2013 AUDI A8 tire size

Driving with your
quattro ®
With All Wheel Drive, all four wheels are driv­
en .
Gene ral inform ation
W ith All Whee l Drive, power is distributed to
all four wheels . This happens automatically
depending on your driving style and the road
conditions at the t ime. See also
t::;> page 198.
W ith the spo rt differential*, power d istribu­
tion to the rear wheels is variable and can be
adj usted with Aud i drive select*
t::;> page 109.
Always read and fo llow safety precautions
c:> .&. .
Winter t ires
When driving in the winter , your vehicle with
All Wheel Dr ive has an advantage, even with
regular t ires. In winter road conditions it may
be advisable to mount winter tires (or all-sea­
son tires) for improved driveability and brak­ ing: these tires must be mounted on
a ll four
w he els .
See also c:> page 264, Winter tires.
Sn ow cha ins
Where snow cha ins a re mandatory on certa in
roads, th is normally a lso applies to vehicles
with A ll Wheel Drive
c:> page 265, Snow
chains .
Replacing whe els/ tires
Vehicles w ith All Whee l Dr ive must always
have tires of the same size. Also avoid t ires
with different tread depths. For details see
page
c:> page 260, New tires and replacing
tires and wheels .
Off-Road driving?
Your Audi does not have enough ground clear­
ance to be used as an off-road vehicle.
It is
therefore best to avoid rough tracks and un ­
even terrain as much as possible. Also refer to
c:> page207.
Int ellig ent technolog y 203
A WARNING
Always adjust your driv ing to road and traf­
fic conditions. Do not let the extra safety
afforded by All Wheel Dr ive tempt you into
taking extra risks .
- Although the All Wheel Drive is very ef­
fective, always remember that braking capacity is lim ited by tire t raction. You
should therefore not d rive at excessive
speeds on icy or slippery road surfaces.
- On wet road surfaces, be careful not to
drive too fast because the fron t wheels
could begin to slide on top of the water (aquaplaning) . If this should occur, yo u
will have no warning from a s udden in­
crease in engine speed as w ith a front­
wheel drive veh icle. Always drive at
speeds which are su ited to the road con­
ditions - risk of crash.
Energy management
Starting ability is optimized
Energy management controls the distribution
of electrical energy and thus optimizes the
availability of electrical energy for starting
the engine .
If a vehicle with a conve ntiona l energy system
is not drive n for a long per iod of t ime, the bat­
tery is discharged by idling current consume rs
(e.g . immobilizer). In certain circumstances it
can resu lt in the re being insuff icient energy
available to start the engine.
Intelligent energy management in your vehi­
cle handles the distribution of e lectrica l ener­
gy. Starting ability is marked ly improved and
the life of the battery is extended.
Basica lly, energy management consists of
b atte ry diagno sis, i dling current man age­
ment
and d y namic ene rg y management .
Battery diagno sis
Battery diagnosis continuously determines
the sta te of the battery. Sensors determine
battery voltage, battery current and battery
Ii),,
•
•

Groove
means the space between two adjacent tread
ribs.
Load rating (code)
means the maximum load that a tire is rated
to carry for a g iven inflation pressure. You
may not find this information on all tires be­
cause it is no t req uired by law.
Maximum load rating
means the load rating for a t ire at the max i­
mum permissible inflation 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 inflation pressure
to which a tire may be inflated. Also called "maximum inflation pressure."
Normal occupant weight
means 150 lbs. (68 kilograms) times the
number of occupants seated in the vehicle up
to the total seating capacity of your vehicle.
Occupant distribution
means distribution of occupants in a vehicle.
Outer diameter
means the overa ll diamete r of an inflated new
tire.
Overall width
means the linear distance between the exteri­
ors of the sidewalls of an inflated tire, includ ­
in g elevations due to labeling, decorations, or
protective bands or ribs.
Ply
means a layer of rubber-coated parallel cords.
Tires and wheels 251
Production options weight
means the combined weight of those installed
regular production options we ighing over 5
lbs. (2.3 kg) in excess of those standard items
which they replace, not previously considered
in curb weight or accessory weight, including
heavy duty brakes, ride levelers, roof rack,
heavy duty battery, and spec ial tr im .
