GENERAL INFORMATION
WARNING: Exceeding these ratings
by overloading can cause component
failure resulting in property damage,
personal injury or death.
Fluid Temperature
If the operating temperature exceeds
250°F (121°C), the rate of axle lubrication
oxidation increases and shortens the life
of the lubricant and seals, requiring axle
lubrication changes to become more
frequent to preserve the axle. Do not
consistently run extreme pressure (EP)
lubricants above 250°F (121°C).
Axle Conversions
WARNING: When operating a
loaded vehicle, the driver must keep all
adjustable axles on the ground at all
times, supporting their share of the
vehicle’s load. Failure to do so can
overload other axles, tires, wheels,
springs, steering components, brakes
and frames, resulting in early component
failure, loss of vehicle control, possible
property damage and personal injury.
We do not recommend, or approve,
performing axle conversions. However, we
understand that, on occasion, others install
aftermarket add-on axles on the truck
chassis that allow operator control for
weight transfer from other axles (such as
air lift axles).
2-SPEED REAR AXLE (IF EQUIPPED)
WARNING: Never shift a
two-speed axle when descending a
steep grade as this may cause loss of
vehicle control and result in personal
injury.
Note:Do not shift between ranges when
the speed control is on.
A two-speed rear axle allows the driver to
select a low range for greater pulling power
and a high range for greater road speed
and fuel economy. You can also use these
ranges to provide extra steps between
transmission shifts when driving on steep
grades or fuel economy may be factors.
Axle Shifting
E208228
Note:Do not shift the axle to LOW when
your vehicle is moving. Use LOW when you
drive a fully loaded vehicle on a severe grade
or in congested traffic. Use HIGH for all
normal driving conditions with a lightly
loaded or partially loaded vehicle.
Note:The axle is set to HIGH by default.
To shift the axle between HIGH and LOW
with the vehicle stopped, place the
transmission in position N, then press and
hold the button for two seconds.
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Rear Axle
VEHICLE INSPECTION
INFORMATION
To make sure your vehicle is ready to
operate, conduct a pre-trip inspection at
the beginning of each work period. Follow
the steps listed in this section to verify a
proper vehicle inspection procedure.
WARNING: Exercise great caution
when working on a vehicle equipped with
an automatic fan clutch. The fan starts
in motion only after the engine coolant
reaches a predetermined temperature
or the refrigerant pressure (if equipped
with air conditioning) reaches a
predetermined setting. The fan starts at
this point with no advance warning.
Never reach near, or permit objects to
protrude into, the fan blade radius while
the engine is running as this could result
in vehicle damage, personal injury or
death.
WARNING: Do not operate the
vehicle if any suspension conditions
listed in the following charts are evident.
Loss of steering or suspension could
result in property damage, personal injury
or death.
WARNING: If a wheel must be
changed, obtain expert tire service help.
Mounting and un-mounting of tires
should only be performed by a qualified
technician using necessary safety
procedures and equipment, otherwise
the result could be property damage,
personal injury or death.
Note:Always make sure you apply the
parking brake before starting the engine.
Engine compartment (with engine off)
Use the dipstick to verify the oil level is in the proper operating
range. See Engine Oil Dipstick (page 224). Engine oil
Look through the plastic reservoir and verify the coolant level
is within the proper operating range. Do not remove the
pressure cap until the coolant has cooled. See Engine
Coolant Check (page 238). Engine coolant
Verify that the fluid level is in the proper operating range. See
Power Steering Fluid Check (page 245). Power steering fluid
Remove the master cylinder caps and inspect the fluid level.
See Brake Fluid Check (page 244). Brake fluid
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Vehicle Inspection Guide
Engine compartment (with engine off)
Inspect for glazing, fraying or cracking. There should be no
more than 5-7 cracks per rib, per 1 in (2.5 cm) Belts (fan, alternator,
water pump and air
conditioning
compressor)
Inspect for signs of fluid puddles or dripping fluid on the
ground under the engine, or the underside of the engine. Fluid leaks
Inspect for debris that may have collected on the HVAC air
inlet grille or inside the exterior module as this may reduce
system performance. HVAC air inlet
Engine starting (with parking brake applied)
Before entering the cab, verify that the vehicle is equipped
with spare electrical fuses (if used), three red reflective
triangles, a properly charged and rated fire extinguisher and
wheel chocks. Safety and emergency
equipment
Walk around the vehicle and verify all steps and grab handles,
inside and out (as well as behind), are tight and clean. Use
extreme caution and a three-point stance at all times.
