wheel size AUDI A5 2008 8T / 1.G Owners Manual

Page 247 of 313

Wheels and tyres245
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Tread wear indicators
The tread wear indicators show the condition of the tyre
treads.The original tyres on your vehicle have 1.6 mm high “tread wear
indicators” ⇒fig. 232 running across the tread. Depending on the
make, there will be 6 to 8 of them spaced at equal distances around
the tyre. Markings on the tyre sidewall (for instance the letters “TWI”
or a triangle) indicate the positions of the tread wear indicators.
The minimum tread depth required by law in Germany is 1.6 mm
(measured in the tread grooves next to the tread wear indicators).
Other specifications may apply in export countries.
WARNING
To avoid putting safety at risk, the tyres must be replaced at the
latest when the tread is worn down to the tread wear indicators.•
Especially in difficult driving conditions such as wet or icy
roads, it is important that the tyres have sufficient tread depth.
The tread depth should same on the tyres of both the front and the
rear axles.

The decrease in driving safety due to insufficient tread depth is
particularly evident in vehicle handling, when there is a risk of aquaplaning in deep puddles of water and when driving through
corners. Braking is also adversely affected.

The speed has to be adapted accordingly, otherwise there is a
risk of losing control over the vehicle.
Changing wheels roundTo ensure that the wear is equal on all tyres the wheels should be
changed round from time to time according to the system
⇒fig. 233. All the tyres will then last for about the same time.Replacing wheels and tyres
It is important to use the correct wheels and tyres when
replacement is necessary.– All four wheels must be fitted with tyres of the same type,
size (rolling circumference) and preferably the same
tread pattern.
– If possible, tyres should be replaced at least in pairs and
not individually (i.e. both front tyres or both rear tyres
together).
Fig. 232 Tyre tread:
Tr e a d w e a r i n d i c a t o r s
WARNING (continued)
Fig. 233 Changing
wheels round
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Wheels and tyres 246
– Never use tyres whose actual size exceeds the dimen-
sions of the factory-approved makes of tyre.
– If you wish to fit the vehicle with non-standard rims or
tyres, it is advisable to consult an Audi dealer before
purchasing them.The tyres and wheel rims are an essential part of the vehicle's
design. The tyres and rims approved by Audi are specially matched
to the characteristics of the vehicle and make a major contribution
to good roadholding and safe handling ⇒.
The sizes of the rims and tyres approved for your vehicle are listed
in the vehicle's documents (e.g. EC Certificate of Conformity or COC
document
5)). The vehicle documents vary depending on the
country of residence.
Understanding the tyre designations makes it easier to choose the
correct tyres. For example, radial ply tyres have the following tyre
designations marked on the sidewall:
225 / 50 R 17 94 Y
This contains the following information:
The manufacturing date is also indicated on the tyre sidewall
(possibly only on the inner side of the wheel):
DOT ... 1006...means, for example, that the tyre was produced in the 10th week of
2006.
Please note that with some types of tyres, the actual tyre size can
differ from the nominal size marked on the tyre (for instance 225/50
R 17 94 Y), and there may be significant differences in the contours
of the tyres, even though the tyres are marked with the same
nominal size designation. When replacing the tyres, it is therefore
important to make sure that the actual size of the new tyres does
not exceed the dimensions of the factory-approved makes of tyre.
Failure to observe this requirement can affect the clearance needed
for the tyres. This could result in contact between the tyres and
suspension components or bodywork. The brake lines could also be
damaged and the vehicle's safety could be severely impaired ⇒.
When using tyres with the maximum permitted nominal dimen-
sions, this can also void the vehicle's registration.
If you use tyres that are approved by Audi you can be sure that the
actual tyre dimensions will be correct for your vehicle. If you decide
to fit a different type of tyre, you must obtain the appropriate manu-
facturer's certificate from the tyre retailer to confirm that the tyres
are suitable for your vehicle. Keep this certificate in a safe place.
Your local Audi dealer will be able to advise you on which tyres may
be fitted to your vehicle.
On vehicles with four-wheel drive, all four tyres must always be
fitted with tyres of the same type, make and tread pattern, as other-
wise the driveline can be damaged by continuous variations in the
wheel speeds. For the same reason, only use a spare wheel* with
the same tyre dimensions as the normal road wheels.
It the spare tyre* is not the same type as the tyres fitted on the car
(for example if the car has winter tyres or wide-section tyres) you
should only use the spare tyre if a puncture occurs, and then only
for a short period of time. In this case, please drive with extra care.
Refit the normal road wheel as soon as possible.
It is best to have all servicing of wheels and tyres performed by a
qualified workshop. They have the necessary special tools and
5)COC = certificate of conformity
225
Tyre width in mm
50
Height/width ratio in %
R
Tyre construction: Radial
17
Rim diameter in inches
94
Load rating code
Y
Speed rating code letter
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Wheels and tyres247
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data replacement parts, trained personnel and facilities for disposing of
the old tyres.
WARNING

It is very important to ensure that the tyres you have chosen
have adequate clearance. When selecting replacement tyres, do
not rely entirely on the nominal tyre size marked on the tyre; with
some makes of tyre the effective tyre size can differ significantly
from the nominal dimensions, even though the tyres have the
same size designation. Inadequate tyre clearance can result in
damage to the tyres or the vehicle, causing a serious safety risk. It
may also invalidate the vehicle's type approval for use on public
roads.

