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CLUTCH FLUID/LINKAGE ADJUSTMENTS
Clutch fluid (if equipped)
During normal operation, the fluid level in the clutch reservoir should
remain constant. If the fluid level drops, fill to step in the reservoir.
1. Set the parking brake, shift into 1
(First) and turn the engine off.
2. Open the hood.
3. Clean the reservoir cap before
removal to prevent dirt and water
from entering the reservoir.
4. Remove cap and rubber
diaphragm from reservoir.
5. Add fluid, if necessary, until it
reaches the step in the reservoir.
6. Reinstall rubber diaphragm and cap onto reservoir.
Use only a DOT 3 brake fluid designed to meet manufacturer
specifications. Refer toLubricant specificationsin this chapter.
WARNING:Carefully read cautionary information on product
label. For MEDICAL EMERGENCY INFORMATION, contact a
physician or Poison Control Center immediately; on Ford-Motorcraft
products call: 1-800-959-3673 (FORD). Failure to follow these
instructions may result in personal injury.
Refer to theScheduled Maintenance Guidechapter for service interval
schedules.
Clutch linkage (if equipped)
Lubricate the clutch linkage using the following procedure. Use a grease
which meets manufacturer specifications. Refer toLubricant
specificationsin this chapter.
1. Set the parking brake, shift into 1 (First) and turn the engine off.
2. Remove the inspection cover from the clutch housing.
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Transmission and clutch
removed for clarity
3. Lubricate the clutch release bearing (at one location) and the clutch
release shaft (at two locations), using the grease fittings provided, with a
grease gun.
4. Lubricate clutch release wear pads at the two locations where they
contact the clutch release bearing with a brush or similar tool.
5. Install the inspection cover onto the clutch housing.
Refer to theScheduled Maintenance Guidechapter for the service
interval schedules.
TRANSMISSION FLUID
Automatic transmission fluid
Refer to yourAllison Automatic Transmission Operator’s Manualfor
scheduled transmission fluid check/change intervals. Your transmission
does not consume fluid. However, the fluid level should be checked if the
transmission is not working properly, i.e., if the transmission slips or
shifts slowly or if you notice some sign of fluid leakage.
Automatic transmission fluid expands when warmed. To obtain an
accurate fluid check, drive the vehicle until it is warmed up
(approximately 20 miles [30 km]). If your vehicle has been operated for
an extended period at high speeds, in city traffic or during hot weather,
the vehicle should be turned off for about 30 minutes to allow fluid to
cool before checking.
1. Drive the vehicle 20 miles (30 km) or until it reaches normal operating
temperature.
2. Park the vehicle on a level surface and engage the parking brake.
3. With the parking brake engaged and your foot on the brake pedal,
start the engine and move the gearshift lever through all of the gear
ranges. Allow sufficient time for each gear to engage.
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4. Place the gearshift lever in N (Neutral) or P (Park) and leave the
engine running.
5. Remove the dipstick, wiping it clean with a clean, dry, lint-free rag.
6. Install the dipstick, making sure it is fully seated in the filler tube.
7. Remove the dipstick and inspect the fluid level.
If you must add transmission fluid, refer to yourAllison Automatic
Transmission Operator’s Manualfor the correct fluid type.Use of a
non-approved automatic transmission fluid may cause internal
transmission component damage.
Fluid levels above the safe range may result in transmission failure; an
overfill condition of transmission fluid may cause shift and/or
engagement concerns and/or possible damage.
Eaton UltraShift (if equipped)
The Eaton UltraShift transmission is filled with synthetic fluid from the
factory with no scheduled fluid change intervals as this fluid is intended
to last the life of the transmission. However, the system should be
checked regularly to ensure that proper transmission fluid levels remain
constant. Refer to theEaton Driver Instructions Manualfor details.
Manual transmission fluid
Refer to theScheduled Maintenance Guidechapter for transmission
fluid level check/change intervals.
Your manual transmission may be filled with an optional synthetic fluid
which allows the use of extended service intervals. A tag on the filler
plug identifies the use of the synthetic fluid.
Only use fluid that meets manufacturer specifications; refer toLubricant
specificationsin this chapter.Use of a non-approved transmission
fluid may cause internal transmission component damage.
