2012 AUDI A8 wheel size

that deployment under these special
conditions is impossible in all conceiva­
ble situations that may happen during
the useful life of your vehicle .
- The Advanced Airbag System can deploy
in accordance with the "low risk" option
under the U .S . Federal Standard if a child
that is heavier than the typical one-year old child is on the front passenger seat
and the other conditions for airbag de­
ployment are met .
- Accident statistics have shown that chil­
dren are generally safer in the rear seat
area than in the front seating position.
- For their own safety, all children, espe­
cially 12 years and younger, should al­
ways ride in the back properly restrained
for their age and size.
Advanced front airbag system
Your vehicle is equipped with a front Advanced
Airbag System in compliance with United
States Federal Motor Vehicle Safety Standard
208 as applicable at the time your vehicle was
manufactured .
T he front Advanced Airbag System supple­
ments the safety belts to provide additional
protection for the driver's and front passeng­
er's heads and upper bodies in frontal crashes .
The airbags inflate only in frontal impacts
when the vehicle deceleration is high enough.
The front Advanced Airbag System for the
front seat occupants is not a substitute for
your safety belts . Rather, it is part of the over­
all occupant restraint system in your vehicle .
Always remember that the airbag system can
only help to protect you, if you are sitting up­
right , wearing your safety belt and wearing it
properly. This is why you and your passengers
must always be properly restrained , not just
because the law requires you to be.
The Advanced Airbag System in your vehicle has been certified to meet the "low risk" re­
quirements for 3 and 6 year-old children on
the passenger side and very small adults on
the driver side. The low risk deployment crite-
Airbag system 147
ria are intended to help reduce the risk of in­
jury through interaction with the front airbag that can occur, for example, by being too
close to the steering wheel and instrument
panel when the airbag inflates.
In addition, the system has been certified to
comply with the "suppression" requirements
of the Safety Standard, to turn off the front
airbag for infants 12 months old and younger
who are restrained on the front passenger
seat in child restraints that are listed in the
Standard
¢ page 168, Child restraints and
Advanced Airbags.
"Suppression" requires the front airbag on the
passenger side to be turned off if:
- a child up to about one year of age is re­
strained on the front passenger seat in one
of the rear -facing or forward-facing infant
restraints listed in Federal Motor Vehicle
Safety Standard 208 with which the Ad­
vanced Airbag System in your vehicle was
certified . For a listing of the child restraints
that were used to certify your vehicle's com­
pliance with the US Safety Standard
¢page 168,
-weight less than a threshold level stored in
the control unit is detected on the front pas­
senger seat.
When a person is detected on the front pas­
senger seat, weighing more than the total
weight of a child that is about 1 year old re­
strained in one of the rear-facing or forward­
facing infant restraints (listed in Federal Mo­
tor Vehicle Safety Standard 208 with which
the Advanced Airbag System in your vehicle
was certified), the front airbag on the passen ­
ger side may or may not deploy.
The
PASSENGER AIR BAG OFF light comes on
when the electronic control unit detects a to­
tal weight on the front passenger seat that re ­
quires the front airbag to be turned off. If the
PASSENGER AIR BAG OFF light does not
come on, the front airbag on the passenger
side has not been turned off by the control
unit and can deploy if the control unit senses
11-
•
•

-Always install rear-facing child safety
seats on the rear seat.
- If you must install a rearward facing
child safety seat on the front passenger
seat in exceptional circumstances and
the
PASSENGER AIR BAG OFF light does
not come on and stay on, immediately
install the rear-facing child safety seat in
a rear seating position and have the air­
bag system inspected immediately by
your Audi dealer.
_& WARNING
If, in exceptional circumstances, you must
install a forward-facing child restraint on
the front passenger's seat:
- Always make sure the forward-facing
seat has been designed and certified by its manufacturer for use on a front seat
with a passenger front and side airbag.
- Always follow the manufacturer's in­
structions provided with the child safety
seat or carrier.
- Always move the passenger seat into its
rearmost position in the seat's fore and
aft adjustment range, as far away from
the airbag as possible before installing
the child restraint. The backrest must be
adjusted to an upright position .
- Always make sure that the
PASSENGER
AIR BAG OFF
light comes on and stays
on all the time whenever the ignition is
switched on.
(D Tips
Always replace child restraints that were
installed in a vehicle during a crash. Dam­
age to a child restraint that is not visible
could cause it to fail in another collision
situation.
