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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
module. 4. Disconnect the electrical connector.
5. Fully loosen the bolts securing the
lower portion of the diesel fuel
conditioner module housing.
Note: Do not fully remove the bolts from
the lower portion of the diesel fuel
conditioner module housing.
6. Remove the lower portion of the diesel
fuel conditioner module housing.
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5
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7. Slide the filter element toward the
drain plug to disengage the securing
clips.
Installation
1. Slide the filter element into the housing
and fully engage the securing clips.
2. Install the lower portion of the housing.
Tighten the bolts until you feel a strong
resistance. Maximum torque 7 lb.ft
(9 Nm).
3. Connect the electrical connector.
4. Tighten the drain plug, turn it clockwise
until it stops and you feel a strong
resistance. Do not use any tools to
tighten the drain plug.
5. Switch the ignition on for 30 seconds and then switch the ignition off. Repeat
this operation six times in a row to
purge any trapped air from the fuel
system. Engine-mounted Fuel Filter
Although the fuel system is not fully
pressurized when the vehicle is off, some
residual pressure may remain in the fuel
system since it can take some time for the
pressure to completely bleed off.
Therefore, we recommend you place an
absorbent cloth below the filter connectors
to absorb any fuel that may drain.
The engine-mounted fuel filter is a plastic
disposable cartridge.
Removal
1.
Disconnect the fuel lines by squeezing
the connector tabs and pulling the lines
straight off.
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•
Maintaining proper steering gear and
power steering pump lubricant levels.
• Checking steering column joint bolts
and steering linkage, particularly for
body-to-chassis clearance.
Steering Column Joint Bolts
As a good maintenance practice, check
steering column joint bolt tightness every
60,000 mi (96,000 km) or annually,
whichever occurs first. Do not overtighten
the bolts.
Hydraulic System
Whenever draining and refilling the power
steering's hydraulic system for any reason,
bleed air from the system before returning
the vehicle to service. Failure to bleed the
hydraulic system properly can result in
degradation of power system performance.
Consult an authorized dealer who is aware
of the proper procedures for filling and
bleeding the system.
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 224).
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 258).
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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.
4. Remove the filler and drain plugs. Drain
the lubricant into a suitable container.
Dispose of all used automotive fluids
in a responsible manner following your
local authorized standards.
5. Clean and install the drain plug securely.
6. Add lubricant through the filler plug opening.
7. Clean and install the filler plug securely.
SPRING U-BOLT CHECK
Check and tighten the U-bolt nuts after
your vehicle has been operated under load
for 1,000 mi (1,600 km) or six months,
whichever occurs first. Thereafter, install new U-bolt nuts and
washers every
36,000 mi (58,000 km).
Check and tighten the U-bolt nuts with
your vehicle at curb height and unloaded.
Inspect the U-bolt threads for rust and
debris. Clean the threads if contaminated.
U-bolt Nut Torque
Front Axle
Note: Check and tighten the U-bolt nuts
evenly using a criss-cross pattern in the
following stages. lb.ft (Nm)
Stage
40 (60)
1.
90 (125)
2.
170 (225)
3.
240 (325)
4.
Rear Axle
Note: Check and tighten the U-bolt nuts
evenly using a criss-cross pattern in the
following stages. lb.ft (Nm)
Stage
60 (75)
1.
90 (125)
2.
170 (225)
3.
240 (325)
4.
320 (440)
5.
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