
Check to make sure that the axle mounting U-bolt nuts, attaching or
mounting bolts and nuts are securely tightened. Regularly check front
axle for damage, binding, worn parts and adequate lubrication.
At regular intervals, or during other scheduled maintenance, (tire
rotation/service, wheel bearing service, alignment, etc.) the kingpins
should be checked for excessive wear. Refer to the service manual for
proper procedures.
Toe-in setting - general inspection
Inspecting steer axle tires in the first 3,000–10,000 service miles
(4,800–16,000 service km) will generally show if tires are wearing
normally.
Rapid outside shoulder wear on both tires indicates too much toe-in.
Rapid inside shoulder wear on both tires indicates too much toe-out. In
P&D-type service, left-to-right steer tire tread life differentials up to 40%
can be observed depending on routes and other variables.
Follow the tire manufacturer’s recommended cold inflation pressure for
the tire size, load range (ply rating) and steer axle loading typical for
their operation (each steer axle tire will equal
1⁄2steer axle loading).
Special applications may warrant a setting based on past experience with
the type of tire operating loads and conditions. Radial tires are more
sensitive to toe-in setting than bias ply tires. While not insensitive to
vehicle alignment, fine tuning school bus alignment to line-haul truck
standards will not drastically improve tire tread life.
It is essential that correct toe-in and tire pressure be maintained for
optimum tire wear.
Rear axle - general inspection
Check to make sure that the axle mounting U-bolts, attaching or
mounting bolts and nuts are securely tightened. Refer toU-bolt nut
torque chartin this chapter. Regularly check the rear axle for damaged,
binding or worn parts.
NoSpin Detroit Locker positive locking differential
Vehicle equipped with this type differential have the operator’s manual
supplied with the vehicle. Refer to this manual for maintenance checks.
Brake system - general inspection
Your vehicle is equipped with non-asbestos brake linings. However,
exposure to excessive amounts of brake material (whether asbestos or
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POWER STEERING FLUID
Check the power steering fluid level using the following procedure. Refer
to the general maintenance information section for the recommended
service intervals. If adding fluid is necessary, use only MERCONAT F.
1. Set the parking brake, shift into N (Neutral) (automatic transmission)
or 1 (First) (manual transmission) and turn the engine off.
2. Open the hood.
3. Clean the top of the power steering fluid reservoir.
4. Remove the dipstick from the reservoir and wipe the dipstick clean.
5. Reinstall the dipstick. Remove it again and check the fluid level.
•If the fluid temperature is at
approximately 68°F - 120°F (20°C
-49°C) (fluid cool or warm to
the touch), check the COLD side
of the dipstick. The fluid level
should be within the FULL range
•If the fluid level is below the ADD
line, add fluid in small amounts,
continuously checking the level until it reaches the proper level.
•If the fluid temperature is at
approximately 176°F–230°F
(80°C - 110°C) (fluid too hot to
touch), check the HOT side of
the dipstick. The fluid level
should be within the FULL range.
•If the fluid level is below the ADD
line, add fluid in small amounts,
continuously checking the level until it reaches the proper level.
Note:The fluid level may also be checked by looking at the see-through
plastic reservoir. Make sure that the fluid is within the minimum and
maximum fluid range as marked on the reservoir.
A low fluid level may indicate a leak in the power steering system.
Inspect the power steering system and repair the leak. If necessary, see
your dealer or a qualified service technician.
To avoid damage to the power steering system,do notoperate the
vehicle with a low power steering fluid level.
Whenever the dipstick is installed, make sure it is properly seated and
tightened securely.
ADD MAX. COLDFULL
ADD MAX. HOTFULL
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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.
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, make sure the correct type of fluid is
being used. The type of fluid used is indicated in your Allison Automatic
Transmission Operator’s Manual.
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.
Use of a non-approved automatic transmission fluid may cause
internal transmission component damage.
Manual transmission fluid
Refer to your general maintenance information section for transmission
fluid level checks and fluid 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 will identify the use of the synthetic fluid.
Use only fluid that meets manufacturer specifications (refer to
Lubricant 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.
5. The fluid level should be up to the bottom of the filler plug opening.
6. If necessary, add enough fluid through the filler plug opening so that
the fluid level is at the bottom of the opening.
7. Clean and install the filler plug securely.
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Drain and refill your transmission fluid using the following procedure:
1. Drain the transmission while the fluid is warm.
2. Park the vehicle on level ground.
3. Set the parking brake and shift into 1 (First) and turn the engine off.
4. Clean any dirt from around the filler and drain plugs.
5. 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.
6. Clean and install the drain plug securely.
7. Add enough fluid through the filler plug opening so that the fluid level
is up to the bottom of the opening.
8. Clean and install the filler plug securely.
ENGINE AND SUBSYSTEM MAINTENANCE
Note:Information in this section pertains to the 6.0L Power Stroke
engine only. For information pertaining to other engines, see the
respective engine operator manual.
Note:To prevent damage to the engine control module, never
spray-wash it directly. Never spray any connector.
For effective emissions control and low operating cost, it is important
that maintenance operations listed in this section be performed at the
specified periods or mileage intervals indicated (kilometers, miles, hours,
or months, whichever comes first).
Service intervals are based upon average operating conditions. Where
dusty, frequent start and stop or heavily laden operations are
encountered, more frequent servicing will be required.
As the vehicle (engine) owner, you are responsible for the performance
of all scheduled maintenance. The required maintenance operations may
be performed by the owner at a service establishment of the owner’s
choosing. Any replacement parts used for required maintenance services
or repairs should be genuine manufacturer service parts or equivalent in
quality and performance to genuine manufacturer service parts. Use of
inferior parts hinders operations of the engine and emissions controls
and can reduce engine life and/or jeopardize the warranty.
Receipts covering the performance of regular maintenance should be
retained in the event questions arise concerning maintenance. The
receipts should be transferred to each subsequent owner of the vehicle
(engine).
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REAR AXLE LUBRICANT
Refer to your general maintenance information section for rear axle
lubricant level checks and lubricant 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 will
identify the use of the synthetic lubricant.
Use only 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.
Check your rear axle lubricant level using the following procedure:
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.
5. The lubricant level should be up to the bottom of the filler plug
opening.
6. If necessary, add enough lubricant through the filler plug opening so
that the lubricant level is at the bottom of the opening.
7. Clean and install the filler plug securely.
Drain and refill your rear axle lubricant using the following procedure:
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 all used automotive fluids in a responsible
manner following your local authorized standards.
6. Clean and install the drain plug securely.
7. Add enough lubricant through the filler plug opening so that the
lubricant level is up to the bottom of the opening.
8. Clean and install the filler plug securely.
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