Advanced front airbag system and children
Your vehicle is equipped with a front "Ad­
vanced Airbag System" in compliance with United States Federal Motor Vehicle Safety
Child Safety 167
Standard (FMVSS) 208 as applicable at the
time your vehicle was manufactured.
The Advanced Airbag system in your vehicle
has been certified to meet the "low-risk" re­
quirements for 3- and 6-year old children on
the passenger side and small adults on the driver side. The low risk deployment criteria
are intended to reduce the risk of injury
through interaction with the airbag that can
occur, for example, by being too close to the
steering wheel and instrument panel when
the airbag inflates . In addition, the system
has been certified to comply with the "sup­
pression" requirements of the Safety Stand­
ard, to turn off the front airbag for infants up
to 12 months who are restrained on the front
passenger seat in child restraints that are list­
ed in the Standard.
Even though your vehicle is equipped with an
Advanced Airbag system, all children, espe­ cially those 12 years and younger, should al­
ways ride in the back seat properly restrained
for their age and size. The airbag on the pas­
senger side makes the front seat a potentially dangerous place for a child to ride . The front
seat is not the safest place for a child in a for­
ward-facing child safety seat. It can be a very
dangerous place for an infant or a larger child
in a rearward-facing seat .
Advanced Airbags and the weight­
sensing mat in the front seat
The Advanced Airbag System in your vehicle
detects the presence of an infant or child in a
child restraint on the front passenger seat us­
ing the weight -sensing mat in the seat cush­
ion and the sensor below the safety belt latch
on the front passenger seat that measures the
tension on the safety belt.
The weight -sensing mat measures total
weight of the child and the child safety seat
and a child blanket on the front passenger seat. The weight on the front passenger seat
is related to the design of the child restraint
and its "footprint", the size and shape of the
bottom of the child restraint as it sits on the ..,.
•
•

192 Intelligent technology
be advisable to mount winter tires (or all-sea­
son ti res) for improved driveability and brak­
ing: these t ires must be mounted on
all four
w heels .
See also c> page 250, Winter tires.
Snow chains
Where snow cha ins are mandatory on certa in
roads, this normally a lso applies to vehicles
with A ll Wheel Driver=:>
page 251, Snow
chains.
Replacing wheels /t ire s
Vehicles w it h All Wheel Dr ive must always
have tires of the same size . Also avoid tires
with different tread depths. For details see
page
c> page 246, New tires and replacing
tires and wheels.
Off-Road driv ing?
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 refe r to
i=>page 195.
A WARNING
Always adjust your driving to road and traf­
fic condit ions. Do not let the extra safety
afforded by All Whee l Drive tempt you into
taking extra risks.
-Although the All Whee l Drive is very ef­
fective, a lways remember that b raking
capacity is limited by t ire traction. You
should the refore not dr ive at excessive
speeds on icy or slippery road su rf a ces.
- On wet road su rfaces, be careful not to
dr ive t oo fast becau se t he front wheels
co uld beg in to s lide on top of the wa ter
(aquaplaning) .
If this should occ ur, you
wi ll have no warning from a sudden in­
crease in engine speed as with a front­
wheel drive vehicle. A lways drive at
speeds wh ic h are suited 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 conventiona l energy system
is not driven for a long per iod of t ime, t he bat­
te ry is discharged by idling current consume rs
(e.g. immobili ze r). In certa in circumstan ces it
ca n res ult in the re be ing insufficien t energy
available to start the eng ine.
Intelligent energy management in your vehi­
cl e ha ndles the dist rib ution o f electr ica l ene r­
gy. Start ing abili ty is m arkedly improved and
the life of the battery is extended .
Bas ica lly, energy management consists of
batt ery diagnosis , idling current manage­
ment
and dynamic energy management .
Battery diagnosis
Battery diagnosis continuously determines
the state of the batte ry. Sensors determine
batte ry voltage, battery cu rr e nt and battery
tempe ratu re. This de termines the cur ren t
state o f cha rge and t he power o f th e battery.
Idling current management
Idli ng current management reduces energy
consumpt ion while the vehicle is standing.
With the ig nition sw itched off, it controls the
energy supp ly to the variou s ele ctri ca l compo ­
nen ts. Da ta from ba ttery d iagnos is is co nsid­
ered.
