Ford F-150 2000 Introduction Manual page 225

Five tire rotation
Replacing the tires
Replace the tires when the wear
band is visible through the tire
treads.
When replacing full size tires, never mix radial bias-belted, or
bias-type tires. Use only the tire sizes that are listed on the
Certification Label. Make sure that all tires are the same size, speed
rating, and load-carrying capacity. Use only the tire combinations
recommended on the label. If you do not follow these precautions,
your vehicle may not drive properly and safely.
Make sure that all replacement tires are of the same size, type,
load-carrying capacity and tread design (e.g., "All Terrain", etc.),
as originally offered by Ford.
Maintenance and care
225