Inspect door latches for proper closing, latching and locking.
Set the parking brake. Make sure the gearshift lever is in
neutral (N) or park (P) (if equipped with a park position). Starting the engine
Diesel engine: Turn the key to the on position. Turn the key
to start when the wait to start indicator light in the instrument
cluster turns off.
Gasoline engine: Turn the key to start, and then release it
as soon as the engine starts.
Verify pressure builds to normal operating range. Engine oil pressure
A tone indicating low air pressure should sound immediately
after the engine starts but before the compressor has built-
up pressure. The tone should stop when the air pressure
reaches 70 psi (483 kPa). Let the air pressure build to
governed cutout pressure, which should occur between
115–130 psi (793–896 kPa). Low air pressure warning
tone (if equipped with an
air compressor)
Press the accelerator and verify that it operates smoothly,
without any binding or irregular feel. Release the pedal and
verify the engine returns to idle speed immediately. Accelerator
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Vehicle Inspection Guide
Engine starting (with parking brake applied)
Check the gauge (diesel engine) or indicator light (gasoline
engine) to verify the alternator is charging. Voltmeter
Inspect for excessive free play in the steering linkages. The
steering wheel should have less than 2 in (5 cm) of free play
at its rim. Steering linkage free play
Verify the parking brake holds the vehicle by gently trying to
pull forward with the parking brake applied. Parking brake
Verify operation using the following procedure. Chock the
wheels, if necessary. Push in the parking brake and, on
tractors, push in the tractor parking brake knob: Air brakes
1. Verify the air compressor or governor cutout pressure is
approximately 120 psi (827 kPa).
2. Turn off the engine, and then turn the key back to the on
position (without starting the engine).
3. Without the brake pedal applied, note the air pressure drop
for one minute. It should be less than 2 psi (14 kPa) for single
vehicles and 3 psi (21 kPa) for combination vehicles.
4. Press and hold the brake pedal with 90 psi (621 kPa) or
more. Make sure there is no more than a 3 psi (21 kPa) per
minute leak for single vehicles and a 4 psi (28 kPa) minute
leak for combination vehicles.
5. Pump the brake pedal to deplete the system of air pressure.
The warning light and tone should turn on at 57 psi (393 kPa).
6. Pump the brake pedal and make sure the parking brake
and trailer parking brake knobs pop out at 20 psi (138 kPa)
or higher.
Verify that the fluid level is in the proper operating range. See
Automatic Transmission Fluid Check (page 242). Automatic transmission
fluid
Front of vehicle
Verify all exterior lights illuminate and are clean. Lights
Check headlights function on high and low beam.
Verify reflectors are clean, unbroken and of proper color (red
on rear, amber elsewhere).
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Vehicle Inspection Guide
Front of vehicle
Verify running lights are clean and unbroken.
Inspect for any missing or loose fasteners, power steering
fluid leaks and damage to power steering hoses. Steering gear
Verify connecting links, arms and rods are not worn or cracked. Steering linkage
Verify joints, sockets and boot seals are not worn or loose.
Verify cotter keys, nuts and bolts are not loose or missing.
Inspect front and rear tow hooks for damage or loose
mounting. This is particularly important on vehicles that use
them frequently. Tow hooks
Front suspension
Inspect for missing, broken or shifted leaves, or leaves that
may be in contact with (or nearly contacting) a tire, rim, brake
drum, frame or body component. Springs
Note: Never apply grease to spring pads.
Make sure there the following items are properly tightened
and that there are no cracks, breaks, wear, damage to spring
hangers, bolts, bushings, axle mounting bolts, and nuts. Spring mounts
Inspect for any cracks, leaks, or missing or broken bolts or
bushings. Shock absorbers
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Vehicle Inspection Guide
Diesel Exhaust Fluid (DEF) area
Verify the tanks and caps are secure and that there are no
leaks from the tanks. DEF tanks
Inspect for leaks from the tanks. Leaks
Underbody
Verify that the driveshaft is not bent or cracked and that all
driveshaft couplings are secure. Driveshaft
Verify that the visible outside parts are securely mounted and
that there are no cracks, holes or severe dents. Exhaust system
Inspect for cracks or bends in longitudinal frame members.
