AUDI A8 2021 Owners Manual

4N0012721BF
Wheels

Wheels Wheels
and Tires
General information
> Check your tires regularly for
damage, such as punctures,
cuts, cracks, and bulges. Remove
foreign objects from the tire
tread.
>If driving over curbs or similar
obstacles, drive slowly and ap-
proach the curb at an angle.
> Have faulty tires or rims re-
placed immediately.
>Protect your tires from oil,
grease, and fuel.
>Mark tires before removing
them so that the same running
direction can be maintained if
they are reinstalled.
>Lay tires flat when storing and
store them ina cool, dry location
with as little exposure to light as
possible.

A WARNING
—Never drive faster than the
maximum permitted speed for
your tires. This could cause the
tires to heat up too much. This
increases the risk of an acci-
dent because it can cause the
tire to burst.


—Always adapt your driving to
the road and traffic condi-
tions. Drive carefully and re-
duce your speed on icy or slip-
pery roads. Even winter tires
can lose traction on black ice.

() Note
—Please note that summer and
winter tires are designed for
the conditions that are typical
in those seasons. Audi recom-
mends winter tires during the
winter months. Low tempera-
tures significantly decrease
the elasticity of summer tires,
which affects traction and
braking ability. If summer
tires are used in very cold tem-
peratures, cracks can form on
the tread bars, resulting in
permanent tire damage that
can cause loud driving noise
and unbalanced tires.
—Burnished, polished or
chromed rims must not be
used in winter driving condi-
tions. The surface of the rims
does not have sufficient corro-
sion protection for this and
could be permanently dam-
aged by road salt or similar
substances.
289

Wheels

Tire designations
© 2 2 x ©
oO


Fig. 187 Tire designations on the side-
wall
@ Tires for passenger vehicles
(if applicable)
“P” indicates a tire for a passen-
ger vehicle. “T” indicates a tire
designated for temporary use.
@ Nominal width
Nominal width of the tire be-
tween the sidewalls in millime-
ters. In general: the larger the
number, the wider the tire.
@) Aspect ratio
Height/width ratio expressed asa
percentage.
290
@ Tire construction
“R” indicates a radial tire.
©) Rim diameter
Size of the rim diameter in inches.
© Load index and speed rating
The load index indicates the tire's
load-carrying capacity.
The speed rating indicates the
maximum permitted speed. Also
see > A in General information on
page 289.
“EXTRA LOAD”, “xl” or “RF” indi-
cates that the tire is reinforced or
is an Extra Load tire.






Speed rat- /Maximum permitted speed
ing
P up to 93 mph (150 km/h)
Q up to 99 mph (160 km/h)
R up to 106 mph (170 km/h)
Ss up to 110 mph (180 km/h)
T up to 118 mph (190 km/h)
U up to 124 mph (200 km/h)
H up to 130 mph (210 km/h)
Vv up to 149 mph (240 km/h)?
Zz above 149 mph (240 km/h)?)
w up to 168 mph (270 km/h)?
Y up to 186 mph (300 km/h)

@ For tires above 149 mph (240 km/h),
tire manufacturers sometimes use the
code “ZR”.