Check your transmission fluid level using the following procedure:
1. Park the vehicle on level ground.
2. Set the parking brake and shift into 1 (First) and turn the engine off.
3. Clean any dirt from around the filler plug.
4. Remove the filler plug and inspect the fluid level; the fluid level should
be at the bottom of the filler plug opening.
5. Add fluid, if necessary, through the filler plug opening.
6. Clean and install the filler plug securely.
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Drain and refill your transmission fluid, while it is warm, using the
following procedure:
1. Park the vehicle on level ground.
2. Set the parking brake and shift into 1 (First) and turn the engine off.
3. Clean any dirt from around the filler and drain plugs.
4. Remove the filler and drain plugs and drain the fluid into a suitable
container. Dispose all used automotive fluids in a responsible manner
following your local authorized standards.
5. Clean and install the drain plug securely.
6. Add fluid through the filler plug opening.
7. Clean and install the filler plug securely.
CHASSIS-MOUNTED CHARGE AIR COOLER
Inspect charge air cooler daily
Visually inspect the core assembly for debris and clogging of external fins
with the engine off. Prior to engine operation, remove any debris
blocking the core.
•Turbocharger-to-charge air cooler
•Charge air cooler-to-intake manifold pipe
•Mounting bracket
•Chassis-mounted charge air cooler core
Inspect air intake piping
•Check for accumulation of salt deposits (where applicable). If present,
disassemble and clean the complete air intake piping system. If the
intake piping is pitted, use MotorcraftSilicone Gasket and Sealant
TA-30 to seal joints against leakage.
•Check for loose hoses and clamps.
•Check for ruptured or collapsed hoses.
•Check air cleaner housing for cracks.
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ELECTRICAL SYSTEM INSPECTIONS
Periodically inspect electrical connectors on the outside of the cab, and
on the engine and frame for corrosion and tightness. Exposed terminals
such as the fuel sender, cranking motor, alternator and feed-through
studs should be cleaned and re-coated with a lubricant sealing grease
such as MotorcraftSilicone Brake Caliper Grease and Dielectic
Compound XG-3, or equivalent. This should include the ground cable
connector for batteries, engine and cab as well as the jump starting stud.
Accessory feed connections
Vehicle electrical systems are complex and often include powertrain
components such as engine and transmission controls, instrument panels,
ABS, etc. While most systems operate on battery voltage (12 volts),
some systems can be as high as 90 volts or as low as 5 volts. Refer to the
Electrical Circuit Diagram Manuals, available from your vehicle’s
manufacturer, to ensure that any additional body lights and accessories
are connected to circuits that are both appropriate and not overloaded.
No modification should be made to any vehicle control system without
first contacting your dealer.
SUSPENSION INSPECTION
Note:Do not adjust air suspension height to any setting other than the
specified setting. Altering the height setting changes the driveline angle
and may result in unwarrantable component damage, such as
transmission component damage.
Verify drive axle air suspension height and height control valve
performance at engine oil change intervals.
Periodically check:
•
Condition of spring leaves for evidence of fatigue, bending or breakage.
•Condition of suspension mounting brackets and bushings.
•Torque rod mounting fasteners for tightness.
•For proper suspension alignment; this must be maintained at all times.
•U-bolts after the chassis has been operating under load for 1,000 miles
(1,600 km) or six months (whichever comes first), the U-bolt nuts
must be re-torqued. The U-bolt nuts must be re-torqued every
36,000 miles (58,000 km) thereafter. The U-bolt and nut threads and
seats should be cleaned and lubricated to ensure a “like new”
condition when re-torquing.
Note:See theU-bolt nut torquechart later in this section.
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Supporting your vehicle for service
Prepare the vehicle for service repairs by doing the following:
1. Park the vehicle on a level concrete floor.
2. Set the parking brake and block the wheels to prevent the vehicle
from moving.
3. Select a jack with a rated capacity sufficient to lift and hold up the
vehicle.
4. Raise the vehicle with the jack applied to the axle(s). DO NOT use the
bumper as a lifting point.
5. Support the vehicle with floor stands under the axle(s). If the axle or
the suspension are being serviced, support the vehicle with floor stands
under the frame side-members, preferably between the axles.
WARNING:Do not use a jack when working under a vehicle. It
may give way, causing the vehicle to fall and result in property
damage, personal injury or death. Always use floor stands to support
the vehicle.
