Treadwear

The treadwear grade is a comparative rating based on the wear rate of the tire when tested under controlled conditions on a specified government test course. For example, a tire graded 150 would wear one and one-half (11⁄2) times as well on the government course as a tire graded 100. The relative performance of tires depends upon the actual conditions of their use, however, and may depart significantly from the norm due to variations in driving habits, service practices, and differences in road characteristics and climate.
See also:
Vehicle storage
If you plan on storing your vehicle for an extended period of time
(30 days or more), refer to the following maintenance recommendations
to ensure your vehicle stays in good operating condition.
...
Underbody
Flush the complete underside of your vehicle frequently. Keep body and
door drain holes free from packed dirt. ...
All-wheel drive (AWD) system (if equipped)
Your vehicle may be equipped with a full-time all-wheel drive (AWD)
system. With the AWD option, power will be delivered to the front
wheels and distributed to the rear wheels as needed. This incr ...
