Uniform Tire Quality Grading
The following information relates to the tire
grading system developed by the National
Highway Traffic Safety Administration
(NHTSA), which grades tires by tread wear,
traction and temperature performance. Tires
that have deep tread, and winter tires, are
exempt from these marking requirements.
Where applicable, quality grades are found on
the tire’s sidewall between the tread shoulder and maximum section width. For example:
• TREADWEAR 180
• TRACTION AA
• TEMPERATURE A
The quality grades are descibed next.
Note: In addition to the marking requirements,
passenger car tires must conform to Federal
Safety Requirements.
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 wears one and
a half times better on a government test course than a tire graded 100. The relative
performance of tires depends on the actual
conditions of their use, however, and can depart significantly from the norm due to
variations in driving habits, service practices, road characteristics, and climate.
Traction
The traction grades, from highest to lowest,
are: AA, A, B, and C. These grades represent a
tire’s ability to stop on wet pavement as
measured under controlled conditions on test
surfaces of asphalt and concrete. A tire
marked C might have poor traction performance.Warning: Defective tires are dangerous.
Do not drive if a tire is damaged,
excessively worn, or is inflated to an
incorrect pressure. The safety of the
vehicle and occupants can be adversely
affected. Check tires regularly for wear
and to ensure there are no cuts, bulges or
exposure of the ply/cord structure.Warning: The traction grade assigned to
the tire is based on straight-ahead
braking tests, and doesn’t include:acceleration, cornering, hydroplaning or
peak traction characteristics.
Temperature
The temperature grades are A (the highest), B, and C, representing the tire’s resistance tothe generation of heat and its ability to
dissipate heat when tested under controlled
conditions on a specified indoor laboratory test wheel. Sustained high temperature cancause the tire to degenerate and reduce tirelife, and excessive temperature can lead to
sudden tire failure.
The grade C corresponds to the minimum
level of performance that all passenger car
tires must meet under the Federal Motor Safety Standard No. 109. Grades B and A
represent levels of performance on the
laboratory test wheel that exceed the
minimum requirements.
Warning: A tire’s temperature grade is
established for a tire that is properly
inflated and not overloaded. Excessive
speed, under-inflation, or excessive
loading, either separately or in
combination, can cause heat buildup and
possible tire failure.
Wheels and Tires
Specifications139
Tesla Roadside Assistance is available to you, 24 hours a day, 365 days a year, for the duration of
your warranty period.
To contact Roadside Assistance, call:
1-877-79TESLA (1-877-798-3752)
Advise the representative of the vehicle identification number (VIN), license plate number, mileage, your location, and the nature of the problem. The VIN is on the upper dashboard on thedriver’s side of your vehicle and is visible through the windshield.
Roadside Assistance covers transportation of Model S for up to 50 miles (80 kms) in the event of
a flat tire. However, owners are responsible for transportation expenses if the Battery is over- discharged. For a complete description of the terms and conditions of the Tesla RoadsideAssistance Program, refer to the policy that was provided to you by Tesla when you purchasedModel S.
It is your responsibility to provide vehicle transporters with instructions on how to transport
Model S (see Instructions for Transporters on page 142).
Contacting Roadside Assistance
Roadside Assistance141
Copyrights and Trademarks
All information in this document and all
Model S ®
software is subject to copyright and
other intellectual property rights of Tesla
Motors, Inc. and its licensors. This material may not be modified, reproduced or copied, in
whole or in part, without the prior written permission of Tesla Motors, Inc. and its
licensors. Additional information is available upon request. The following are trademarks orregistered trademarks of Tesla Motors, Inc. in
the United States and other countries:
All other trademarks contained in this
document are the property of their respective owners and their use herein does not implysponsorship or endorsement of their products
or services. The unauthorized use of any
trademark displayed in this document or on the vehicle is strictly prohibited.
About this Owner Information
146Model S Owner's Manual