Radial ply tire
means a pneumatic tire in which the ply cords
that extend to the beads are laid at substan­
tia lly 90 degrees to the center line of the
tread .
Recommended inflation pressure
see¢ page 250, Cold tire inflation pressure.
Reinforced tire
means a t ire design to operate at higher loads
and at h igher inflation pressures than the cor­
responding standard tire. Reinforced tires
may be identified as "XL", "xl" , "EXTRA LOAD",
or "RF" on the sidewa ll.
Rim
means a metal support for a tire or a t ire and
tube assembly upon which the tire beads are
seated.
Rim diameter
means nom inal diameter of the bead seat. If
you change your wheel s ize, you will have to
purchase new tires to match the new rim di­
ameter.
Rim size designation
means r im diameter and width .
Rim width
means nominal distance between rim flanges .
Sidewall
means that portion of a tire between the
tread and bead.
•
•

Tires and wheels 253
Occupant loading and distribution for vehicle normal load for various d esignated seat ing
capaci tie s
Designated seating capacity ,
number of occupants Vehicle normal load
, number Occupant distribution in a nor-
of occupants _____ mally loaded vehicle
4 2 _________ 2infront
5 3 2 in front, 1 in back seat
Cold tire inflation pressure
Tire pressure affects the overall handling, performance and safety of a vehicle.
Fig . 20 4 Tire pressu re lab el: located o n driv e r's side B­
p ill ar
Tire pressure genera lly refers to the amo unt
of air in a tire that it needs it to do its job and
safely car ry the combined load of the en tire
vehicle and its contents . T ire pressure is
measured in kilopasca ls (kPa) , the interna ­
tional measu ring unit and in pounds per
s quare inch (PSI). Tire p ressure is based in
part on the vehicle's design and load limit -
the greatest amount of weight that the vehi ­
cle can carry safe ly and the t ire size . The prop­
e r tire pressu re is frequent ly referred to as the
" recommended cold tire inf lation pressure ."
Air in the tires expands when the ti re heats up
bec ause of interna l fri ct ion when it flexes in
use. The tire p ress ure is higher when the tire
has warmed up than when it is "cold ." It is the
inflat ion p ressure in a "cold" tire that counts.
Therefore, you should never let air out of a
warm tire to match "cold tire inflation p res­
sure" recommendations. The t ires would the n
be underi nflated and could fail suddenly .
Maintaining proper tire pre ssure is one of the
most important things you can do to he lp
avoid sudde n tire failure . Underinflated t ires
are a majo r cause of sudden tire failure . Keep­
i ng tires at the r ight pressure is also impor-
-"' --~ - -,e
• (:::=~. ~: I =: I :,.. I)( ::: ) l3 n,........,..,.__...,~ ........ ....,_...... • ... _ .. , ....................................... ..,_ "" ..
-""u
--
-...........
- KPA. a PSI
- KPA.
a PSI
-KPA. a PSI
Fi g. 20 S Tire pres sure label
tant for safe and respo nsive ve hicle han dling,
tr action, braking and load carrying.
Tir e pres­
sure s are particul arly important when the
vehicle i s being dr iven at higher speeds, and
then e speciall y when hea vily loaded even
within the pe rmissible load- carrying capaci­
ties app roved for your veh icle .
The recommended t ire pressures for your Audi
depen d on the kind of tires on your vehicle
and the n umber of passengers and/or amount
of luggage you wi ll be transporting.
The tire pressure label is located on the driv­
er 's side B-pillar. The tire pressure labe l lists
the recommended cold t ire inflat ion pressures
for the vehicle at its maximum capac ity
weight and tires that were on your veh icle at
the time it was manufactured .
If you wish to improve comfort when operat­
ing the vehicle at normal lo ad (up to 2* /3
occup ants ), you can adjust t ire pressures to
those specified for normal v ehicle load . Be­
fore operating the vehicle at maximum load ,
you must increase the tire pre ssures to tho se
spe cified for maximum v ehicl e load
¢ ,&. . IJi,,-

254 Tires and wheels
Bear in mind that the tire pressure monitoring
system* can only monitor the tire pressures
you have stored . The system does not recog­
nize the load condit ion of your vehicle.
