
AUTOMATIC TRANSMISSION
FLUID CHECK
The transmission does not consume fluid.
However, the fluid level should be checked
if the transmission is not working properly,
for example if the transmission slips, shifts
slowly or if there are signs of fluid loss.
The transmission fluid and filter on your
vehicle must be replaced at the specified
service interval. See Scheduled
Maintenance (page 322).
Automatic transmission fluid expands
when warmed. To check the fluid level
consistently and accurately, do the
following:
1. Drive the vehicle until it reaches normal
operating temperature. This may take
up to
20 mi (30 km).
2. Make sure that your vehicle is on level ground.
3. With the engine running, parking brake
engaged and your foot on the brake
pedal, move the gearshift lever through
all of the gear ranges. Allow sufficient
time for each gear to engage.
4. Make sure the parking brake is on. Make
sure the transmission is in park (P) or
neutral (N) and leave the engine
running.
5. Open the hood. See
Opening and
Closing the Hood (page 188).
6. Remove the dipstick and wipe it with a clean, lint-free cloth. See
Under
Hood Overview (page 191).
7. Replace the dipstick and remove it again to check the fluid level.
8. If the fluid level is correct, replace the dipstick and make sure it is fully seated.
Note: If the fluid level is between the
maximum and minimum marks, the fluid
level is acceptable. Do not add fluid. Transmission Fluid Level
Low Fluid Level
If the fluid level is at or below the minimum
mark, add fluid immediately. See
Capacities and Specifications
(page
261).
Note: If there is no indication of fluid on the
dipstick, have your vehicle checked
immediately.
Correct Fluid Level Make sure that the fluid level is between
the maximum and minimum marks.
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2. Remove the clips that secure the air
filter housing cover. Push the air filter
cover forward and away from you when
pulling up slightly to release it.
3. Remove the air filter element from the
air filter housing. 4. Remove and install a new foam filter
if needed according to the service
interval indicated in the scheduled
maintenance information in this guide.
If you do not replace the foam filter, be
sure the existing foam filter is in place. 5.
Install a new air filter element. Be sure
that the groove seal on the pleated
paper filter traps both sides of the
vertical partition of the air box.
6. Engage the clips to secure the air filter housing cover to the air filter housing.
Be careful not to crimp the filter
element edges between the air filter
housing and cover. Ensure that you
align the tabs on the edge properly into
the slots.
7. Reconnect the mass airflow sensor electrical connector to the inlet tube.
Make sure the locking tab on the
connector is in the locked position.
CHANGING THE ENGINE AIR
FILTER - 6.8L WARNING: To reduce the risk of
vehicle damage and personal burn
injuries, do not start your engine with the
air cleaner removed and do not remove
it while the engine is running.
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Regular fuel filter changes are an
important part of engine maintenance;
failing to keep with the scheduled
maintenance could lead to engine
performance issues and fuel injection
system damage. See Scheduled
Maintenance (page 322).
Use only recommended service parts
conforming to specifications. See
Motorcraft Parts
(page 257).
Note: Using fuel that has high levels of
impurities may require more frequent filter
replacements than the service interval
specifies.
Diesel Fuel Conditioner Module
Filter
Removal
1. Access the underside of your vehicle. 2. The diesel fuel conditioner module is
on the left-hand frame rail. 3. Drain the diesel fuel conditioner
module. Turn the drain plug
counterclockwise until it stops. Do not
use any tools to loosen the drain plug.
Drain the filter, approximately
0.5 gal
(2 L), into an appropriate container.
Do not re-use the fuel drained from the
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Never use compressed air or dry
sweeping to clean the work area. Use an
industrial vacuum cleaner with a HEPA
filter system and rags soaked in water
and wrung until nearly dry. Dispose of
used rags with care to avoid getting dust
in the air. Use an approved respirator
when emptying vacuum cleaners and
handling used rags.
Worker clean-up: Wash your hands
before eating, drinking or smoking.
Vacuum your work clothes after use and
then launder them separately, without
shaking them, to prevent fiber dust
getting into the air.
Your vehicle is equipped with
non-asbestos brake linings. However,
exposure to excessive amounts of brake
material (whether asbestos or
non-asbestos, fiberglass, mineral wool,
aramid or carbon) may be a serious health
hazard.
Air Brakes WARNING: Do not manually
adjust the automatic slack adjusters to
correct excessive push rod stroke as it
may result in reduced brake
effectiveness and a vehicle crash.
