2021 AUDI Q8 service

4M8012721BF
Wheels


absolutely necessary and drive
carefully when doing so.
—Do not use run-flat tires on
your vehicle. Using them when
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
rr)
+
x xz + a

Fig. 166 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.

D Obey any applicable regulations in the
country where the vehicle is being oper-
ated.
—Driving quickly through curves,
rapid acceleration, and heavy
braking increase tire wear.
—Have an authorized Audi dealer
or authorized Audi Service Facili-
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. 166. 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.
265

Wheels

Tire rotation
Rotating the tires regularly is rec-
ommended to ensure the tires
wear evenly. To rotate the tires,
install the tires from the rear axle
on the front axle and vice versa.
This will allow the tires to have
approximately the same length of
service life.
For unidirectional tires, make sure
the tires are installed according to
the running direction indicated on
the tire sidewall > page 291.
Hidden damage
Damage to tires and rims can of-
ten occur in locations that are hid-
den. Unusual vibrations in the ve-
hicle or pulling to one side may
indicate that there is tire damage.
Reduce your speed immediately.
Check the tires for damage. If no
damage is visible from the out-
side, drive slowly and carefully to
the nearest authorized Audi deal-
er or authorized Audi Service Fa-
cility to have the vehicle inspect-
ed.


Z\ WARNING
Tread that has worn too low or
uneven tread depths on the
tires can reduce driving safety.

266

This can increase the risk of an
accident because it has a nega-
tive effect on handling, driving
through curves, and braking,
and because it increases the
risk of hydroplaning when driv-
ing through deep puddles.
AT -m as T


B41L-1383

Fig. 167 Driver's side B-pillar: tire pres-
sure label


B8K-1151 Pee
‘SEATING CAPACITY TOTAL FRONT R NOMBRE DE ‘OTAL /ANT ARRIERE
eed 9 oF pmb , a;
COLD TIRE PRESSURE
PRESSION DES PNEUS A FROID
a KPA, HM PSI
a KPA, Mi PSI
Ga KPA, MM PSI
TIRE SIZE
PNEU _| DIMENSIONS
FRONT
AVANT
REAR
i_|
ARRERE |
‘SPARE a




DE SECOURS


Fig. 168 Tire pressure label
The correct tire pressure for tires
installed at the factory is listed on
a label. The label is located on the
B-pillar > fig. 167, > fig. 168.
Use the tire pressure specified for
a normal vehicle load when the
vehicle is partially loaded > table »

Wheels


ZA\ WARNING
Wheel bolts that are tightened or repaired in-
correctly can become loose and result in loss
of vehicle control, which increases the risk of
an accident. For the correct tightening specifi-
cation, see > page 291, Finishing.
— Always keep the wheel bolts and the threads
in the wheel hub clean and free of grease.
— Only use wheel bolts that fit the rim.
— Always have damaged rims repaired by an
authorized Audi dealer or authorized Audi
Service Facility. Never repair or disassemble
rims yourself, because this increases the risk
of an accident.
Loose wheel warning
Applies to: vehicles with loose wheel warning

Within the limits of the system, the loose wheel
warning in the instrument cluster warns you if
one or more wheels are loose.
Using the ABS sensors, the loose wheel warning
system compares the vibration characteristics of
the individual tires. If one or more wheels are
loose, it will be indicated in the instrument clus-
ter display with the & indicator light and a mes-
sage. If only one wheel is affected, the location
of that wheel will be indicated.
Messages
fi Wheel bolts loose. Please safely stop the ve-
hicle and check all wheel bolts!
Loose wheel warning for at least one wheel > A\.
Check the wheel bolts on all wheels with the
wheel wrench (vehicle tool kit). Have the tighten-
ing specification checked as soon as possible with
a torque wrench. Drive carefully until then. For
the correct tightening specification, see
=> page 291, Finishing.
fl Wheel assessment active. Please continue
driving carefully
After this message appears and you have checked
the wheel bolts, the assessment phase begins
when the vehicle is in motion. This may take sev-
eral minutes.
272
fi Loose wheel warning: malfunction! See
owner's manual
There is a system malfunction. Drive immediately
to an authorized Audi dealer or authorized Audi
Service Facility to have the malfunction repaired.

