Replacing The Tires - Mercury 1999 Mountaineer Owner's Manual

Four 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 tire
pressure decal. Make sure that all tires are the same size, speed rating,
and load-carrying capacity. Use only the tire combinations
recommended on the decal. 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
211