AUDI S3 2010 Owners Manual

________________________________________________ T_ ir_e _s_ a_n_ d_ w_ h _e_e_ l_s __ lJlll
•
& WARNING
• Incorrect tire pressures and/or underinflation can lead to a
serious or fatal accident.
• Incorrect tire pressures and/or underinflation cause increased
tire wear and can affect the handling of the vehicle.
• Incorrect tire pressures and/or underinflation can also lead to
sudden tire failure, including a blowout and sudden deflation,
causing loss of vehicle control. •
Checking tire pressure
The correct tire pressure for the tires originally installed
on your vehicle is listed on the tire pressure label located
either on driver's side 8-pillar or inside the fuel filler flap.
The recommended tire pressures are on the tire pressure label and
in the table=> page
246, "Cold tire inflation pressure ". This means
that the pressure must be checked and adjusted when the tire has
not been driven for more than a couple of miles (kilometers) at low
speeds during the previous three hours. Air in the tires expands
when the tire heats up as a result of internal friction as it flexes in
use. The tire pressure is higher when the tire has warmed up than
when it is "cold."
It is the inflation pressure in a "cold" tire that counts. Therefore, you
should never let air out of a warm tire to match "Cold tire inflation
pressure" recommendations=>
page 246. The tires would then be
underinflated and could fail suddenly.
The tire pressure label on your Audi lists the recommended cold tire
inflation pressures for the new, original equipment tires that were
on your vehicle at the time it was manufactured. For the location of
the label =>
page 246, fig. 173.
Most tires lose air naturally over time. They can also lose some air if
you drive over a pothole or hit a curb while parking. It is usually not possible to see whether the radial tires used today are underinflated
just by looking at them.
Therefore, be sure to check tire pressures at least once a month and
always before going on a long trip. Make sure to take the number of
people and the amount of luggage into account when adjusting tire
pressure for a trip -even one that you would not consider to be
"long." See=>
page 250, "Tires and vehicle load limits" for more
important information .
Always use an accurate tire pressure gauge when checking and adjusting inflation pressures . Check all of the tires and be sure not
to forget the spare tire. If the pressure in any tire is too high when
the tire is "cold," let air out of the tire slowly with the edge of the tire
gauge and keep checking the pressure until you reach the pressure
that is correct for the load (passengers and luggage) and kind of
driving you plan to do .
If the pressure in any tire is too low, note the difference between the
pressure in the cold tire and the pressure you need and add the air
that you need to reach the correct pressure for the vehicle load
(passengers and luggage) for the tires on your vehicle as listed on
the on your vehicle and in this manual and the kind of driving you
plan to do.
Never exceed the maximum inflation pressure listed on the tire
sidewall for any reason.
Remember that the vehicle manufacturer, not the tire manufacturer ,
determines the correct tire pressure for the tires on your vehicle.
It is important to check the tire pressure when the tires are cold.
• Read the required tire pressure from the tire pressure label. On
USA vehicles, the tire pressure label is located on driver's side B ­
pillar. On Canada vehicles, the tire pressure label is located either on
the driver's side B -pillar or inside the fuel filler flap.
• Turn the valve stem cap counter-clockwise to remove it from the
tire valve.
• Place the air pressure gauge on the valve. ..,.
Vehicle care I t •

-~_T_ ir_e_ s_ a_ n_d _ w_ h_ e_e _l_s _________________________________________________ _
• The tire pressures should only be checked and adjusted when
t he tires are cold . The s lig htly raised pressures of warm tires must
not be reduced .
• Adjust the ti re pressure to t he loa d you are carrying.
• Reinstal l the valve stem cap on the valve.
When should I c heck the tire pressure?
The correct ti re p re ssure is especially impo rtant at h ig h speeds . The
pressure should the re fore be checked a t le ast once a month and
a lways before starting a journey. Do not forget to check the tire pres ­
sure for the spare whee l
::::> page 269.
When should
I adjust the tire pressure s?
Adjust the tire pressure to the load you are carrying. A fter chang ing
a wheel
or r eplac ing whee ls you have to adjus t th e tire pre ssures on
a ll whee ls. In addit io n, you must the n initia lize the new t ire pres ­
sures in the tire pressure monitoring system* =>
page 263.
& WARNING
Incorrect tire pressures and/or underinflation can lead sudden tire
failure, los s of control, colli sion , serious personal injury or even
death .
• When the warning symbol appears in the instrument
c luster , stop and inspect the tire s.