The effectiveness of the tire pressure monitor ­
ing system* will be impaired if you store nor­
mal load pressures but then operate the vehi ­
cle at its max imum load
c:> &. .
See the illustration c:> fig. 204 for the location
of the label on driver's side B-pillar (color of
the act ua l label and exact location on the ve­
hicle will vary slightly). Note
that the following table is accurate at
the time of going to press and is subject to
change. In the event of d iscrepancies, the t ire
pressure label is located on the driver's side B­
pillar always takes precedence.
The table below lists the recommended cold
t ir e inflation pressures for the Audi mode l
covered by your Owner's Literature at the vehi­
cle's capacity weight and the t ire sizes instal­
led on the respective models as orig inal
equipment, or as a factory opt ion.
Tire pressure
Model/En­ gine Tire designation
normal load condition full load condition
AB/AB L: 235/55 R18 104H
3.0
liter 255/45 R19 104H
6
-cyli nd
er 265/40 R20 104H
265/40 R20 104V
275/35 R21103Y XL
AS/AS L: 235/55 R18 104H
4.0
liter 255/45 R19 104H
B-cyli nd
er 265/40 R20 104H
265/40 R20 104V
275/35 R21103Y XL
AS/AB L: 235/55 R18 104H
4.2
liter 255/45 R19 104H
B-cyli nd
er 265/40 R20 104V
ASL:
6.3 liter
12-cylin­
der
265/40 R20 104H
275/35 R21103Y XL
265/40 R20 104V
255/45 R19 104H
265/40 R20 104H
275/35 R21103Y XL
SB: 265/40 R20 104V
4.0
liter 265/35 R21101 Y
B-cyli nd
er 275/35 R21103Y XL
rearal front rear
PSI kPA PSI kPA PSI kPA PSI kPA
260
260
260
240
240
260
260
260
240
260
260
260
240
260
260
240
260
260
240
XL= reinforced or extra load tire. It may also appear as xl, EXTRA LOAD, or RF on the tire side­
wall.
•> normal load condition <=>page 253 .

The correct tire pressure for the spare wheel is
l ocated on a label on the driver's side B-pillar.
Because tec hnical changes may be made to
veh icle equ ipment dur ing the model yea r, a l­
ways compare the tire size designation on the
tire pressure label on your vehicle wit h the
tires on your vehicle . Make s ure that the tire
size information on the veh icle label is the
same as the s ize of the t ires on the vehicle.
This is especially important if the vehicle be ­
longs to someone else or you bought the veh i­
cle with different rims/tires or you boug ht the
ve hicle as a previously owned vehicle.
Remember, your safety and that of your pas­
sengers also depends on mak ing su re that
l oad l imits are not exceeded. Vehicle load in­
cludes everybody and everything in and on the
veh icle. These load limits are technically refer­
red to as the vehicle's Gross Vehicle Weight
Rating ("GVWR") . The Gross Ax le Weight Rat ­
ing ("GAWR") is the maximum load that can
be app lied at each of the veh icle's two axles.
The Gross Vehicle Weight Rating and the
Gross Axle We ight Rating are listed on the
safety compliance st icker label located on the
driver's side B-p illar . The t ire pressure label on
your Aud i lists the maximum combined
weight of a ll of the occupants and luggage or
other cargo that the vehicle can carry. For the
l ocat ion of the tire pressure labe l
c;, fig. 204.
A WARNING
Overloading a vehicle can cause loss of ve­
hicle control, a crash or other accident, se­
rious personal injury, and even death.
- Car rying more weight than yo ur vehicle
was designed to carry will prevent the
vehicle from handling properly and in­
crease the risk of a loss of veh icle con­
trol.
- The brakes on a veh icle that has been
overloaded may not be able to stop the
vehicle within a safe distance .
- Tires on a vehicle that has been overload­
ed can fail suddenly causing loss of con­
t rol and a crash.
Tire s an d wheel s 255
-Always make sure that the total load be­
ing transported - includ ing the weight of
a trailer hitch and the tongue we ight of a
loaded trailer -does not make the vehi­
cle heavier than the vehicle's Gross Vehi­
cle Weight Rating.
A WARNING
- Inco rrect tire pressures and/or underin­
flation can lead to a ser ious or fatal acci­
dent.
