8.
U.S. DOT Tire Identification Number (TIN):
This begins with the
letters “DOT” and indicates that the tire meets all federal standards. The
next two numbers or letters are the plant code designating where it was
manufactured, the next two are the tire size code and the last four
numbers represent the week and year the tire was built. For example,
the numbers 317 mean the 31st week of 1997. After 2000 the numbers
go to four digits. For example, 2501 means the 25th week of 2001. The
numbers in between are identification codes used for traceability. This
information is used to contact customers if a tire defect requires a recall.
9.
M+S or M/S:
Mud and Snow, or
AT:
All Terrain, or
AS:
All Season.
10.
Tire Ply Composition and Material Used:
Indicates the number of
plies or the number of layers of rubber-coated fabric in the tire tread and
sidewall. Tire manufacturers also must indicate the ply materials in the
tire and the sidewall, which include steel, nylon, polyester, and others.
11.
Maximum Load:
Indicates the maximum load in kilograms and
pounds that can be carried by the tire. Refer to the Safety Compliance
Certification Label, which is located on the B-Pillar or the edge of the
driver’s door, for the correct tire pressure for your vehicle.
12.
Treadwear, Traction and Temperature Grades
•
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 (1
1
⁄
2
) times as well on the government
course as a tire graded 100.
•
Traction:
The traction grades, from highest to lowest are AA, A, B,
and C. The grades represent the tire’s ability to stop on wet pavement
as measured under controlled conditions on specified government test
surfaces of asphalt and concrete. A tire marked C may have poor
traction performance.
•
Temperature:
The temperature grades are A (the highest), B and C,
representing the tire’s resistance to the generation of heat and its
ability to dissipate heat when tested under controlled conditions on a
specified indoor laboratory test wheel.
Tires, Wheels and Loading
229
2010 Navigator
(nav)
Owners Guide
(own2002)
, 1st Printing
USA
(fus)