Depend ing on the batte ry's state of cha rge,
i ndivid ual con sume rs a re g radually turned off
to prevent excessive discharge o f the battery
and th us main tain starting capabi lity.
Dynamic energy management
While the vehicle is being d riven, dynamic en­
ergy ma nagement distr ib utes the energy ge n­
era ted a ccord ing to t he needs of the individ u-
al components.
It r egula tes consumption, so
t h at more e lectrical energy is not being used ..,.

236 Tires and wheels
-Never mount used tires on yo ur 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.
Glossary of tire and loading terminology
Accessory weight
means the comb ined weight (in excess of
those standard items which may be rep laced)
of automatic transmission, power steering, power brakes, power windows, power seats,
radio, and heater, to the extent that these
items are availab le as factory -installed equip ­
ment (whether installed or not) .
Aspect ratio
means the ratio of the he ight to the w idth of
the tire in percent. Numbers of 55 or lower in­
dicate a low sidewall for improved steering re­
sponse and better overall handling on dry
pavement.
Bead
means the part of the tire that is made of
steel wires, wrapped o r reinforced by ply cords
and that is shaped to fit the r im.
Bead separation
means a breakdown of the bond between
components in the bead.
Cord
means the strands forming the plies in the
tire.
Cold tire inflation pressure
means the tire pressure recommended by the
vehicle manufacturer for a tire of a designated size that has not been driven for more than a
couple of miles (kilometers) at low speeds in
the three hour period before the tire pressure
is measured or adjusted. -
If you notice unusual vibration or if the
veh icle pulls to one side when driv ing, a l­
ways stop as soon as it is safe to do so and check the wheels and tires for dam­
age.
Curb weight
means the weight of a motor vehicle w ith
standard equipment including the maximum
capacity of fuel, oil, and coolant, air condi­
tioning and additional weight of optiona l
equipment.
Extra load tire
means a t ire design to operate at h igher loads
and at higher inflation pressures than the cor­
responding standard tire. Extra load tires may
be identified as "XL", "xl", "EXTRA LOAD", or
"R F" on the sidewall .
Gross Axle Weight Rating ( "GAWR ")
means the load-carrying capacity of a s ingle
axle system, measured at the tire-ground in­
terfaces .
Gross Vehicle Weight Rating ("GVWR")
means the maximum total loaded weight of
the vehicle.
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 given inflation pressure. Yo u
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 maxi­
mum permissib le 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 pressu re."
Normal occupant weight
means 150 lbs. (68 k ilograms) 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 overall diameter of an inflated new
tire.
Overall width
means the linear distance between the exteri­
ors of the sidewalls of an inflated tire, includ­
ing e levations due to labeling, decorations, or
protective bands or ribs.
Ply
means a layer of rubber-coated para llel cords.
Production options weight
means the comb ined weight of those installed
regular production options weighing 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, r ide leve lers, roof rack,
heavy duty battery, and specia l trim .
Radial ply tire
means a pneumatic t ire in which the p ly cords
that extend to the beads are laid at substan­
tially 90 degrees to the centerline of the
tread.
Tires and wheels 237
Recommended inflation pressure
see~
page 236, Cold tire inflation pressure.
Reinforced tire
means a t ire design to operate at higher loads
and at higher inflation pressures than the cor­
responding standard tire. Reinforced tires
may be identified as "XL ", "x l", "E XTRA LOAD",
o r "R F" on the sidewall.
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 d iameter of the bead seat. If
you change your wheel s ize, you w ill have to
purchase new tires to match the new r im di­
ameter.
Rim size designation
means r im diameter and width.
Rim width
means nom inal distance between rim fla nges.
Sidewall
means that portion of a tire between the
tread and bead.
Speed rating (letter code)
means the speed at which a tire is designed to
be driven for extended periods of time. The
ratings range from 93 mph (150 km/h) to
186 mph (298 km/h)
~ page 247 . You may
not find this information on all tires because
it is not requ ired by law.
The speed rating letter code, where applica­
ble, is molded on the tire sidewall and indi­
cates the max imum pe rm issib le road speeds
~ .&. in Winter tires on page 251.
Tire pressure monitoring system*
means a system that detects when one or
more of a veh icle's tires are underinflated and
illuminates a low tire pressure warning tell­
tale.
•
•

Tires and wheels 239
Cold tire inflation pressure
Tire pressure affects the overall handling, performance and safety of a vehicle .
