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D. Maintain coolant concentration at 50% HOAT ethyl-
ene glycol engine coolant (minimum) and distilled water
for proper corrosion protection of your engine.
E. Make sure that the radiator and coolant bottle over-
flow hoses are not kinked or obstructed.
F. Keep the front of the radiator clean. If your vehicle is
equipped with air conditioning, keep the front of the
condenser clean also.
G. The thermostat should not be changed for summer or
winter operation. If replacement is ever necessary, install
ONLY the correct type thermostat. Other designs may
result in unsatisfactory cooling performance.
Emission Related Components
Fuel System Hoses And Vapor/Vacuum Harnesses
When the vehicle is serviced for scheduled maintenance,
inspect surface of hoses and nylon tubing for evidence of
heat and mechanical damage. Hard and brittle rubber,cracking, checking, tears, cuts, abrasions, and excessive
swelling suggest deterioration of the rubber. Particular
attention should be given to examining hose surfaces
nearest to high heat sources, such as the exhaust mani-
fold.
Insure nylon tubing in these areas has not melted or
collapsed.
Inspect all hose clamps and couplings to make sure they
are secure and no leaks are present.
NOTE:Fluids such as oil, power steering fluid, and
brake fluid are used during assembly plant operations to
ease the assembly of hoses to couplings. Therefore, oil
wetness at the hose-coupling area is not necessarily an
indication of leakage. Actual dripping of hot fluid when
systems are under pressure (during vehicle operation),
should be noted before hose is replaced based on leakage.
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You are urged to use only the manufacturer’s specified
hoses and clamps, or their equivalent in material and
specification, in any fuel system servicing. It is manda-
tory to replace all clamps that have been loosened or
removed during service. Care should be taken in install-
ing new clamps to insure they are properly torqued.
Positive Crankcase Ventilation (PCV) Valve
Proper operation of the crankcase ventilation system
requires that the PCV valve be free of sticking or plug-
ging because of deposits. Deposits can accumulate in the
PCV valve and passage with increasing mileage. Have
the PCV valve, hoses, and passages checked for proper
operation at the intervals specified. If the valve is
plugged or sticking, replace with a new valve –Do not
attempt to clean the PCV valve!Check ventilating hose
for indication of damage or plugging with deposits.
Replace if necessary.
Brake System
Power Disc Brakes (Front)
Disc brakes do not require adjustment; however, several
hard stops during the break-in period are recommended
to seat the linings and wear off any foreign material.
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Brake Master Cylinders
The fluid level in the master cylinders should be checked
whenever the vehicle is serviced, or immediately if the
brake system warning light is on. If necessary, add fluid
to bring level to the full mark on the side of the reservoir
of the brake master cylinder. Be sure to clean the top of
the master cylinder area before removing the cap. With
disc brakes, fluid level can be expected to fall as the brake
pads wear. Brake fluid level should be checked when
pads are replaced. If the brake fluid level is abnormally
low, check system for leaks.
Refer to Recommended Fluids, Lubricants and Genuine
Parts for correct fluid type.WARNING!
Use of brake fluid that may have a lower initial
boiling point, or is unidentified, as to specifications
may result in sudden brake failure during hard
prolonged braking. You could have an accident.
WARNING!
Overfilling the brake fluid reservoir can result in
spilling brake fluid on hot engine parts and the
brake fluid catching on fire.
Use only brake fluid that has been in a tightly closed
container to avoid contamination from foreign matter or
moisture.
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CAUTION!
Do not allow a petroleum-base fluid to contaminate
the brake fluid. Seal damage may result.
Brake Hoses
Inspection should be performed whenever the brake
system is serviced or at intervals specified. Inspect hy-
draulic brake hoses for surface cracking, scuffing or worn
spots. If there is any evidence of cracking, scuffing, or
worn spots, the hose should be replaced immediately!
Eventual deterioration of the hose can take place with
possible burst failure.
WARNING!
Worn brake hoses can burst and cause brake failure.
You could have an accident. If you see any sign of
cracking, scuffing, or worn spots, have the brake
hoses replaced immediately.