Z\ WARNING
Wheel bolts that are tightened incorrectly can
become loose and result in loss of vehicle con-
trol, which increases the risk of an accident.
— If a message appears, reduce your speed im-
mediately and avoid any hard steering or
braking maneuvers. Stop as soon as possible
and check the wheel bolts.
— Check your wheels for damage. Have the
damaged wheels checked and/or replaced
immediately by an authorized Audi dealer or
authorized Audi Service Facility.
— Under certain conditions (such as a sporty
driving style, winter conditions, or unpaved
roads), the message may be delayed.
— The driver is responsible for ensuring that
the wheels are attached correctly.
(i) Tips
— The loose wheel warning system can also
stop working when there is an ESC malfunc-
tion.

— Using snow chains may result in a system
malfunction.
Winter tires significantly improve the vehicle's
handling when driving in winter conditions. Be-
cause of their construction (width, compound,
tread pattern), summer tires provide less traction
on ice and snow.
> Use winter tires on all four wheels.
> Only use winter tires that are approved for your
vehicle.
> Please note that the maximum permitted
speed may be lower with winter tires > A\ in
General information on page 256. An author-
ized Audi dealer or authorized Audi Service Fa-
cility can inform you about the maximum per-
mitted speed for your tires.

4M8012721BF
Wheels

> Check the tire pressure after installing wheels
=> page 266.
The effectiveness of winter tires is reduced great-
ly when the tread is worn down to a depth of
0.16 in (4 mm). The characteristics of winter tires
also decrease greatly as the tire ages, regardless
of the remaining tread.
@) For the sake of the environment
Reinstall summer tires at the appropriate
time, because they provide better handling
when roads are free of snow and ice. Summer
tires cause less road noise, tire wear, and fuel
consumption.
@) Tips
You can also use all season tires instead of
winter tires. Please note that in some coun-
tries where winter tires are required, only win-
ter tires with the 4 symbol may be permit-
ted.
Tea
Snow chains improve both driving and braking in
winter road conditions.
> Only install snow chains on the rear wheels.
> Check and correct the seating of the snow
chains after driving a few feet, if necessary. Fol-
low the instructions from the manufacturer.
> Note the maximum speed of 30 mph
(50 km/h). Observe the local regulations.
Use of snow chains is only permitted with certain
rim/tire combinations due to technical reasons.
Check with an authorized Audi dealer or author-
ized Audi Service Facility to see if you may use
snow chains.
Use fine-mesh snow chains. They must not add
more than 0.40 inch (10.5 mm) in height, includ-
ing the chain lock.
You must remove the snow chains on roads with-
out snow. Otherwise, you could impair driving
ability and damage the tires.

ZA\ WARNING
Using incorrect snow chains or installing snow
chains incorrectly can result in loss of vehicle
control, which increases the risk of an acci-
dent.
(@) Note
— Snow chains can damage the rims and
wheel covers* if the chains come into direct
contact with them. Remove the wheel cov-
ers* first. Use coated snow chains.

— Do not install and use snow chains if there is
a malfunction in the air suspension*, be-
cause the vehicle height will be very low. If
you drive with snow chains anyway, the
wheel housings and other vehicle compo-
nents can be severely damaged.
G@) Tips
When using snow chains, it may be advisable
to limit the ESC > page 116.
Low-profile tires
Applies to: vehicles with low-profile tires
Compared to other tire/rim combinations, low-
profile tires offer a wider tread surface and a
larger rim diameter with shorter tire sidewalls.
This results in an agile driving style. However, it
may reduce the level of comfort and increase
road noise when driving on roads in poor condi-
tion.
Low-profile tires can become damaged more
quickly than standard tires when driving over
large bumps, potholes, manhole covers, and
curbs. Therefore, it is particularly important to
maintain the correct tire pressure > page 266.
To reduce the risk of damage to the tires and
rims, drive very carefully on poor roads.
Check your wheels regularly every 2,000 mi
(3,000 km) for damage. For example, check for
bulges/cracks on the tires or deformations/cracks
on the rims.
After
a heavy impact or damage, have the tires
and rims inspected or replaced immediately by
273
>