Fig . 183 Tir e pr essur e labe l: located on drive r's s ide B ·
p ill ar
Tire pressu re genera lly refers to the amount
of air in a t ire tha t it needs it to do its job and
safely carry the combined load of the entire
vehicle and its contents . Tire pressure is
measured in kilopasca ls (kPa), the i nterna­
tional measuring unit and in pounds pe r
square inc h (PSI). Tire pressure is based in
pa rt o n the vehicle's desig n an d load limit­
the greatest amount of weight that the vehi­
cle can carry safe ly and the ti re size . The prop ­
er tire pressure is freq uent ly referred to as the
"recommended cold tire inf lation pressure ."
Air in the tires expands when the tire heats up
because of interna l frict io n when it flexes in
use . The ti re p ressu re is higher when the tire
has warmed up than when it is "cold ." It is the
i nflat io n pressure i n a "cold" tire that counts.
Therefo re, you s ho ul d never let air ou t of a
warm tire to match " cold tire infla tion p res­
sure" recommendations . The tires wo uld then
be underinf lated a nd could fail suddenly.
M ain taining proper t ire press ure is one of the
most impor tan t thi ngs you c an do to he lp
avoid sudden tire failure. Underinfla ted tires
are a major cause of s udden tire failure . Keep­
ing tires at the r ight pressure is also impor­
tant for safe and responsive vehicle handling,
traction, b rak ing and load carrying .
Tire pres­
sures are part icularly important wh en th e
vehicle is being driven at higher speeds , and
then especially when h eavily loaded even
within the permi ssible load -carrying capaci­
tie s approved for your vehi cle.
~
"' ~
,.------------------- ~
•(=~: I := I ~ I )§ :ll
,.,,. ........................ ...., .... ~----.... _ ... t.._.. .... _..,.. .... ......,... .. ~--......... ·- ..
-KPA. . PSI
- KPA. . PSI
- KPA. . PSI
Fig. 1 84 Tir e pressu re labe l
The recommended tire pressures for your Audi
depe nd on the kind of tires on your ve hicle
and t he number of passe ngers and/or amount
of luggage you w ill be t ransporting .
The tire pressure label is located on the driv­
er's side 8-pillar . The tire pressure labe l lists
the recommended cold t ire inflat io n pressures
for the veh icle at its maximum capac ity
weight and tires that we re o n your veh icle at
t h e time it was manufactu red.
If you wish to improve comfort when op erat­
ing the ve hicle at normal load (up to 2* /3
occupant s), you can adju st tire pres sures to
those specified for normal vehicle lo ad. Be­
fore operating the vehicle at maximum load ,
you must increase the tire pre ssure s to tho se
speci fied for maximum vehicle load
¢ .&.
Bear in mind that the tire pressure mon itor ing
system* can on ly mon itor the tire p ress ures
yo u have sto red. The sys tem does not recog ­
nize the load condition of your veh icle.
T he effectiveness of the t ire p ress ure monitor­
ing system * w ill be impa ired i f you s to re no r­
m al load pressures but t hen opera te the veh i­
cle a t its maximum load
¢ .& .
See the ill ustration 9 fig. 183 fo r the lo cat ion
of the label o n driver's s ide B-pillar (color of
the actu al label a nd exact lo cat ion on the ve­
hicle will vary s light ly).
Note t hat the follow ing table is accu rate at
the time of going to press and is s ubject to

240 Tires and wheels
change. In the event of discrepancies, the tire
pressure labe l is located on the driver's side B­
p ill ar a lways takes precedence.
The table below lis ts the recommended cold
tire inflation pressures for the Audi model covered
by your Owner's Literature at the vehi ­
cle's capacity weight and the tire sizes instal­
l ed on the respective models as orig inal
equipment, or as a factory option.
Tire pressure
Engine Tire designation normal load condition full load condition
fronta> reara>
front rear
AS 4.2 Ii-235/55 Rla 104H XL all
ter season
a -cylinder 255/45 R19 104H XL all
season
265/40 R20 104V XL
IA8 L4.2 Ii-235/55 Rla 104H XL all
ter season
a-cylinder 255/45 R19 104H XL all
season
6.3 li­
ter12-cyl­
inder 265
/40 R20 104V XL
265/40 R20 104V
255/45 R19 104H all sea-
son PSI
35
35
33
35
35
35
36
kPA
240
240
230
240
240
240
250
PSI
32
32
30
32
32
32
32
kPA
220
220
210
220
220
220
220
PSI kPA
36
250
36 250
33 230
36 250
36 250
36 250
39 270
PSI
38
38
35
38
38
35
38
kPA
260
260
240
260
260
240
240
260
I
I
I
XL= reinforced or extra load tire. It may also appear as xl, EXTRA LOAD, or RF on the tire side­
wall.
a l nor mal load co nd it io n"'> page 238 .
