Ford Mercury Villager 1997 Owner's Manual page 306

A worn-out tire
Because your vehicle's tires may wear unevenly, you may need
to replace them before a wear band appears across the entire tread.
Your wheels and tires are match-mounted for improved ride.
Before you begin to repair a tire, mark the wheel and tire so that
they are properly aligned when remounted. This will ensure
that the tires will continue to give you the same ride level.
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.
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