Wheels

an authorized Audi dealer or authorized Audi
Service Facility.
Low-profile tires can wear out faster than stand-
ard tires.

item Me Clin meleCel lire)
— Tread wear
— Traction AAABC
— Temperature ABC
Quality grades can be found where applicable on
the tire side wall between tread shoulder and
maximum section width > page 257, fig. 165.
For example: Tread wear 200, Traction AA, Tem-
perature A.
All passenger car tires must conform to Federal
Safety Requirements in addition to these grades.
Tread wear
The tread wear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a specified gov-
ernment test course.
For example, a tire graded 150 would wear one
and one half (1 1/2) times as well on the govern-
ment course as a tire graded 100.
The relative performance of tires depends upon
the actual conditions of their use, however, and
may
depart significantly from the norm due to
variations in driving habits, service practices and
differences in road characteristics and climate.
Traction
The traction grades, from highest to lowest, are
AA, A, Band C. Those grades represent the tire's
ability to stop on wet pavement as measured un-
der controlled conditions on specified govern-
ment test surfaces of asphalt and concrete. A tire
marked C may have poor traction performance
oA.
Temperature
The temperature grades are A (the highest), B,
and C, representing the tire's resistance to the
generation of heat and its ability to dissipate
274
heat when tested under controlled conditions on
a specified indoor laboratory test wheel.
Sustained high temperature can cause the mate-
rial of the tire to degenerate and reduce tire life,
and excessive temperature can lead to sudden
tire failure > A\.
The grade C corresponds to a Level of perform-
ance which all passenger car tires must meet un-
der the Federal Motor Vehicle Safety Standard
No. 109. Grades B and A represent higher Levels
of performance on the laboratory test wheel than
the minimum required by law.

Z\ WARNING
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration, cor-
nering, hydroplaning or peak traction charac-
teristics.

ZX WARNING
The temperature grade for this tire is estab-
lished for a tire that is properly inflated and
not overloaded. Excessive speed, underinfla-
tion, or excessive loading, either separately or
in combination, can cause heat buildup and
possible tire failure.

ZA WARNING
Temperature grades apply to tires that are
properly inflated and not over or underinflat-
ed.

Tire pressure monitoring
system
(1) General notes
Each tire, including the spare (if provided),
should be checked monthly when cold and inflat-
ed to the inflation pressure recommended by the
vehicle manufacturer on the vehicle placard or
tire inflation pressure label. (If your vehicle has
tires of a different size than the size indicated on
the vehicle placard or tire inflation pressure la-
bel, you should determine the proper tire infla-
tion pressure for those tires).

Wheels

minute and then stays on, there is system mal-
function. Try to store the correct tire pressures
= page 276. Insome cases, you must drive for
several minutes after storing the pressures until
the indicator light turns off. If the indicator light
does turn off or turns on again after a short peri-
od of time, drive to an authorized Audi dealer or
authorized Audi Service Facility immediately to
have the malfunction corrected.

ZA\ WARNING
— If the tire pressure indicator appears in the
display, reduce your speed immediately and
avoid any hard steering or braking maneu-
vers. Stop as soon as possible and check the
tires and their pressure.
— The driver is responsible for maintaining the
correct tire pressure. You must check the
tire pressure regularly.
— Under certain conditions (such as a sporty
driving style, winter conditions, or unpaved
roads), the tire pressure monitoring system
indicator may be delayed.

