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:
Satellite Radio
Satellite radio is available only with a valid SIRIUS radio
subscription. Check with your authorized dealer for availability.
SIRIUS: Press repeatedly to access satellite radio mode, if equipped.
...
Underbody
Flush the complete underside of your vehicle frequently. Keep body and
door drain holes free from packed dirt. ...
Vertical aim adjustment
1. Park the vehicle directly in front of a wall or screen on a level surface,
approximately 25 feet (7.6 meters) away.
• (1) 8 feet (2.4 meters)
• (2) Center height of lamp to ground
• (3) 25 ...