- Inco rrect tire pressures and/or underin­
flation cause increased tire wear and can
affect the handling of the vehicle.
- Inco rrect tire pressures and/or underin­
flation can a lso lead to sudden t ire fail­
ure, including a blowou t and sudden de­
flation, caus ing loss of veh icle contro l.
Checking tire pressure
The correct tire pressure for the tires original­
ly installed on your vehicle is listed on the tire
pressvre label located on driver's side 8-pil ­
lar.
T he recommended tire pressures are on the
ti re pressure label and in the table
c;, page 253, Cold tire inflation pressure .This
means that the pressure m ust be checked and
adjusted when the tire has not been dr iven 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 frict ion as it flexes in
use. The tire pressure is h igher when the tire
has warmed up t han when it is "cold."
It is the inflation pressure in a "cold" t ire that
counts. Therefore, you should never let a ir out
of a warm tire to match "Cold t ire inflat ion
pressure" recommendat io ns
c;, page 253 . The
ti res wo uld then be unde rinfl ated and co uld
fail suddenly.
T he tire pressure label on your Audi lists the
recommended co ld tire inflation pressures at
max imum capacity for the new, or ig inal
equipment tires that were on your vehi cle at
1J1>
•
•

260 Tires and wheels
-Vehicles with front-wheel drive experience
more tread wear on the front wheels com­
pared to all-wheel drive (quattro ®).
- Please rotate tires as shown
¢fig. 207.
- Extra care must be taken when rotating di-
rection-specific tires
¢ page 2 78.
Wheel balancing
The wheels on new vehicles are balanced .
H owever, various situations during everyday
driving can cause them to become unbal­
anced , resu lting in vibrations you can usually
feel through the steering wheel.
Unba lanced wheels must be rebalanced to
avoid excessive wea r on steering , suspens ion
and tires . A wheel must also be rebalanced
when a new tire is installed.
Incorrect wheel alignment
Incorrect whee l alignment can cause exces­
sive tire wear, impair ing the safety of the vehi­
cle .
If tires show excess ive wear, have the
wheel alignment checked by an authorized
Audi dealer or qualified workshop.
All Wheel Drive
Vehicles with quattro® must always have ti res
of the same size, construction and tread type.
F or details see
¢page 203.
A WARNING
Sudden tire failure can lead to loss of con­
trol, a crash and serious personal injury!
- Never drive a vehicle when the tread on
any tire is worn down to the wear indica­
tors.
- Worn tires are a safety hazard, they do
not grip well on wet roads and increase
your risk of "hydrop laning" and loss of
control.
- Always keep chemicals that can cause
tire damage, such as grease, oil, gasoline
and brake fluid away from tires.
- Tires age even if they are not be ing 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 specia
l care and at lower
speeds.
- Never mount used tires on your vehicle if
you are not sure of their "previous histo­
ry." Old used tires may have been dam­
aged even though the damage cannot be
seen that can lead to sudden tire failure
and loss of vehicle control.
New tires and replacing tires and wheels
New tires and wheels have to be broken in.
Fig. 208 Tir e spec ificatio n codes on the s idewall of a
tire
No.
©
®
®
0
®
®
@
Description
Passenger car tire (where applicable)
Nominal width of tire in mill imeters
Ratio of height to width (aspect ratio)
Rad ial
Rim diameter code
Load index and speed rating
U.S. DOT tire identification number
Aud i Original tire
Sever snow conditions
Tire ply composition and materials
used
Maximum load rating

-Never mount used tires on your vehicle if
you are not sure of their "previous histo­
ry." Old used tires may have been dam­
aged even though the damage cannot be
seen that can lead to sudden tire failure
and loss of vehicle control.
- All four wheels must be fitted with radial
tires of the same type, size (rolling cir­
cumference) and the same tread pattern.
Driving with different tires reduces vehi­
cle 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 nor­
mal road wheel as soon as safely possi­
ble.
- 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 un­
derinflated .
- 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 ve­
hicle wheels, make sure that the air flow
to the brakes is not blocked. Reduced air­
flow to the brakes can them to overheat,
increasing stopping distances and caus­
ing 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. Incor­
rect use of run flat tires can lead to vehi­
cle damage or accidents. Check with an
authorized Audi dealer or tire specialist
to see if your vehicle can be equipped
Tires and wheels 263
with run flat tires. If run flat tires are
used, they must be installed on all four
wheels. Mixing tire types is not permit­
ted.