• Incorrect tire pressure and /or underinflation can cause
increased tire wear and can affect the handling of the vehicle and
stopping ability .
• Incorrect tire pressures and /or underinfla tion can also lead to
sudden tire failure , including a blowout and sudden deflation ,
causing loss of vehicle control .
• The driver is responsible for the correct tire pressures for all
tires on the vehicle. The applicable pre ssure values are located on
a sticke r on the driver 's side B -pillar o r on the inside of the fuel
filler flap.
& WARNING (continued )
• Only when all tires on the vehicle are filled to the correct pre s­
sure , the tire pres sure monitoring sy stem * can work correctly.
• The use of incorrect tire pressure values can lead to accidents
or other damage . Therefore it is e ssential that the driver observe
the specified tire pressure v alue s for the tires and the correct pres­
sures for the function of the tire pre ssure monitoring system* .
• Always inflate tires to the recommended and correct tire pres ­
s ure before driving off.
• Driving with underinflated tires bend more , letting them get
too hot re sulting in tread separation , sudden tire fa ilure and loss
of control.
• Excessive speed and /overloading can cause heat build -up ,
sudden tire failure and loss of control.
• If the tire pressure is too low or too high, the tires will wear
prematurely and the vehicle will not handle well.
• If the tire is not flat and you do not have to change a wheel
immediately , drive at reduced speed to the nearest service station
to che ck the tire pressure and add air as required .
0 Note
Driving without valve stem caps can cause damage to the tire
va lves. To prevent this, always make sure that fac tory ins talled va lve
stem caps on all whee ls are securely mounted on the valve.
Underinflated tires wi ll also increase the fuel consumption. •
Tires and vehicle load limits
There are limits to the amount of load or weight that any vehic le and
any tire ca n carry. A vehicle that is ove rlo aded wil l n ot h andle wel l ...

Tires and wheels -
----------------
•
and is more difficult to stop. Overloading can not only lead to loss
of ve hicle control, but can a lso damage important parts of the
vehicle and can lead to sudden tire failure, inc luding a blowout and
sudden deflation that can cause the vehic le to crash.
Your safety and that of your passengers also depends on making
sure that load limits are not exceeded. Vehicle load includes every ­
body and everything in and on the veh icle . These load limits are
technically referred to as the vehicle's
Gross Vehicle Weight Rating
("GVWR"l.
The "GVWR" includes the weight of the basic vehicle, al l factory
insta lled accessories, a full tank of fuel, oil, coolant and other fluids
plus maximum load. The maximum load includes the number of
passengers that the vehicle is intended to carry ("seating capacity")
with an assumed weight of 150 lbs (68 kg) for each passenger at a
designated seating position and the total weight of any luggage in
the vehicle. If you tow a trailer, the weight of the trailer hitch and the
tongue weight of the loaded trai ler must be included as part of the
vehicle load .
The
Gross Axle Weight Rating ("GAWR") is the maximum load that
can be applied at each of the vehic le's two axles .
The Gross Vehicle Weight Rating and the Gross Axle Weight Rating
are listed on the safety compliance sticker label located either on
the driver's side B-pillar or on the inside of the fuel filler flap. Your
Audi has 5 seating positions, 2 in the front and 3 in the rear for total
seating capacity of 5. Each seating position has a safety belt
=> page 135, "Safety belts".
The fact that there is an upper limit to your vehicle's Gross Vehicle
Weight Rating means that the total weight of whatever is being
carried in the vehicle (including the weight of a trailer hitch and the
tongue weight of the loaded trailer) is limited. The more passengers
in the vehicle or passengers who are heavier than the standard
weights assumed mean that less weight can be carried as luggage .
T he tire pressure label on your Audi also lists the maximum
combined weight of all of the occupants and luggage or other cargo that the vehicle can carry.
For the location of the label
=> page 246,
fig. 173.
& WARNING
Overloading a vehicle can cause loss of vehicle control, a crash or
other accident, serious personal injury , and even death .
• Carrying more weight than your vehicle was designed to carry
will prevent the vehicle from handling properly and increase the
risk of the loss of vehicle control.
• The brakes on a vehicle that has been overloaded may not be
able to stop the vehicle within a safe distance.
• Tires on a vehicle that has been overloaded can fail suddenly,
including a blowout and sudden deflation, causing loss of control
and a crash.
