FORD 2003 Expedition v.4 - Manual (Page 318)

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 3 hours or has been driven less than 5 km (3
miles). As you drive, the temperature in the tire warms up, increasing
the tire pressure.
• 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.
• Check tires for proper air pressure monthly. Check spare tire for
proper air pressure every six months.
Check that the externally mounted spare tire is tight. Refer to Stowing
the flat/spare tire of the tire changing section in the Roadside
Emergencies chapter
Improperly inflated tires can affect vehicle handling and can fail
suddenly, possibly resulting in loss of vehicle control, vehicle
rollover and/or personal injury.
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.
Maintenance and Specifications
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