4N0012721BF
Wheels

@ US DOT number (TIN) and
manufacture date
The manufacture date is listed on
the tire sidewall (it may only ap-
pear on the inner side of the tire):
DOT... 2220...
means, for example, that the tire
was produced in the 22nd week of
the year 2020.
Audi Original Tires
Audi Original equipment tires
with the designation “AO” have
been specially matched to your
Audi. When used correctly, these
tires meet the highest standards
for safety and handling. An au-
thorized Audi dealer or author-
ized Audi Service Facility will be
able to provide you with more in-
formation.
@) Mud and snow capability
“M/S” or “M+S” indicates the tire
is suitable for driving on mud and
snow. /4\ indicates a winter tire.
Composition of the tire cord
and materials
The number of plies indicates the
number of rubberized fabric lay-
ers in the tire. In general: the
more layers, the more weight a
tire can carry. Tire manufacturers
must also specify the materials
used in the tire. These include
steel, nylon, polyester and other
materials.
@) Maximum permitted load
This number indicates the maxi-
mum load in kilograms and
pounds that the tire can carry.
@ Uniform tire quality grade
standards for treadwear,
traction and temperature
resistance
Treadwear, traction, and tempera-
ture ranges > page 306.
@ Running direction
The arrows indicate the running
direction of unidirectional tires.
You must always follow the speci-
fied running direction
=> page 322.
Maximum permitted
inflation pressure
This number indicates the maxi-
mum pressure to which a tire can
be inflated under normal operat-
ing conditions.
291

Wheels

Glossary of tire and loading
terminology
Accessory weight
means the combined weight (in
excess of those standard items
which may be replaced) of auto-
matic transmission, power steer-
ing, power brakes, power win-
dows, power seats, radio, and
heater, to the extent that these
items are available as factory-in-
stalled equipment (whether in-
stalled or not).
Aspect ratio
means the ratio of the height to
the width of the tire in percent.
Numbers of 55 or lower indicate a
low sidewall for improved steer-
ing response and better overall
handling on dry pavement.
Bead
means the part of the tire that is
made of steel wires, wrapped or
reinforced by ply cords and that is
shaped to fit the rim.
Bead separation
means a breakdown of the bond
between components in the bead.
292
Cord
means the strands forming the
plies in the tire.
Cold tire inflation pressure
means the tire pressure recom-
mended by the vehicle manufac-
turer for a tire of a designated
size that has not been driven for
more than a couple of miles (kilo-
meters) at low speeds in the three
hour period before the tire pres-
sure is measured or adjusted.
Curb weight
means the weight of a motor ve-
hicle with standard equipment in-
cluding the maximum capacity of
fuel, oil, and coolant, air condi-
tioning and additional weight of
optional equipment.
Extra load tire
means a tire designed to operate
at higher loads and at higher in-
flation pressures than the corre-
sponding standard tire. Extra load
tires may be identified as “XL”,
“xl”, “EXTRA LOAD”, or “RF” on
the sidewall.

4N0012721BF
Wheels

Gross Axle Weight Rating
(“GAWR’”)
means the load-carrying capacity
of a single axle system, measured
at the tire-ground interfaces.
Gross Vehicle Weight Rating
(“GVWR”)
means the maximum total loaded
weight of the vehicle.
Groove
means the space between two ad-
jacent tread ribs.
Load rating (code)
means the maximum load that a
tire is rated to carry for a given in-
flation pressure. You may not find
this information on all tires be-
cause it is not required by law.
Maximum load rating
means the load rating for a tire at
the maximum permissible infla-
tion pressure for that tire.
Maximum loaded vehicle
weight
means the sum of:
(a) Curb weight
(b) Accessory weight
(c) Vehicle capacity weight, and
(d) Production options weight
Maximum (permissible)
inflation pressure
means the maximum cold infla-
tion pressure to which a tire may
be inflated. Also called “maxi-
mum inflation pressure.”
Normal occupant weight
means 150 lbs. (68 kilograms)
times the number of occupants
seated in the vehicle up to the to-
tal seating capacity of your vehi-
cle.
Occupant distribution
means distribution of occupants
in a vehicle.
Outer diameter
means the overall diameter of an
inflated new tire.
Overall width
means the linear distance be-
tween the exteriors of the side-
walls of an inflated tire, including
elevations due to labeling, deco-
rations, or protective bands or
ribs.
Ply
means a layer of rubber-coated
parallel cords.
293

