2012 FORD F650 suspension

FIFTH-WHEEL OPERATION
WARNING:Failure to follow the fifth-wheel manufacturer’s
instructions for hooking and unhooking as well as sliding the
fifth-wheel could result in an accident, personal injury or death.
WARNING:When the tractor and trailer are parked unattended,
the trailer brake hand control should never be used to apply the
brake, since air may leak from the system, allowing vehicle movement,
resulting in possible property damage, personal injury or death.
Before hook-up, make sure:
•The fifth-wheel jaws are fully opened.
•The fifth-wheel is fully tilted back to prevent body damage when the
tractor is backed under a trailer.
•The trailer wheels are blocked and the trailer spring brakes are
adjusted and applied. Never chase a trailer.
•The brake hoses and light cords are clear of the fifth-wheel.
Hook-up
1. Back the tractor squarely under the trailer, engaging the fifth-wheel
jaws on the kingpin. Always back-up slowly, making sure the trailer is
neither too high nor too low. Avoid backing under the trailer from an
angle.
2. Connect the service and emergency brake hoses and trailer light
connector. Refer toTractor-trailer connectionsin theAir suspension
section of this chapter, adhering to the warning and using the three-point
stance while connecting and disconnecting the trailer.
3. Inspect the jaws of the fifth-wheel to be sure they have fully closed on
the trailer kingpin and the trailer plate is resting securely on the
fifth-wheel.
4. Be sure the coupler release lever is in the locked position.
5. Charge the trailer brake system. Set the trailer brakes, either with the
hand valve or tractor protection valve. Pull against the trailer for an
additional check of proper hook-up. Do not pull hard enough to damage
or strain the equipment.
Driving
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Fuse/Relay
locationFuse amp
ratingFuse description
15 10A Interior lamp relay
16 15A High beams, Indicator
17 — Not used
18 5A Dimmer switch, Interior lighting
19 15A Engine control (diesel engine only)
20 5A Starting system
21 10A DRL resistor
22 15A Air horn, Air suspension dump, Two-speed
axle, Driver-controlled locking differential
23 10A Flasher relay
24 15A Hydraulic brakes relay, Fuel heater relay
(diesel engine only), Air dryer
25 10A Blower motor relay coil
26 10A Right-hand low beam headlight
27 — Not used
28 10A Left-hand low beam headlight
29 10A Cluster, GEM
30 15A Allison electronic transmission
31 15A Mirror fold relay
Relay 1 — Interior lamps
Relay 2 — Not used
Relay 3 — Horn
Relay 4 — Not used
Relay 5 — Not used
Roadside Emergencies
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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.
Maintenance and Specifications
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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.
Maintenance and Specifications
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If rib tire is used on front axle and lug or off-road type on rear axle
positions:
1.Front (Steering) Axle:Replace tires at front wheels when tread is
worn to 4/32 inch (3 mm) or less.
2.Rear Axles:Tires must be removed when the tread is worn to
2/32 inch (2 mm) or less. Tires identified with the word “re-groovable”
molded on the sidewall can be re-grooved. A minimum of 3/32 inch
(2.5 mm) of under-tread must be left at the bottom of the grooves.
Wheel and tire balancing
Out-of-round or out-of-balance wheels or tires can cause vehicle
vibration, bounce and shimmy. Replace damaged or out-of-round wheels.
Out-of-round tires and wheel assemblies can be corrected by re-clocking
the tire relative to the wheel.
The tire and wheel assembly should then be dynamically balanced.
Wear
Radial tires can exhibit three types of normal wear patterns:
1. Even
2. Erosion
3. Chamfer
Even wearis a sign that the tire is being properly used and maintained.
Erosion wearhas also been called rolling wear, channel or river wear.
Erosion wear is found more often at free rolling tires. This is an
indication that the tire is being used in a slow wearing operation. What
happens is that the belt plies are held very rigid and the tread is not
allowed to distort as it passes through the contact area. Wear only occurs
at the edge of the tread. No corrective action required. If erosion gets to
be 1/16 inch (2 mm) or more, the tire may be rotated to a drive axle.
Chamfer or shoulder wear,with tires inflated properly, is a normal
tendency of most radial tire designs. If both inside and outside shoulders
are wearing evenly around the tire, no further action is required.
Over-inflation is not effective in correcting this effect.
Tires: Irregular Wear
If irregular wear is present, check the axle alignment, tire pressure,
wheel balancing, shock and suspension component condition, and wheel
bearing end play.
This condition not only shortens tire life, but adversely affects the
handling of your vehicle, which is dangerous.
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Rotating tires from one wheel position to another is a way often used to
even out many types of irregular wear or to avoid it altogether. Some of
the more effective tire rotation programs are:
•Steer tires that have developed some type of irregular wear pattern
can be rotated to drive axles if rib tires are being used on all wheel
positions. Applying steer tires to a drive position often cleans them
and they can be moved back to the steer axles or run out to re-tread
stage on the rear axle.
•Another rotation possibility for fleets with rib tires in all wheel
positions is to break in the new steer tires in the drive axle positions,
then move them to steer axles. This wears away tread rubber
relatively quickly in the early life of a tire when it is most likely to
develop an unusual wear pattern.
•Drive axle tires may be placed on the other end of the same axle so
that direction of rotation is reversed. This is often helpful if a heel and
toe or alternate lug wear pattern has developed.
Irregular wear can be minimized by:
•Using the right inflation pressure for the load being carried.
•Maintaining proper front wheel alignment -especially toe-in-to
specifications.
•Maintaining proper tire and wheel balance.
•Maintaining shock absorbers and suspension components.
Use of tire chains
Refer to chain manufacturer’s recommendation for correct tire chain
usage, installation and removal.
Maintenance and Specifications
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Daily owner checks
U.S. Department
of Transportation,
Federal Highway
Administration
requirements
(ensure that the
entire system is
functioning
properly)Service brakes
Parking brake
Steering mechanism
Lighting devices and reflectors
Tires
Horn
Windshield wipers
Rear vision mirrors
Wheels and rims
Emergency equipment
Every oil change
EngineInspect engine cooling system hoses, clamps and
protection.*
Inspect drive belts.
Exhaust systemInspect entire exhaust system (including the inlet
pipe(s), muffler(s), outlet pipe(s), clamps and
fasteners) for holes, leakage, breakage, corrosive
damage and separation from other components.
Adjust, service or replace with the same or the
equivalent part. (Also a noise emission control
service.)
SuspensionTighten the front and rear spring U-bolts to the
specified torque.
Driveline and rear
axleLubricate the U-joints and the slip yoke.
Scheduled Maintenance Guide
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