Excessive push rod stroke indicates that
a problem exists with the automatic
adjuster, with the installation of the
adjuster, or with foundation brake
components that manual adjustment
does not remedy. Seek service from a
qualified facility for excessive push rod
stroke. Inspection and Adjustment
Establish a regular schedule for periodic
cleaning, lubrication and adjustment
inspection based on vehicle use. Exact
maintenance intervals are difficult to
predetermine due to vehicle applications
and operating conditions. If you are
uncertain of the proper schedule for your
vehicle, contact an authorized dealer.
Regular inspections should include:
•
Periodic checking (every service
interval) of push rod travel or brake
adjustment. This is essential for
effective braking. Brake chamber push
rods on original equipment chambers
now incorporate an orange paint
marker near the base of the push rod
as a stroke indicator to aid in
adjustment checks. If the push rod is
clean and the brakes are out of
adjustment, you can see the orange
marker protruding from the chamber
when the brakes are applied.
• Checking the brake lining (every service
interval). When brake linings or blocks
wear within 0.063 in (1.6 mm) they
must be replaced.
• Periodic checking (every service
interval) of the air compressor filter.
Check the filter minder and when the
indicator is near or on the red line
marked
Service, replace the filter and
reset the service filter minder.
Do not back off or disconnect the front
brakes so that they are less effective,
letting the rear brakes do all the stopping
of your vehicle. Do not overlook the brakes
on the trailer either. Brake condition on the
trailer is just as important as the tractor.
Proper brake balance on trucks and
tractor-trailers is essential for effective
braking.
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Once a year, inspect the entire brake
system:
•
Rubber components for deterioration.
A qualified technician should inspect
these components and replace them
as necessary. Replacement intervals
vary according to the severity and
length of vehicle service.
• Condition of brake drums, brake
chambers and slack adjusters.
• System for air leaks.
• Hose or pipes for rust, damage and
deterioration.
• Operation of service and parking
brakes.
Periodically inspect parts such as air brake
chamber diaphragm, air compressor and
air cleaner. Replace any parts if you can
consider them unserviceable.
Air Dryer
Climactic conditions affect performance
of desiccant or after-cooler type air dryers.
You must establish a maintenance
schedule for each specific operation.
The use of an air dryer on a vehicle does
not eliminate the need to drain the air
reservoirs periodically.
Inspect for moisture in the air system by
opening reservoirs, draincocks or valves
and checking for presence of water. The
presence of small amounts of water due
to condensation is normal and is not an
indication that the dryer is not functioning
properly. Replace or rebuild the desiccant cartridge
when you determine that the desiccant is
contaminated and does not have adequate
water absorption capacity. The desiccant
change interval may vary. A general
recommendation is to replace the
desiccant every 12 months (yearly). If
experience has shown that extended or
shortened life has resulted for a particular
installation, then the yearly interval can be
increased or decreased accordingly.
Draining the Air Brake Reservoir
WARNING: Failure to drain air
brake reservoirs can result in a reduction
or loss of braking ability due to fluid
accumulation in the reservoir and/or
possible freeze-up during cold weather.
Completely drain all the air brake reservoirs
daily by opening the draincock at the ends
of the tanks. (Where accessible.
Pull-chains are used when the drains are
undercab or otherwise inaccessible.) Close
the draincock after draining. Manually drain
any air tanks equipped with automatic
moisture ejector valves, as required, to
maintain a dry air system. Contact an
authorized dealer if you are unsure of the
air reservoir locations or the draining
procedure.
Hydraulic Brakes
Establish a regular schedule for periodic
cleaning, lubrication and adjustment
inspection based on vehicle use. Exact
maintenance intervals are difficult to
predetermine due to vehicle applications
and operating conditions. If you are
uncertain of the proper schedule for your
vehicle, contact an authorized dealer.
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Regular inspections should include:
•
Checking the brake lining (every service
interval). Establish inspection intervals
that provide for lining replacement
before damage to the disc occurs.
Excessive lining wear may expose the
backing plate to the disc causing
scoring of the disc faces. A qualified
technician should perform this
inspection and keep to instructions
provided by the service manual.
Hydraulic brake systems are
power-assisted. There is a great
reduction in braking capabilities
without engine assist.
