FORD 2003 F-550 v.4 - Manual (Page 250)

Tire inflation information
All tires with Steel Carcass Plies (if equipped):
This type of tire utilizes steel cords in the sidewalls. As such, they
cannot be treated like normal light truck tires. Tire service, including
adjusting tire pressure, must be performed by personnel trained,
supervised and equipped according to Federal Occupational Safety and
Health Administration (OSHA) regulations. For example, during any
procedure involving tire inflation, the technician or individual must
utilize a remote inflation device, and insure that all persons are clear of
the trajectory area.
WARNING An inflated tire and rim can be very dangerous if
improperly used, serviced or maintained. To avoid serious injury,
never attempt to re-inflate a tire which has been run flat or seriously
under-inflated without first removing the tire from the wheel assembly
for inspection. Do not attempt to add air to tires or replace tires or
wheels without first taking precautions to protect persons and
property.
Tire rotation
Because your vehicle’s tires perform different jobs, they often wear
differently. To make sure your tires wear evenly and last longer, rotate
them as indicated in the scheduled maintenance guide. If you notice that
the tires wear unevenly, have them checked.
The following procedure applies to vehicles equipped with single rear
wheel.
2003 F250/350/450/550 (f23)
Owners Guide (post-2002-fmt)
USA English (fus)
Maintenance and Specifications
250