Owner Checks and Services

Certain basic maintenance checks and inspections should be performed by the owner or a service technician at the intervals indicated. Service information and supporting specifications are provided in this owner’s guide.
Any adverse condition should be brought to the attention of your dealer or qualified service technician as soon as possible for the proper service advice. The owner maintenance service checks are generally not covered by warranties so you may be charged for labor, parts or fluids used.

See also:
All-wheel drive (if equipped)
Your vehicle may be equipped with a full-time all-wheel drive (AWD)
system. The AWD system is an active system, meaning it not only
responds to wheel slip between the front and rear axles but also ...
Second generation (2003–2006)
The Navigator was updated in 2003, along with the Ford Expedition, on the new
Ford U platform. The interior was also substantially revised to bring it up to
the level expected by luxury buyers. So ...
Tires
Tires are designed to give many thousands of miles of service, but they
must be maintained in order to get the maximum benefit from them. ...