(i) Tips
— The tire pressure monitoring system can al-
so stop working when there is an ESC mal-
function.
— Using snow chains may result in a system
malfunction.
— The tire pressure monitoring system in your
Audi was calibrated with “Audi Original
Tires” > page 263. Audi recommends using
these tires.
Storing tire pressures
Applies to: vehicles with Tire Pressure Monitoring System in-
dicator
If the tire pressure changes or a tire is replaced,
it must be confirmed in the MMI.
> Before storing the tire pressures, make sure the
tire pressures in all four tires meet the speci-
fied values and are adapted to the load
=> page 266.
> Switch the ignition on.
> Applies to MMI: Select on the home screen: VE-
HICLE > Settings & Service > Tire pressure
276
monitoring > Store tire pressure > Yes, store
now.
@) Tips
Do not store the tire pressures if snow chains
are installed.
Tire pressure monitoring
system
(1) General notes
Each tire, including the spare (if provided),
should be checked monthly when cold and inflat-
ed to the inflation pressure recommended by the
vehicle manufacturer on the vehicle placard or
tire inflation pressure label. (If your vehicle has
tires of a different size than the size indicated on
the vehicle placard or tire inflation pressure la-
bel, you should determine the proper tire infla-
tion pressure for those tires).
As an added safety feature, your vehicle has been
equipped with a tire pressure monitoring system
(TPMS) that illuminates a Low tire pressure tell-
tale when one or more of your tires is significant-
ly under-inflated. Accordingly, when the low tire
pressure telltale illuminates, you should stop and
check your tires as soon as possible, and inflate
them to the proper pressure. Driving ona signifi-
cantly under-inflated tire causes the tire to over-
heat and can lead to tire failure. Under-inflation
also reduces fuel efficiency and tire tread life,
and may affect the vehicle's handling and stop-
ping ability.
Please note that the TPMS is not a substitute for
proper tire maintenance, and it is the driver's re-
sponsibility to maintain correct tire pressure,
even if under-inflation has not reached the level
to trigger illumination of the TPMS low tire pres-
sure telltale.
Your vehicle has also been equipped with a TPMS
malfunction indicator to indicate when the sys-
tem is not operating properly. The TPMS mal-
function indicator is combined with the low tire
pressure telltale. When the system detects a
malfunction, the telltale will flash for approxi-
mately one minute and then remain continuously >

4M8012721BF
Wheels

illuminated. This sequence will continue upon
subsequent vehicle start-ups as long as the mal-
function exists.
When the malfunction indicator is illuminated,
the system may not be able to detect or signal
low tire pressure as intended. TPMS malfunctions
may occur for a variety of reasons, including the
installation of replacement or alternate tires or
wheels on the vehicle that prevent the TPMS
from functioning properly. Always check the
TPMS malfunction telltale after replacing one or
more tires or wheels on your vehicle to ensure
that the replacement or alternate tires and
wheels allow the TPMS to continue to function
properly.
General information
Applies to: vehicles with tire pressure monitoring system
The tire pressure monitoring system monitors
the pressure in the four tires when driving.
The system uses sensors that measure the tem-
perature and pressure in the tires. The data is
sent from these sensors to the control module by
radio frequency.
The tire pressure monitoring system shows the
current pressures and temperatures of the tires
in the MMI while driving > page 277. It also
compares the current tire pressures with the stor-
ed tire pressures and gives a warning in the driver
information system if the tire pressure is differ-
ent from what is stored > page 278.
The system does not detect if the stored tire
pressures match the recommended tire pres-
sures. You must store the tire pressures again in
each of the following situations > page 278:
— Each time the tire pressures change, for exam-
ple when the load in the vehicle changes
— After replacing a tire
— If wheels with new wheel sensors are used

Z\ WARNING
— The tire pressure monitoring system assists
the driver in monitoring tire pressures. The
driver is responsible for having the tires in-
flated to the correct pressure.