The correct tire pressure for the spare wheel is
located on a label on the driver's side B-pillar.
Because technical changes may be made to
vehicle equipment during the model year, a l­
ways compare the tire size designation on the
tire pressure label on your vehicle with the
tires on your vehicle. Make sure that the tire
size information on the veh icle label is the
same as the size of the tires on the vehicle.
This is especially important if the vehicle be­
l ongs to someone else or you bought the veh i­
cle with different rims/tires or you bought the
vehicle as a previously owned vehicle .
Remember, your safety and that of your pas­
sengers also depends on mak ing su re that
l oad limits are not exceeded. Vehicle load in­
cludes everybody and everything in and on the
vehicle . These load limits are technically refer- red to as the veh
icle's Gross Vehicle Weight
Rat ing ("GVWR"). The Gross Axle Weight Rat­
ing ("GAWR") is the maximum load that can
be applied at each of the vehicle's two axles .
The Gross Vehicle Weight Rating and the
Gross Axle Weight Rating are listed on the
safety compl iance sticke r label located on the
driver's side B-pillar. The tire pressu re labe l on
your Audi 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 tire pressure label
¢ fig. 183.
A WARNING
Overloading a vehicle can cause loss of ve­
hicle contro l, a crash or other accident, se­
rious personal injury, and even death.
- Carrying more we ight than your veh icle
was designed to carry will prevent the

Tire service life
The service life of tires depends on a lot of
different things including proper installation
and balancing, correct tire pressure and driv­
ing style.
F ig. 185 Tire tread: tread wea r ind ica tors (TWI)
f r-------~
{ \ .___ _____ ___,,
Fi g. 186 Rotat ing t ires fo r m ore even wea r
Tread Wear Indicator (TWI)
The origina l tires on your veh icle have
1/16 in ch (1.6 mm) high "wear ind icators"
c::> fig . 185 run ning across the tread. Depend ­
ing on the make, there will be six to eight of
them evenly p laced around the t ire . Marks on
the t ire s idewall (for example "TWI" or other
symbols) indicate the positions of the tread
wear ind icators . Worn t ires must be replaced.
Different fig ures may apply in other countries
c::> & .
Tir e pressure
Incorrect tire pressure causes premat ure wear
and can cause sudden tire blow-out . For th is
reason, tire pressure must be checked at least
once a month
c::> page 241.
Dri ving sty le
Driving fast around curves , heavy acceleration
and hard braking increase tire wear. Tires and wheels 245
Rotating tires for more even wear
For all four tires on your ve
hicl e to have the
same service life, we recommend that the
front and rear tires are rotated according to
the tire manufacturer 's suggested tire rota­
tion inte rvals. Please remember the follow ­
ing :
- Tire rotation intervals may differ from the
veh icle service inte rva ls o utlined 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 manufactu rer 's suggested
tire rotation intervals .
- Vehicles w ith front-wheel dr ive exper ience
more tread wear on the front wheels com­
pared to all -wheel d rive (quattro ®).
- Please rotate tires as shown
c::> fig. 186.
-Extra care must be taken when rotat ing di-
rection-specific tires
c::> page 264 .
Wheel balancing
The wheels on new veh icles are balanced .
However, various situations during everyday
driving can cause them to become unba l­
anced, resulting in vibrat ions you can usually
feel through the steer ing wheel.
Unbalanced wheels must be rebalanced to
avoid excessive wear on steering, s uspension
and t ires. A whee l must also be reba lanced
when a new tire is insta lled.
Inco rrect wheel alignment
Incorrect wheel alignment can cause exces­
sive tire wear, impair ing the safety of the vehi­
cle . If tires show excessive wear, have the
whee l alignment checked by an authori zed
Audi dealer or qualified workshop.
All Wh eel Driv e
Vehicles wi th quattro ® mus t always have tires
of the same size, construction and tread type. For details see
c::> page 191.