• Always make sure that the total load being transported -
including the weight of a trailer hitch and the tongue weight of a
loaded trailer -does not make the vehicle heavier than the
vehicle's Gross Vehicle Weight Rating .•
Determining correct load limit
Use the example below to calculate the
total weight of the passengers and
luggage or other things that you plan to
transport so that you can make sure that
your vehicle will not be overloaded.
~
Vehicle care I t •

-Tires and wheels
Steps for Determining Correct
Load Limit
1. Locate the statement "THE COMBINED
WEIGHT OF OCCUPANTS AND CARGO
SHOULD NEVER EXCEED XXX KG OR XXX LBS"on your vehicle's placard (tire infla­
tion pressure label)~ page 246, fig. 173.
2. Determine the combined weight of the driver and passengers that will be riding
in your vehicle.
3. Subtract the combined weight of the driver and passengers from "XXX" kilo­
grams or "XXX" pounds shown on the
sticker ~ page 246, fig. 173.
4. The resulting figure equals the available amount of cargo and luggage load
capacity. For example, if the
"XXX"
amount equals 1400 lbs. and there will
be five 150 lbs. passengers in your
vehicle, the amount of available cargo and luggage load capacity is 650 lbs. (1400-750 (5
X 150) = 650 lbs.) 5. Determine the combined weight of
luggage and cargo being loaded on the
vehicle. That weight may not safely exceed the available cargo and luggage load capacity calculated in Step 4.
6. If your vehicle will be towing a trailer, load from your trailer will be transferred
to your vehicle. Consult this manual to
determine how this reduces the avail­
able cargo and luggage load capacity of
your vehicle.
- Check the tire sidewall (~ page 254,
fig. 177) to determine the designated load rating for a specific tire. •

Tires and wheels -_______________ _____.
Tire service life
The service life of tires depends on a lot of different things
including proper installation and balancing, correct tire
pressure and driving style.
(r
\'"-----JJ
Tread Wear Indicator (TWI)
Fig . 175 Tire tread:
tread wear indicators
(TWI)
Fig . 176 Rotating tires
for more even wear
The original tires on your vehicle have 1/16 inch (1.6 mm) high "wear
indicators":::::, fig. 175 running across the tread. Depending on the
make, there will be six to eight of them evenly placed around the
tire. Marks on the tire sidewall (for example "TWI" or other symbols)
indicate the positions of the tread wear indicators. Worn tires must
be replaced. Different figures may apply in other countries.:::::,&.
Tire pressure
Incorrect tire pressure causes premature wear and can cause
sudden tire blow-out. For this reason, tire pressure must be checked
at least once a month .:::::,
page 249.
Driving style
Driving fast around curves, heavy acceleration and hard braking
increase tire wear.
Rotating tires for more even wear
For all four tires on your vehicle to have the same service life, we
recommend that the front and rear tires are rotated according to the
tire manufacturer's suggested tire rotation intervals. Please
remember the following:
• Tire rotation intervals may differ from the vehicle service inter­
vals outlined in your Warranty
& Maintenance Booklet.
• The longer one tire is used in one location on the vehicle, the
more it wears at certain points; therefore, we recommend that you
follow the tire manufacturer 's suggested tire rotation intervals.
• Vehicles with front-wheel drive experience more tread wear on
the front wheels compared to all-wheel drive (quattro®l .
• Please rotate tires as shown .:::::, fig. 176.
• Extra care must be taken when rotating direction -specific tires
:::::, page 277.
Wheel balancing
The wheels on new vehicles are balanced. However, various situa­
tions during everyday driving can cause them to become unbal ­
anced, resulting in vibrations you can usually feel through the
steering wheel.
Unbalanced wheels must be rebalanced to avoid excessive wear on
steering, suspension and tires. A wheel must also be rebalanced
when a new tire is installed. _,,
Vehicle care I I Technical data

___ T_ i_ r_e _s_ a_ n_ d_ w_ h_ e_ e _ ls _________________________________________________ _
Incorrect wheel alignment
Incorrect wheel alignment can cause excess ive tire wea r, im pairing
the safety of the vehic le. If tires show excessive wear, have the
whee l alignment c hecked by an au th o rize d Audi deale r or qualifie d
wo rkshop.
All Wheel Drive
Vehicles with quattro® must always have tires of the same size, c ons truc tion and tread type. F or details see ~ page
19 4.
& WARNING
Sudden tire failure can lead to los s of control, a crash and serious
personal injury !
• Never drive a vehicle when the tread on any tire is worn down
to the wear indicators .
