FORD 2002 F-550 v.1 - Manual (Page 283)

The temperature grade for this tire is established for a tire that
is properly inflated and not overloaded. Excessive speed,
underinflation, or excessive loading, either separately or in
combination, can cause heat buildup and possible tire failure.
SERVICING YOUR TIRES
Checking the tire pressure
• Use an accurate tire pressure gauge.
• Check the tire pressure when tires are cold, after the vehicle has been
parked for at least one hour or has been driven less than 5 km
(3 miles).
• Adjust tire pressure to recommended specifications found on the
Certification Label. Tire pressure information can also be found on the
Tire Information label located on the inside of the fuel filler door.
Improperly inflated tires can affect vehicle handling and can fail
suddenly, possibly resulting in loss of vehicle control.
Maintenance and specifications
283