wheel size AUDI E-TRON 2019 User Guide
Page 262 of 310
Wheels 
  
Uniform tire quality grading 
— Tread wear 
— Traction AAABC 
— Temperature ABC 
Quality grades can be found where applicable on 
the tire side wall between tread shoulder and 
maximum section width > page 244, fig. 162. 
For example: Tread wear 200, Traction AA, Tem- 
perature A. 
All passenger car tires must conform to Federal 
Safety Requirements in addition to these grades. 
Tread wear 
The tread wear grade is a comparative rating 
based on the wear rate of the tire when tested 
under controlled conditions on a specified gov- 
ernment test course. 
For example, a tire graded 150 would wear one 
and one half (1 1/2) times as well on the govern- 
ment 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. 
Traction 
The traction grades, from highest to lowest, are 
AA, A, B and C. Those grades represent the tire's 
ability to stop on wet pavement as measured un- 
der controlled conditions on specified govern- 
ment test surfaces of asphalt and concrete. A tire 
marked C may have poor traction performance 
>A. 
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. 
Sustained high temperature can cause the mate- 
rial of the tire to degenerate and reduce tire life, 
and excessive temperature can lead to sudden 
tire failure > A. 
260 
The grade C corresponds to a  Level of perform- 
ance which all passenger car tires must meet un- 
der  the Federal Motor Vehicle Safety Standard 
No. 109. Grades B and A represent higher levels 
of performance on the laboratory test wheel than 
the minimum required by law. 
  
Z\ WARNING 
The traction grade assigned to this tire is 
based on straight-ahead braking traction 
tests, and does not include acceleration, cor- 
nering, hydroplaning or peak traction charac- 
teristics. 
  
  
ZA\ WARNING 
The temperature grade for this tire is estab- 
lished for a tire that is properly inflated and 
not overloaded. Excessive speed, underinfla- 
tion, or excessive loading, either separately or 
in combination, can cause heat buildup and 
possible tire failure. 
     
ZA WARNING 
Temperature grades apply to tires that are 
properly inflated and not over or underinflat- 
ed. 
      
Tire pressure monitoring 
system 
(1) General notes 
Each tire, including the spare (if provided), 
should be checked monthly when cold and inflat- 
ed to the inflation pressure recommended by the 
vehicle manufacturer on the vehicle placard or 
tire inflation pressure label. (If your vehicle has 
tires of a different size than the size indicated on 
the vehicle placard or tire inflation pressure la- 
bel, you should determine the proper tire infla- 
tion pressure for those tires). 
As an added safety feature, your vehicle has been 
equipped with a tire pressure monitoring system 
(TPMS) that illuminates a low tire pressure tell- 
tale when one or more of your tires is significant- 
ly under-inflated. Accordingly, when the low tire 
pressure telltale illuminates, you should stop and >