• Worn tires are a safety hazard, they do not grip well on wet
roads and increase your risk of "hydroplaning " and loss of control .
• Always keep chemicals that can cause tire dam age , such as
grease, oil , gasoline and brake fluid aw ay from tires .
• Tires age even if they are not being used and can fail suddenly ,
especially at high speeds. Tires that are more than 6 years old can
only be used in an emergency and then with special care and at
lower speeds .
• Never mount used tires on your vehicle if you are not sure of
their "previous history." Old used tires may have been damaged
even though the damage cannot be seen that can lead to sudden
tire failure and los s of veh icle control. •
New tires and replacing tires and wheels
New t ires and wheels h ave t o be broke n in.
Fig . 177 T ir e specif ication cod es on the sidewall of a tir e
No.
©
0
©
©
©
©
Description
Passenger car tire (where applicable)
Nominal width of tire in millimeters
Ratio of height to width (aspect ratio)
Radial
Rim diameter code
L o ad in dex and s peed ra ting

Tires a nd wh eels -
----------------
•
0
-
©
®
U.S. DOT tire identification number
Audi Original tire
Tire ply composition and materials used Maximum load rating
Treadwear, traction and temperature grades
@ Maximum permissible inflation pressure
The tires and rims are essential parts of the vehicle 's design. The
tires and rims approved by Audi are specially matched to the char­
acteristics of the vehicle and can make a major contribution to good
road hold ing and safe handling when in good cond ition and prop­
erly inflated =>& .
We recommend that a ll work on tires and wheels be performed by
an authorized Audi dealer. They are familiar with recommended
procedures and have the necessary special tools and spare parts as
well as the proper facilities for disposing of the old tires.
Authorized Audi dea lers have the necessary info rmation about tech ­
nical requirements for insta lling or changing tires and rims.
R epl ac ing tires and wheels
Tires shou ld be replaced at least in pairs and not individual ly (for
examp le both front tires or both rear tires together).
Be sure to read and heed the tire pressure monitoring sys tem*
information=>
page 256.
A lways buy replacement radial tires that have the same specifica ­
tions as the tires approved for your vehicle by Audi. Rep lacement
tires must always have the same load rating specification as the
origina l equipment or approved optional t ires listed in the table
=>
page 246.
Audi -appr oved spec ification tires are spec ially matched to your
vehicle and its load limits, and can contribute to the important road- holding, driving characteristics, and safety of the vehicle
. The table
( =>
page 246) lists specifications of the tires approved for the Audi
models covered by your Owner's Literature.
The tire pressure labe l located either on driver's side 8 -pi llar or
inside the fuel fi ller flap(=>
page 246, fig. 174) lists the specifica ­
tions of the original equipment tires installed on your vehicle at the
ti me it was manufactured.
Federa l law requires tire manufacturers to place standardized infor ­
mation on the sidewa ll of all tires =>
page 254, fig . 177. This informa ­
t ion identifies and describes the fundamental characteristics, the
qua lity grade of the ti re and also provides a tire identification
number for safety standard certificat ion and in case of a recal l.
Tire specificat ions
Knowledge of tire specifications makes it easier to choose the
co rrect t ires . Radial tires have the tire specifications marked on the
sidewall, for example :
P225 / 45 R 17 91H XL
This contains the fo llowing informa tion:
P Indicates the ti re is for passenger cars (where applicab le)
225 No minal tire width i n mm of the tire fro m sidewall edge to side -
wa ll edge. In general, the larger the number, the wider the tire
45 Height/width ratio in percent (aspect ratio)
R Tire construction: Radial
17 Rim diameter code (in inches)
91 Load rating code
H Speed rating lette r code
XL (or "xi", "EX TRA LOA D" or "RF") indicates that the tire is "Rein­
forced" or an "Extra Load" ti re
M +S (o r "M/S") Indicates that the tire has some mud and snow capa ­
bility
The tires could a lso have the information of direct ion of rotation
=>
page 242.
Vehicle care I t •

-~_T_ ir_e_ s_ a_ n_d _ w_ h_ e_e _l_s _________________________________________________ _
Tire manuf acturin g date
The manufacturing date is a lso indicated on the tire sidewall
(possibly only on the
inner side of the wheel):
"DOT ... 2209 ... " means, for example, that the tire was produced in
the 22nd week of 2009.
Sp eed rating (l ett er code )
The speed rating letter code on the wheels indicates the maximum
permissible road speeds=>
& in "Winter tires" on page 259.