• Proper fluid level. The level should be
at the bottom edge of the ring on each
reservoir fill port. Do not fill the master
cylinder to the top of the reservoir. If
fluid level requires attention to
maintain a proper master cylinder level,
this is an indication of either severe
operation (pad wear) or fluid leakage.
A more frequent and thorough brake
inspection is required.
• Brake lines, hoses and fittings. Repair
or replace brake line tubes, hoses or
fittings as required. Inspect these
components every 4,000 mi
(6,000 km) for the following.
• Lines for kinks, dents, corrosion or
rupture.
• Hoses for abrasions, kinks, soft
spots or rupture, collapse, cracks,
twists or loose frame supports.
When replacing a hose, be sure
there is adequate clearance to the
hose to avoid an abrasion to the
new hose.
• All connections for leaks. Driveline Parking Brake WARNING:
Use wheel chocks and
exercise caution when inspecting under
the vehicle. A vehicle roll-away could
result in property damage, personal injury
or death.
A qualified technician should adjust the
parking brake and keep to the instructions
in the service manual.
AXLE INSPECTION
Front Axle
Maintaining the front axle alignment to
specifications is very important. A qualified
technician should check and maintain the
alignment.
Regular inspections should include:
• Toe-in inspection and adjustment (if
necessary), particularly with radial
tires.
• Checking for proper tightness of axle
mounting U-bolt nuts, attaching or
mounting bolts and nuts.
• Checking the axle for damage, binding,
worn parts and adequate lubrication.
• Checking the kingpins for excessive
wear. Also, perform this check during
other scheduled maintenance, for
example as tire rotation or service,
wheel bearing service and alignment.
See the workshop manual for proper
procedures.
Toe-in
It is essential to maintain correct toe-in
and tire pressure for optimum tire wear.
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SUSPENSION SYSTEM
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.
Maintain proper alignment at all times.
• U-bolts. After the chassis has been
operating under load for 1,000 mi
(1,600 km) or six months (whichever
comes first), the U-bolt nuts must be
re-torqued. Re-torque the U-bolt nuts
every
37,000 mi (60,000 km)
thereafter. Clean and lubricate the
U-bolt and nut threads and seats to
make sure a like new condition when
re-torqueing. See
Spring U-Bolt
Check (page 228).
FRAME AND TOW HOOK
INSPECTION
Your vehicle's chassis is manufactured
with frame rails of either HSLA steel or
heat-treated steel. Handle each in a
specific manner to make sure maximum
service life. Consult the service manual or
an authorized dealer before attempting
frame repair or modification. It is important, particularly on vehicles that
use tow hooks frequently, to inspect the
front and rear tow hooks for damage or a
loose mounting.
REAR AXLE FLUID CHECK
Your rear axle may have an optional
synthetic lubricant that 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. Only use a
lubricant that meets manufacturer
specifications. Use of a non-approved rear
axle lubricant may cause internal axle
component damage. See Capacities and
Specifications
(page 261).
Checking the Fluid Level
1. Park your vehicle on level ground.
2. Set the parking brake and shift into position neutral (N) or park (P). Turn
the engine off.
3. Clean any dirt from around the axle filler plug.
4. Remove the filler plug and inspect the lubricant level. It should be at 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.
Changing the Fluid
Note: Drain the rear axle while the lubricant
is warm.
1. Park your vehicle on level ground.
2. Set the parking brake and shift into position neutral (N) or park (P). Turn
the engine off.
3. Clean any dirt from around the axle filler and drain plugs.
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Specification
Name
XL-1 -
Lock cylinders (Canada):
Penetrating Fluid
CXC-51-A
-
Lock cylinders (Mexico):
Penetrating and Lock Lubricant
MXL-1
WSD-M1C227-A
Transmission, parking brake linkages and pivots, brake
pedal shift:
Motorcraft® Premium Long-Life Grease
XG-1-E1
1 See the SAE viscosities grades chart for correct temperature usage.
If you use oil and fluids that do not meet
the defined specification and viscosity
grade, this could lead to:
• Component damage that your vehicle
warranty does not cover.
• Longer engine cranking periods.
• Increased emission levels.
• Reduced engine performance.
• Reduced fuel economy.
• Reduced brake performance.
Note: We recommend an engine block
heater at temperatures below – 10°F
(– 23°C).
Engine Oil Specifications
The use of correct oil viscosities for diesel
engines is important for satisfactory
operation. Determine which oil viscosity
best suits the temperature range you
expect to encounter for the next service
interval from the following SAE viscosity
grade chart.
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