@ Note
- For technical reasons, it is not generally
possible to use the wheel rims from oth­
er 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 ve­
hicle (for example winter tires or wide
profile tires), then use the spare tire for a
short period of time only and drive with
extra care. Replace the flat tire with the
tire matching the others on your vehicle
as soon as possible.
- Never drive without the valve stem cap .
The valves could get damaged.
(® For the sake of the environment
Dispose of old tires in accordance with the
local requirements.
Uniform tire quality grading
-Tread wear
- Traction AA A B C
- Temperature ABC
Quality grades can be found where applicable
on the tire side wall between tread shoulder
and maximum section width
~ page 260,
fig. 208 .
For example: Tread wear 200, Traction AA,
Temperature A.
All passenger car tires must conform to Feder­
al 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
unde r contro lled conditions on a specified
government test course. •
•

264 Tire s and wheel s
For example, a tire graded 150 wou ld wear
one and one half (1 1/2) times as well on the
government course as a tire graded
100.
The relat ive perfo rmance of t ires depends
upon the actua l conditions of their use, how ­
ever, and may depart significantly from the norm due to var iat ions in dr iving habits, serv­
ice practices and differences in road character­
istics and climate.
Traction
The traction grades, from highest to lowest,
are AA, A, Band
C. Those grades represent the
tire's ability to stop on wet pavement as
measured under controlled cond it ions on
specif ied government test surfaces of asphalt
and concrete . A tire marked
C may have poor
traction performance
q ,& .
Temp eratu re
The temperature grades are A (the h ighest),
B, and
C, representing the t ire 's resistance to
the generat ion of heat and its ability to dissi­
pate heat when tested under controlled cond i­
tions on a specified i ndoor laboratory test
wheel.
Sustained hig h temperature can cause the
materia l of the tire to degenerate and reduce
tire life, and excessive tempe rature can lead
to sudden ti re failu re
q ,& .
The grade C corresponds to a level of perform­
ance which a ll passenger car tires must meet
u nder the Federa l Moto r Ve hicle Safety Stand­
a rd No.
1 09. G rades Band A represent higher
l eve ls of pe rformance on the labo ratory test
wheel than the m inimum required by law.
A WARNING
T he traction grade assigned to this t ire is
based on straight-ahead b raking traction
tests, and does not incl ude acceleration,
cornering, hydrop lan ing or peak traction
character istics.
A WARNING
The temperature grade for this tire is es­
tablished for a tire that is properly inflated
and not overloaded. Excess ive speed, un­
derinflation, or excessive load ing, either
separa tely or in comb inat ion, can ca u se
h eat bui ld up a nd possib le tire failure.
-
Winter tires
Winter tires can improve vehicle handling on
snow and ice . At temperatures below 45 °F
(7 °C) we recommend changing to winter
tires.
In some heavy snow areas , local gove rnments
may requi re true w in te r or "snow" tires, those
wi th very deeply cut t read . T hese tires sho uld
o n ly be used in pairs and be installed on a ll
fo ur whee ls. Make sure you purchase snow
ti res that are the same size and construction
type as the other tires on your vehicle.
If your vehicle is e quipped w it h all-whee l
drive*, this wi ll improve traction during winter
driving, even with the standa rd tires . Howev ­
er, we strongly recommend that you always
equip all four wheels o n your veh icle w ith cor­
rect ly fitted winter tires or all-season t ires,
when winter road condit ions are expected .
Th is also improves the veh icle's brak ing per­
fo rmance and reduces stoppi ng d ista nces .
Summer tires provide less grip on ice and
snow .
Winter tires (snow tires) must always be fitted on all four wheels .
Ask your authorized A udi dealer or qualified
workshop for permitted
winter ti re size s. Use
on ly rad ial winter tires.
Win ter tires lose their effec tiveness when the
tread is worn down to a depth of
0. 157 inch
(4 mm) .
Only drive w ith w in te r tir es under w inte r con­
di tions. S umme r tires handle bette r when
there is no snow or ice on the roads and the
temperature is above 45
°F (7 °() .