P up to 93 mph (150 km/h)
Q up to 99 mph (158 km/h)
R up to 106 mph (170 km/h)
S upto110mph(180km/h)
T upto118mph(190km/h)
U up to 124 mph (200 km/h)
H up to 130 mph (2 10 km/h)
V up to 149 mph (240 km/h)4>
Z over 149 mph (240 km/h)4>
W up to 168 mph (270 km/h)41
Y up to 186 mph (298 km/h)4>
Your vehicle is normally factory equipped with tires, which possess
excellent driving characteristics and give your Audi optimum
driving comfort . An e lectronic speed limiter=>
page 21 will normally
prevent your vehicle from going faster than the t ire speed rating
=> & .
U.S . D OT T ire Identifi cation Number (TIN ) an d tire
m anuf actur e date
This is the tire's "seria l number" . It begins with the letters "DOT"
and indicates that the tire meets all federal standards . The next two
numbers or letters indicate the plant where it was manufactured,
and the last four numbers represent the week and year of manufac-
41 For tires with a maximum speed capab il ity over 149 mph (240 km/h), tire
manufacturers sometimes use the letters "ZR."
ture. For example, the numbers 2209 mean that the tire was
produced in the 22nd week of 2009 . The other numbers are
marketing codes that may or may not be used by the tire manufac­
turer . This information is used to contact consumers if a tire defect
requires a recall.
Audi Original tire
T ires with the identification "AO" or "RO" have been specially
matched with your Audi . We recommend using o nly these tires
because they meet the highest standards regarding safety and
driving characteristics when used correctly. Your authorized Audi
dea ler will glad ly provide you with more information.
Maximu m Load Rating
This number indicates the maximum load in kilograms and pounds
that can be carried by the tire .
Tire qu alit y g ra di ng fo r tr eadw ear, tr ac tio n, and
temp era ture re sista n ce
Tread wear, traction and temperature grades=> page 258.
Max imum P ermi ssible Infl ation Pre ssure
This number is the greatest amount of air pressure that should ever
be put in the tire under norma l driv ing condit ions.
Repl acin g tire s or rims on vehicl es e quipp ed with t ir e
pre ssure m onit orin g s yst em *
The wheels on your vehicle are equipped with a sensor which
constantly monitors the air pressure inside the tire, and then trans ­
mits this information to the tire pressure monitoring system* . If you
are going to replace the whee l rims on your vehicle, make sure the
new rims also have these sensors. The sensors must be compatible
with the tire pressure monitoring system* on your veh icle.
I f you install rims that do not have the sensors or have sensors
which are not compatible, then the tire pressure monitoring
system* wil l not work properly . In this case, the tire pressure moni-
~

________________________________________________ T_ i _r_e _s_ a_n_ d_ w_ h_ e_e _ l_s __ !II
•
to ring s yst em * would not b e ab le to moni tor the tire pr essur e or
war n yo u if i t is nec essa ry.
• T he battery ins ide of the tire pressure s ensor has a l imited
service life.
• Always driv e with the va lv e stem caps s ecure ly m ounted. We
r e co mm end usi ng fact ory insta lled valve stem cap s. Ask y our a utho­
rized Audi d ealer to replac e lost valve stem caps .
T he installat ion of replacement tires with steel cord body plies in
t he ti re s id ew all m ay ca use ma lfun ction o f th e tire press ure m oni­
toring system *, and is not recommended (co rd mater ial information
i n mo lded on t he tire sid ewa ll).
Always check your t ire pressure mo nitoring system* indicator after
r eplaci ng o ne or more tir es o n you r veh ic le . If t he ti re p ressu re
mo nito ring syste m* in dicato r flashes o r is ill um in ated, your s ystem
is not working p rope rly . Yo ur replacement t ire might be inco mpat ­
i b le with you r tir e p ressure mon itori ng sys te m *, or so me comp o­
nent of the tire pressure monitoring system * may be damaged .
& WARNING
• Using incorrect or unmatched tires and / or wheels or improper
tire and wheel combinations can lead to loss of control , collision
and serious personal injury .
• Always use tires , rims and wheel bolts that meet the specifica ­
tions of original factory-installed tires or other combinations that
have been specifically approved by the vehicle manufacturer .
• Tires age even if they are not being used and can fail suddenly,
espe cially at high speeds . Tires that are more than 6 years old can
only be used in an emergency and then with special care and at
lower speeds.
