal to remove or alter the VIN.
BRAKE SYSTEM
If power assist is lost for any reason (for example, repeated
brake applications with the engine off), the brakes will still
function. However, you will experience a substantial in-
crease in braking effort to stop the vehicle.
If either the front or rear hydraulic system loses normal
braking capability, the remaining system will still function
with some loss of overall braking effectiveness. This will be
evident by increased pedal travel during application,
greater pedal force required to slow or stop, and activation
of the “Brake Warning Light” and the “ABS Warning
Light” (if equipped) during brake use.
The brake system power assist is provided by a hydro-
boost unit which shares fluid with the power steering
system. You may experience some clicking or hissing
noises from the hydro-boost system during hard braking
conditions.
NOTE:Under cold temperatures, pedal effort will be
higher than normal until the power steering fluid reaches
operating temperature.
Vehicle Identification Number
424 TECHNICAL SPECIFICATIONS
Hydraulic Brake Assist
The brake system power assist is provided by a hydro-
boost unit which shares fluid with the power steering
system. You may experience some clicking or hissing
noises from the hydro-boost system during hard braking
conditions.
NOTE:Under cold temperatures, pedal effort will be
higher than normal until the power steering fluid reaches
operating temperature.
WHEEL AND TIRE TORQUE SPECIFICATIONS
Proper lug nut/bolt torque is very important to ensure that
the wheel is properly mounted to the vehicle. Any time a
wheel has been removed and reinstalled on the vehicle, the
lug nuts/bolts should be torqued using a properly cali-
brated torque wrench using a high quality six sided (hex)
deep wall socket.
Torque Specifications
Lug Nut/
Bolt Torque Lug Nut/
Bolt Type **Lug Nut/
Bolt Size Lug Nut/
Bolt Socket Size
120-150 Ft- Lbs (160-
200 N·m) Cone M14 x 1.50 22 mm
130-160 Ft- Lbs (190-
220 N·m) Flanged
**Use only your authorized dealer recommended lug nuts/
bolts and clean or remove any dirt or oil before tightening.
Inspect the wheel mounting surface prior to mounting the
tire and remove any corrosion or loose particles.
9
TECHNICAL SPECIFICATIONS 425
Chassis
ComponentFluid, Lubricant, or Genuine Part
Automatic Transmission (6.4L Engine with 66RFE Trans-
mission) (For Diesel Engine See Diesel Supplement) Use only ATF+4 Automatic Transmission Fluid. Failure to
use ATF+4 fluid may affect the function or performance of
your transmission. We recommend Mopar ATF+4 fluid.
Automatic Transmission (6.4L Engine with AS66RC Trans-
mission) Use only Mopar ASRC Automatic Transmission Fluid or
equivalent. Failure to use the proper fluid may affect the
function or performance of your transmission.
Transfer Case We recommend you use Mopar BW44-44 Transfer Case
Fluid.
Front and Rear Axle Fluid (4500/5500) We recommend you use GL-5 SAE 75W-90 Synthetic (MS-
9763). Limited slip additive is not required for Limited-Slip
Rear Axles.
Brake Master Cylinder We recommend you use Mopar DOT 3 and SAE J1703. If
DOT 3 brake fluid is not available, then DOT 4 is accept-
able.
Power Steering Reservoir We recommend you use Mopar Power Steering Fluid +4,
Mopar ATF+4 Automatic Transmission Fluid.
9
TECHNICAL SPECIFICATIONS 435