Wheels

Production options weight
means the combined weight of
those installed regular production
options weighing over 5 lbs.
(2.3 kg) in excess of those stand-
ard items which they replace, not
previously considered in curb
weight or accessory weight, in-
cluding heavy duty brakes, ride
levelers, roof rack, heavy duty
battery, and special trim.
Radial ply tire
means a pneumatic tire in which
the ply cords that extend to the
beads are laid at substantially
90 degrees to the centerline of
the tread.
Recommended inflation
pressure
see > page 292, Cold tire infla-
tion pressure.
Reinforced tire
means a tire designed to operate
at higher loads and at higher in-
flation pressures than the corre-
sponding standard tire. Rein-
forced tires may be identified as
“XL”, “xl”, “EXTRA LOAD”, or “RF”
on the sidewall.
294
Rim
means a metal support for a tire
or a tire and tube assembly upon
which the tire beads are seated.
Rim diameter
means nominal diameter of the
bead seat. If you change your
wheel size, you will have to pur-
chase new tires to match the new
rim diameter.
Rim size designation
means rim diameter and width.
Rim width
means nominal distance between
rim flanges.
Sidewall
means that portion of a tire be-
tween the tread and bead.
Speed rating (letter code)
means the speed at which a tire is
designed to be driven for extend-
ed periods of time. The ratings
range from 93 mph (150 km/h)
to 186 mph (298 km/h) > table
on page 290. You may not find
this information on all tires be-
cause it is not required by law.
The speed rating letter code,
where applicable, is molded on
the tire sidewall and indicates the >

4N0012721BF
Wheels

maximum permissible road
speeds. See also > A in General
information on page 289.
Tire pressure monitoring
system
means a system that detects
when one or more of a vehicle's
tires are underinflated and illumi-
nates a low tire pressure warning
telltale.
Tread
means that portion of a tire that
comes into contact with the road.
Tread separation
means pulling away of the tread
from the tire carcass.
Treadwear indicators (TWI)
means the projections within the
principal grooves designed to give
a visual indication of the degrees
of wear of the tread. See
=> page 298, Treadwear indicator
for more information on measur-
ing tire wear.
Uniform Tire Quality Grading
is a tire information system devel-
oped by the United States Nation-
al Highway Traffic Safety Adminis-
tration (NHTSA) that is designed
to help buyers make relative com-
parisons among tires. The UTQG is
not a safety rating and not a guar-
antee that a tire will last fora
prescribed number of miles (kilo-
meters) or perform ina certain
way. It simply gives tire buyers
additional information to com-
bine with other considerations,
such as price, brand loyalty and
dealer recommendations. Under
UTQG, tires are graded by the tire
manufacturers in three areas:
treadwear, traction, and tempera-
ture resistance. The UTQG infor-
mation on the tires, molded into
the sidewalls.
U.S. DOT Tire Identification
Number (TIN)
This is the tire’s “serial 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 manufac-
tured, and the last four numbers
represent the week and year of
manufacture. For example,
DOT... 2220...
means that the tire was produced
in the 22nd week of 2020. The
other numbers are marketing co-
des that may or may not be used >
295

Wheels

by the tire manufacturer. This in-
formation is used to contact con-
sumers if a tire defect requires a
recall.
Vehicle capacity weight
means the rated cargo and lug-
gage load plus 150 lbs. (68 kilo-
grams) times the vehicle's desig-
nated seating capacity.
Vehicle maximum load on the
tire
means that load on an individual
tire that is determined by distrib-
uting to each axle its share of the
maximum loaded vehicle weight
and dividing by two.
Vehicle normal load on the tire
means that load on an individual
tire that is determined by distrib-
uting to each axle its share of the
curb weight, accessory weight,
and normal occupant weight (dis-
tributed in accordance with > ta-
ble on page 301) and dividing by
two.
Occupant loading and distri-
bution for vehicle normal load
for various designated seating
capacities
Refer to the tire inflation pressure
label > page 299, fig. 190 for the
296
number of seating positions. Re-
fer to the table > table on
page 301 for the number of peo-
ple that correspond to the vehicle
normal load.
New tires or wheels
Audi recommends having all work
on tires or wheels performed by
an authorized Audi dealer or au-
thorized Audi Service Facility.
These facilities have the proper
knowledge and are equipped with
the required tools and replace-
ment parts.
>New tires do not yet have the
optimal gripping properties.
Drive carefully and at moderate
speeds for the first 350 miles
(500 km) with new tires.
> Only use tires with the same de-
sign, size (rolling circumfer-
ence), and as close to the same
tread pattern as possible on all
four wheels.
>Do not replace tires individually.
At least replace both tires on the
same axle at the same time.
> Audi recommends using Audi
Genuine Tires. If you would like
to use different tires, please
note that the tires may perform >