• Never mount used tires on your vehicle if you are not sure of
their "previous history. " Old used tires may have been damaged
even though the damage cannot be seen that can lead to sudden
tire failure and loss of vehicle control.
& WARNING (continued )
• All four wheels must be fitted with radial tires of the same type,
size {rolling circumference ) and the same tread pattern. Driving
with different tires reduces vehicle handling and can lead to a loss
of control.
• If the spare tire is not the same as the tires that are mounted
on the vehicle -for example with winter tires -only use the spare
tire for a short period of time and drive with extra care . Refit the
normal road wheel as soon as safely possible.
• Never drive faster than the maximum speed for which the tires
on your vehicle are rated because tires that are driven faster than
their rated speed can fail suddenly .
• Overloading tires cause heat build-up , sudden tire failure ,
including a blowout and sudden deflation and loss of control.
• Temperature grades apply to tires that are properly inflated and
not over or underinflated.
• For technical reasons it is not always possible to use wheels
from other vehicles -in some cases not even wheels from the
same vehicle model.
• If you install wheel trim discs on the vehicle wheels , make sure
that the air flow to the brakes is not blocked . Reduced airflow to
the brakes can them to overheat , increasing stopping distances
and causing a collision .
• Run flat tires may only be used on vehicles that were equipped
with them at the factory . The vehicle must have a chassis designed
for run flat tires and a factory-installed tire pressure monitoring
system* that indicates a loss of tire pressure . Incorrect use of run
flat tires can lead to vehicle damage or accidents . Check with an
authorized Audi dealer or tire specialist to see if your vehicle can
be equipped with run flat tires . If run flat tires are used , they must
be installed on all four wheels . Mi xing tire types is not permitted. _,.
Vehicle care
I t •

-~_T_ ir_e_ s_ a_ n_d _ w_ h_ e_e _l_s _________________________________________________ _
0 Note
• For technical reasons, it is not generally possible to use the
wheel rims from other vehicles. This can hold true for wheels of the
same vehicle type.
• If the spare tire is different from the tires that you have mounted
on your vehicle (for example winter tires or wide profile t ires), then
use the spare tire for a short period of time only and drive with extra
care. Replace the f lat tire with the tire matching the others on your
vehic le as soon as possib le.
• If you put different whee ls and tires on your vehic le (e .g. winter
whee ls and tires), you must be certain that the wheels and tires are
compatible with the tire pressure monitoring system*. Otherwise
the system will register a malfunction and a fault message wi ll be
displayed. For more information, contact your authorized Aud i
dea ler.
(D Note
• When installing new tires, be careful not to damage the valves or
tire pressure monitoring system* sensors.
• Never drive without the valve stem cap. The valves could get
damaged.
• If the sensors must be replaced, then the valve must also be
replaced at the same time.
<£> For th e sake of the environm ent
Dispose of o ld tires in accordance with the loca l requirements. •
Uniform tire quality grading
• Tread wear
• Traction AA A B C
• Temperature A B C Quality grades can be found where applicable on the tire side wal
l
between tread shoulder and maximum section width~
page 254,
fig. 177 .
For exa mple: Tread wear 200, Traction AA , Temperature A.
All passenger car tires must conform to Federal Safety Requ ire­
ments in addition to these grades.
T rea d w ear
The
tread wear grade is a comparative rating based on the wear rate
of the tire when tested under controlled condit ions on a specified
government test course .
Fo r example, a tire graded 150 wou ld wear one and one hal f (1 1/2)
times as well on the government course as a tire graded 100.
The relative performance of tires depends upon the actua l condi ­
tions of their use, however, and may depart significantly from the norm due to variations in driving habits, service practices and differ ­
ences in road characteristics and climate .
Tr act ion
The
traction grades, from highest to lowest, are AA, A, Band C.
T hose grades represent the tire 's ability to stop on wet pavement as
measured under contro lled co nditions on specified government
test surfaces of asphalt and concrete. A tire marked C may have
poor traction performance
~ & .
Temp erature
T he
temperature grades are A (the highest), B , and C , represent ing
the tire's resistance to the generation of heat and its abi lity to dissi ­
pate heat when tested under control led conditions on a specified
indoor laboratory test wheel.
Susta ined high temperature can cause the mater ial of the tire to
degenerate and reduce tire life, and excessive temperature can lead
to sudden tire failure~& .
T he grade C corresponds to a leve l of performance which a ll
passenger car tires must meet under the Federal Motor Vehicle