— Do not change the tire pressure when the
temperature of the tire is extremely high.
This could result in serious damage to the
tire and even cause the tire to burst, increas-
ing the risk of an accident.
— A tire with low pressure flexes more. This
heats the tire up too much. This could cause
the tread to separate and even cause the tire
to burst, increasing the risk of an accident.
— The tire pressure monitoring system does
not warn about damage or defects in the
tire construction that could cause the tire to
burst, for example. Inspect your tires regu-
larly.
G) Tips
—If tires are replaced, the sensors and valves
do not need to be removed or replaced. Only
replace the valve stem and, if necessary, the
valve and the wheel electronics. If you have
questions, see an authorized Audi dealer or
authorized Audi Service Facility.
—An incorrect display or a malfunction in the
tire pressure monitoring system can occur
after using the tire mobility kit*. Have the
sensors replaced by an authorized Audi
dealer or authorized Audi Service Facility.
— The system complies with United States FCC
regulations and ISED regulations
=> page 311.
Displaying tire pressures and temperatures
Applies to: vehicles with tire pressure monitoring system


Requirement: you must be driving the vehicle.
> Applies to MMI: Select on the home screen: VE-
HICLE > Settings & Service > Tire pressure
monitoring > Display tire pressure.
The current tire pressures are shown in green,
yellow, or red numbers:
— Green: the current tire pressure and the speci-
fied tire pressure are approximately the same.
— Yellow: the current tire pressure is lower than
the specified tire pressure.
— Red: the current tire pressure is much lower
than the specified tire pressure.
277

Wheels

The specified tire pressure is the last tire pressure
that was stored > page 278.
Note that the tire pressure also depends on the
temperature of the tire. The tire pressure increas-
es as the engine becomes warmer while driving.

Z\ WARNING
Read and follow the important information
and notes > page 277.
@) Tips
The tire pressure or temperature is not dis-
played while the vehicle is stationary and in
adaptation mode. Dashes --.-- are shown in
place of the pressure and temperature.
OB iw sete ot
Applies to: vehicles with tire pressure monitoring system

If the @ indicator light turns on, the tire pres-
sure is too low compared to the specified pres-
sure. Check and store the tire pressure(s) the
next time it is possible > page 278.
® Flat tire! Safely stop vehicle. Please check all
tires and store pressures in MMI
If the indicator light turns on and the message
appears, the tire pressure has reached a critical
level compared to the specified pressure. Avoid
unnecessary steering and braking maneuvers.
Adapt your driving style to the situation. Stop as
soon as possible and check the tire(s). If it is pos-
sible to continue driving, see an authorized Audi
dealer or authorized Audi Service Facility immedi-
ately and have your tire(s) repaired or replaced.

Z\ WARNING
Read and follow the important information
and notes > page 277.

278
Storing new tire pressures
Applies to: vehicles with tire pressure monitoring system
The tire pressure specifications must be stored
correctly for the tire pressure monitoring system
to function reliably.
It is always necessary to store the tire pressures
when the tire pressures are modified, for exam-
ple due to a change in load or when new sensors
are installed.
> Before storing the tire pressures, make sure the
tire pressures of all four tires meet the speci-
fied values and are adapted to the load
=> page 266, fig. 168. Only correct and store
the pressure in tires whose temperature is ap-
proximately the same as the ambient tempera-
ture. If the temperature of the tire is higher
than the ambient air temperature, the tire
pressure must be increased approximately
3 PSI (0,2 bar) above the value on the sticker.
> Switch the ignition on.
> Applies to MMI: Select on the home screen: VE-
HICLE > Settings & Service > Tire pressure
monitoring > Store tire pressure > Yes, store
now.
> If the changed tire pressures are not displayed
on the MMI, drive the vehicle for approximately
10 minutes so that the sensor signal from the
wheels is received again.
During this adaptation phase, --.-- is displayed
for the pressure and temperature and the tire
pressure monitoring system is only partially
available. It only provides a warning if one or
more tire pressures is below the minimum per-
mitted specified pressure.
@ Tire pressure: wheel change detected. Please
check all tires and store pressures in MMI
If the indicator light turns on and the message
appears, the system has detected that the loca-
tion of the sensors has changed due to a wheel
replacement, or new sensors have been installed.
Store the new tire pressures.

ZA WARNING
Read and follow the important information
and notes > page 277.