FRAME AND TOW HOOKS
Your vehicle’s chassis is manufactured with frame rails of either HSLA
steel or heat-treated steel; each must be handled in a specific manner to
ensure maximum service life. Consult the service manual or your dealer
before attempting frame repair or modification.
It is important, particularly on vehicles where the tow hooks are used
frequently, to inspect the front and rear tow hooks for damage or a loose
mounting.
SPRING U-BOLT CHECKS
Check U-bolt nuts and re-torque every 36,000 miles (58,000 km) after
initial 1,000 miles (1,600 km) re-torque. The U-bolt and nut threads and
seats should be cleaned and lubricated to ensure peak condition when
re-torqued.
U-bolt nut torque
Suspension ft-lb N•m
Front axle – 8500 lb (3856 kg) 180-200 244-271
Front axles – 10000 lb (4536 kg) and higher 260-300 353-407
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Suspension ft-lb N•m
Rear axle with multi-leaf 260-300 353-407
Rear axle with IROS air suspension 370-400 502-542
Rear axle with Hendrickson air suspension 400–450 542–610
See air suspension U-bolt re-torquing and installation information below.
Air suspension U-bolt checks and re-torquing procedures
1. Inspect the threads of the U-bolt and nut for rust and debris. Clean
the threads if contaminated.
2. Using a torque wrench, determine if any nuts can be turned with a
force below the specified torque.
3. Using the lowest discovered torqued nut as a starting point, retighten
the nuts using the sequence listed underAir suspension U-bolt and
U-bolt nut installation.
Air suspension U-bolt and U-bolt nut installation
1. Inspect the threads of the U-bolt and nut for rust and debris. Clean
the threads if contaminated.
2. Install the U-bolts and nuts and torque the nuts to seat the cap flat
which is about 18 ft-lb (25 N•m) using a diagonal pattern. Use the same
diagonal pattern for each of the following U-bolt nut re-torque steps.
3. Tighten U-bolt nuts in increments of 74 ft-lb (100 N•m) until
tightened to final torque for the particular suspension.
DRIVESHAFT
Check the universal joints for any evidence of wear or looseness at the
regular lubrication interval. Stop the vehicle immediately, should
driveshaft vibrations occur, to avoid possible hazardous consequences or
damage to other components.
REAR AXLE LUBRICANT
Refer to theScheduled Maintenance Guidechapter for rear axle
lubricant level check/change intervals.
Your rear axle may be filled with an optional synthetic lubricant which
allows the use of extended service intervals. A tag on the filler plug
identifies the use of the synthetic lubricant.
Only use a lubricant that meets manufacturer specifications; refer to
Lubricant specificationsin this chapter.Use of a non-approved rear
axle lubricant may cause internal axle component damage.
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Checking the rear axle lubricant level
1. Park the vehicle on level ground.
2. Set the parking brake and shift into N (Neutral) (automatic
transmission) or 1 (First) (manual transmission) and turn the engine off.
3. Clean any dirt from around the rear axle filler plug.
4. Remove the filler plug and inspect the lubricant level; it should be up
to the bottom of the filler plug opening.
5. Add lubricant, if necessary, through the filler plug opening.
6. Clean and install the filler plug securely.
Draining and refilling the rear axle lubricant
1. Drain the rear axle while the lubricant is warm.
2. Park the vehicle on level ground.
3. Set the parking brake and shift into N (Neutral) (automatic
transmission) or 1 (First) (manual transmission) and turn the engine off.
4. Clean any dirt from around the rear axle filler and drain plugs.
5. Remove the filler and drain plugs and drain the lubricant into a
suitable container. Dispose of all used automotive fluids in a responsible
manner following your local authorized standards.
6. Clean and install the drain plug securely.
7. Add lubricant through the filler plug opening.
8. Clean and install the filler plug securely.
WHEELS
General
Wheel bearings should be inspected, lubricated and adjusted at regular
intervals. This is especially important if operating in deep sand, mud or
water. Refer toLubricant specificationsin this chapter.
Mount wheel balance weights on the dome-side of the wheel only; failure
to do so may result in loss of wheel weight and/or damage to brakes or
wheels.
Important:Remember to replace the wheel air valves when the road
tires are replaced at the end of their useful life.
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