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
229
2012 F-650/750(f67)
Supplement, 2nd Printing
USA(fus)