Automatic Transmission
Fluid Level Check
Check the fluid level while the transmission is at normal
operating temperature 180°F (82°C). This occurs after at
least 15 miles (24 km) of driving. At normal operating
temperature the fluid cannot be held comfortably be-
tween the fingertips.
To check the automatic transmission fluid level properly,
the following procedure must be used:
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1. Operate the engine at idle speed and normal operating
temperature.
2. The vehicle must be on level ground.
3. Fully apply the parking brake and press the brake
pedal.
4. Place the gear selector momentarily in each gear
position ending with the lever in P (Park).
5. Remove the dipstick, wipe it clean and reinsert it until
seated.
6. Remove the dipstick again and note the fluid level on
both sides. The fluid level should be between the “HOT”
(upper) reference holes on the dipstick at normal operat-
ing temperature. Verify that solid coating of oil is seen on
both sides of the dipstick. If the fluid is low, add as
required into the dipstick tube.Do not overfill.After
adding any quantity of oil through the oil fill tube, waita minimum of two (2) minutes for the oil to fully drain
into the transmission before rechecking the fluid level.
NOTE:If it is necessary to check the transmissionbelow
the operating temperature, the fluid level should be
between the two “COLD” (lower) holes on the dipstick
with the fluid at approximately 70°F ( 21°C) (room
temperature). If the fluid level is correctly established at
room temperature, it should be between the “HOT”
(upper) reference holes when the transmission reaches
180°F ( 82°C). Remember it is best to check the level at the
normal operating temperature.
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CAUTION!
Be aware that 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.
7. Check for leaks. Release parking brake.
To prevent dirt and water from entering the transmission
after checking or replenishing fluid, make certain 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.
Automatic Transmission Fluid And Filter Change
It is important that proper lubricant is used in the
transmission. Refer to Recommended Fluids, Lubricants
and Genuine Parts for correct fluid type. It is importantthat the transmission fluid be maintained at the pre-
scribed level using the recommended fluid.
CAUTION!
Using a transmission fluid other than the manufac-
turers recommended fluid may cause deterioration
in transmission shift quality and/or torque converter
shudder. Using a transmission fluid other than the
manufacturers recommended fluid will result in
more frequent fluid and filter changes. Refer to
Recommended Fluids, Lubricants and Genuine Parts
for correct fluid type.
Special Additives
The manufacturer strongly recommends against the ad-
dition of any additives to the transmission. Exception to
this policy is the use of special dyes to aid in detecting
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fluid leaks. The use of transmission sealers should be
avoided, since they may adversely affect seals.
Transfer Case
Inspect the transfer case for fluid leaks. If a fluid leak is
evident the transfer case fluid level may be low. Have the
transfer case serviced immediately.
CAUTION!
Damage may result from operation of the vehicle
with low transfer case fluid.
The transfer case fluid should be drained and refilled at
the intervals specified.
Lubricant Selection
Refer to Recommended Fluids, Lubricants and Genuine
Parts for correct fluid type.
Axles
Refer to Recommended Fluids, Lubricants and Genuine
Parts for correct fluid type.
The manufacturer does not recommend regularly sched-
uled oil changes for axles in vehicles whose operation is
classified as normal truck service.
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.
Rear Axle
Rear Axle fluid levels should be 7/8(22 mm) below the
fill hole for 8 1/4axles, and 1 1/4(31 mm) below the fill
hole for 9 1/4axles.
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Front Axle
Front Axle fluid level should be 3/4” (20 mm) below the
bottom of the fill hole.
Selection of Lubricating Grease
The National Lubricating Grease Institute (NLGI) has
developed a symbol (Certification Mark) to aid the
vehicle owner in the proper selection of grease for chassis
components. This symbol, an example shown below, is
located on the grease container and identifies the appli-
cation and quality of the grease.There are two groups
identified, those for wheel
bearings (Letter “G”) and
those for chassis (Letter
“L”) lubrication. Perfor-
mance categories within
these groups result in dual
letter designations for
each group. The letter des-
ignations shown in the ex-
ample are the highest
quality level available and when combined as shown can
be used for chassis lubrication. Use only those greases
that have the NLGI symbol on the container along with
the proper quality level for your application.
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