Damage
Periodically inspect the tire treads and sidewalls for damage (such as bulges in the tread or sidewalls, cracks in the tread groove and separation in the tread or sidewall). If damage is observed or suspected have the tire inspected by a tire professional. Tires can be damaged during off-road use, so inspection after off-road use is also recommended.
WARNING: Age
Tires degrade over time depending on many factors such as
weather, storage conditions, and conditions of use (load, speed,
inflation pressure, etc.) the tires experience throughout their lives.
In general, tires should be replaced after six years regardless of tread wear. However, heat caused by hot climates or frequent high loading conditions can accelerate the aging process and may require tires to be replaced more frequently.
You should replace your spare tire when you replace the road tires or after six years due to aging even if it has not been used.
See also:
Reaking-in your vehicle
Your vehicle does not need an extensive break-in. Try not to drive
continuously at the same speed for the first 1,000 miles (1,600 km) of
new vehicle operation. Vary your speed frequently in order ...
Running out of fuel
If you have run out of fuel and need to refill the vehicle with a portable
fuel container, see Running out of fuel in the Maintenance and
Specifications chapter for proper fuel filling method usin ...
Overview
The Lincoln Navigator serves as Lincoln's full-sized luxury SUV. The
Navigator shares the same platform with the lesser Ford Expedition full-size
SUV. Introduced in 1998, the Navigator has proven ...