4N0012721BF
Wheels

differently even if they are the
same size > A.
>If you would like to equip your
vehicle with a tire and rim com-
bination that is different from
what was installed at the facto-
ry, consult with an authorized
Audi dealer or authorized Audi
Service Facility before making a
purchase > A.
Because the spare tire® is differ-
ent from the regular tires instal-
led on the vehicle (such as winter
tires or wide tires), only use the
spare tire* temporarily in case of
emergency and drive carefully
while it is in use. It should be re-
placed with a regular tire as soon
as possible.
All four wheels must be equipped
with tires that are the same brand
and have the same construction
and tread pattern so that the
drive system is not damaged by
different tire speeds. For this rea-
son, in case of emergency, only
use a Spare tire* that is the same
circumference as the regular tires.


Z\ WARNING
—Do not use steel rims that are
17 inches or larger. Otherwise,


damage to the vehicle and an
accident could result.
—Only use tire/rim combina-
tions and suitable wheel bolts
that have been approved by
Audi. Otherwise, damage to
the vehicle and an accident
could result.
—For technical reasons, it is not
possible to use tires from oth-
er vehicles. In some cases, you
cannot even use tires from the
same vehicle model.
—Make sure that the tires you
select have enough clearance
to the vehicle. Replacement
tires should not be chosen
simply based on the nominal
size, because tires with a dif-
ferent construction can differ
greatly even if they are the
same size. If there is not
enough clearance, the tires or
the vehicle can be damaged
and this can reduce driving
safety and increase the risk of
an accident.
—Only use tires that are more
than six years old when abso-
lutely necessary and drive
carefully when doing so.
—Do not use run-flat tires on
your vehicle. Using them when

297

Wheels


not permitted can lead to ve-
hicle damage or accidents.
—If you install wheel covers on
the vehicle, make sure they al-
low enough air circulation to
cool the brake system. If they
do not, this could increase the
risk of an accident.

Tire wear and damage

B4H-0415

a
Fig. 188 Tire profile: treadwear indica-
tor
Tire wear
Check the tires regularly for wear.
—Inflation pressure that is too low
or high can increase tire wear
considerably.
—Driving quickly through curves,
rapid acceleration, and heavy
braking increase tire wear.
—Have an authorized Audi dealer
or authorized Audi Service Facili-


D Obey any applicable regulations in the
country where the vehicle is being oper-
ated.
298
ty check the wheel alignment if
there is unusual wear.
—Have the wheels rebalanced if an
imbalance is causing noticeable
vibration in the steering wheel.
If you do not, the tires and other
vehicle components could wear
more quickly.
Treadwear indicator
Original equipment tires contain
treadwear indicators in the tread
pattern, which are bars that are
1/16 inch (1.6 mm) high and are
spaced evenly around the tire per-
pendicular to the running direc-
tion > fig. 188. The letters “TWI”
or triangles on the tire sidewall
indicate the location of the tread-
wear indicators.
The tires have reached the mini-
mum tread depth !) when they
have worn down to the treadwear
indicators. Replace the tires with
new ones > A.
Tire rotation
Rotating the tires regularly is rec-
ommended to ensure the tires
wear evenly. To rotate the tires, >