Verify there are no loose, cracked, bent, broken or missing
crossmembers or crossmember fasteners. Frame
Rear of vehicle
Verify there are no cuts, cracks, chafing or wear on the air
hoses and electrical line insulation. Listen for audible air leaks. Air hoses and electrical
lines
Verify air and electrical lines are not tangled, crimped or
pinched or being dragged against any truck parts. None of
the air or electrical line should be spliced or taped.
Inspect for corrosion on pins and in electrical sockets to verify
continuity and reduced heat build-up potential.
Verify the deck plate is clean, bolted securely to the frame
and is clear of loose objects. Deck plate
Verify that both brake lights illuminate when the pedal is
applied, each signal flashes and that the four-way flashers
work properly. Turns signals, brake
lights and flashers
Verify all exterior lights illuminate and are clean. Lights and reflectors
Verify reflectors are clean, unbroken and of proper color (red
on rear, amber elsewhere).
Verify running lights are clean and unbroken.
Note: Inspect rear running lights separately from signal,
flasher and brake lights.
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Vehicle Inspection Guide
GENERAL INFORMATION
WARNING: Making modifications
to various parts, components and
systems of the vehicle, such as brake and
steering systems, can adversely affect
the quality, reliability and operation of
your vehicle and could result in property
damage, personal injury or death. Such
modifications must be avoided.
WARNING: Failure to properly
perform maintenance and servicing
procedures could result in vehicle
damage, personal injury or death.
WARNING: Take care when
performing any maintenance, system
check or service on your vehicle. Some
of the materials may also be hazardous
if used, serviced or handled improperly
and could result in property damage,
personal injury or death.
If the owner or operator of the vehicle is a
skilled technician and intends on
performing the vehicle maintenance and
service, he is strongly urged to purchase a
service manual.
Always use care when performing vehicle
maintenance, repairs or system checks.
Improper or incomplete service could result
in your vehicle not working properly which
may result in personal injury or damage to
your vehicle or equipment. It is the
operator’s responsibility to see that your
vehicle receives proper care and
maintenance. If you have any questions
about performing service, have the service
done by a qualified technician.
To help you service your vehicle, we
provide scheduled maintenance
information which makes tracking routine
service easy. See Scheduled
Maintenance (page 319).If your vehicle requires professional service,
an authorized dealer can provide the
necessary parts and service. Check your
warranty information to find out which
parts and services are covered.
Use only recommended fuels, lubricants,
fluids and service parts conforming to
specifications. Motorcraft® parts are
designed and built to provide the best
performance in your vehicle.
Servicing Guidelines
WARNING: The use of inferior parts
can adversely affect the quality and
reliability of your vehicle and could result
in property damage, personal injury or
death.
When servicing your vehicle:
• Always wear safety glasses for eye
protection.
• Always set the parking brake or chock
the wheels.
• Always use support stands, not a jack,
when working under a raised vehicle.
• Always turn off the ignition unless a
procedure requires the engine to be
running.
• Always avoid contact with hot metal
parts. Allow the components to cool
before working with, or around, them.
• Always operate the engine in a
well-ventilated area.
• Do not wear loose-fitting clothing,
hanging jewelry, watches or rings.
• Do not smoke.
• Do not work on the brakes or the clutch
unless you take the proper precautions
to avoid inhaling friction material dust.
219
Maintenance
UNDER HOOD OVERVIEW - 6.7L DIESEL
E313700E313700
Engine compartment fuse box. See Fuses (page 200). A
Windshield washer fluid reservoir. See Washer Fluid Check (page 249). B
Automatic transmission fluid dipstick. See Automatic Transmission Fluid
Check (page 242). C
Secondary Cooling System Reservoir. See Engine Coolant Check (page 233). D
Engine coolant reservoir. See Engine Coolant Check (page 233). E
Secondary fuel filter. See Draining the Fuel Filter Water Trap (page 232). F
Engine oil separator. See Changing the Engine Oil and Oil Filter (page 226). G
Engine oil filler cap. See Engine Oil Check (page 224). H
Brake fluid reservoir. See Brake Fluid Check (page 244). I
Power steering fluid reservoir. See Power Steering Fluid Check (page 245). J
Air brake compressor. See Brake System Inspection (page 255). K
Engine oil dipstick. See Engine Oil Dipstick (page 224). L
Air cleaner assembly. See Changing the Engine Oil and Oil Filter (page 226). M
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Maintenance