FORD 2002 F-150 v.1 - Manual (Page 196)

Each day before you drive, check
your tires. If one looks lower than
the others, use a tire gauge to check
pressure of all tires, and adjust if
required. Check tire pressure with a
tire gauge every few weeks
(including spare). Safe operation
requires tires that are neither
underinflated nor overloaded.
Periodically inspect the tire treads and remove stones, nails, glass or
other objects that may be wedged in the tread grooves. Check for holes
or cuts that may permit air leakage from the tire and make necessary
repairs.
Inspect the tire side walls for cuts, bruises and other damage. If internal
damage to the tire is suspected, have the tire demounted and inspected
in case it needs to be repaired or replaced.
Maintenance and Modifications
The suspension and steering systems on your vehicle have been designed
and tested to provide both reasonably safe, predictable performance
whether loaded or empty and durable load carrying capability. For this
reason, Ford strongly recommends that you do not make modifications
such as adding or removing parts (such as lift kits or stabilizer bars) or
by using replacement parts not equivalent to the original factory
equipment.
Any modifications to a vehicle that raise the center of gravity can make
it more likely the vehicle will roll over as a result of a loss of control.
Ford recommends that caution be used with any vehicle equipped with a
high load or device (such as ladder racks or pickup box cover).
Failure to maintain your vehicle properly may void the warranty, increase
your repair cost, reduce vehicle performance and operational capabilities
and adversely affect driver and passenger safety. Frequent inspection of
vehicle chassis components is recommended if the vehicle is subjected to
heavy off-road usage.
Driving
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