Replacing The Tires - Mercury 2000 Grand Marquis Owner's Manual

Maintenance and care
Five tire rotation (for vehicles
with steel wheels and full size
spare tires)

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.
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