Please ask your Audi dealer or qualified workshop whether run
flat tyres can be used on your vehicle. Unauthorised use of these
tyres can invalidate the vehicle's type approval for use on public
roads. Furthermore, this could cause damage to your vehicle and
possibly also result in an accident.

Avoid running the car on tyres that are more than 6 years old.
If you have no alternative, you should drive slowly and with extra
care at all times.For the sake of the environment
Old tyres must be disposed of according to the laws in the country
concerned.
Note

Never mount used tyres if you are not sure of their previous
history.

For technical reasons it is not normally possible to use wheel
rims from other vehicles. In some cases this also applies to rims
from other vehicles of the same model.
Wheel bolts
The wheel bolts are designed to suit the rims on your car.The wheel bolts are matched to the rims. When installing different
wheels (for instance wheels with winter tyres) it is important to use
the correct wheel bolts with the right length and correctly shaped
bolt heads. This is essential for the secure fit of the wheels and for
the proper function of the brake system.
Audi dealers have full information on the technical requirements
when installing or changing tyres, rims or wheel trims.
The wheel bolts should be clean and turn easily.
A special adapter is required to turn the anti-theft wheel bolts*
⇒page 264.Winter tyres
Winter tyres will significantly improve the car's handling
in winter road conditions.–Use only radial ply winter tyres.
– Winter tyres must be fitted on all four wheels.
– Only use winter tyres of the correct type approved for
your vehicle.
– Please note that the maximum permissible speed for
winter tyres may be lower than for summer tyres.
– Also note that winter tyres are no longer effective when
the tread is worn down.
– After fitting the wheels you must always check the tyre
pressures. The correct tyre pressures are listed on the
sticker on the end face of the driver's door.
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Wheels and tyres 248In winter road conditions winter tyres will considerably improve the
car's handling. Due to their type of construction (width, rubber
compound, tread pattern), summer tyres give less grip on ice and
snow. This applies particularly to vehicles equipped with wide
section tyres or high speed tyres (code letters H, V or Y on the side-
wall).
Only use winter tyres of the correct type approved for your vehicle.
The sizes of the winter tyres approved for your vehicle are listed in
the vehicle's documents (e.g. EC Certificate of Conformity or COC
document
6)). The vehicle documents vary depending on the
country of residence. Also refer to ⇒page 245.
Winter tyres are no longer fully effective when the tread is worn
down to a depth of 4 mm.
The performance of winter tyres is also severely impaired by ageing,
even if the tread is still much deeper than 4 mm.
Winter tyres are subject to the following maximum speed limits
according to speed rating code letter: ⇒
In Germany vehicles capable of exceeding these speeds must have
an appropriate sticker attached so it is visible to the driver. Suitable
stickers are available from Audi dealers and specialist retailers.
Please note regulations to this effect in your country.“All-weather” tyres can also be used instead of winter tyres.
Using winter tyres with V-rating
Please note that the generally applicable 240 km/h speed rating for
winter tyres with the letter "V" is subject to technical restrictions;
the maximum permissible speed for your vehicle may be signifi-
cantly lower. The maximum speed limit for tyres with a V-rating
depends directly on the maximum axle weights for your car and on
the listed weight rating of the tyres being used.
It is best to contact an Audi dealer to check the maximum speed
which is permissible for the V-rated tyres fitted on your car on the
basis of this information.
WARNING
Exceeding the maximum speed permitted for the winter tyres
fitted on your car can cause tyre failure, resulting in a loss of
control of the vehicle – risk of accident.
For the sake of the environment
Summer tyres should be fitted again as soon as possible; they give
better handling on roads which are free of snow and ice. Summer
tyres produce less rolling noise, do not wear down as quickly and,
most importantly, reduce fuel consumption.Snow chains
Snow chains will improve the vehicle's handling on snow-
covered roads.– Snow chains can be used on the front wheels only.
– Keep your speed below 50 km/h.Snow chains will improve braking ability as well as traction in winter
conditions.
6)COC = certificate of conformitySpeed rating code letter
⇒page 245
Maximum speed limit
Q
160 km/h
S
180 km/h
T
190 km/h
H
210 km/h
V
240 km/h
(note restrictions)
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Wheels and tyres249
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data For technical reasons snow chains may only be used on tyres with
certain wheel rim/tyre combinations.
Only use snow chains with fine-pitch links. The links must not
protrude more than 13.5 mm from the tyres (including tensioner).
Remove the chains when roads are free of snow. Otherwise they will
impair handling, damage the tyres and wear out very quickly.
Four-wheel drive: where snow chains are compulsory on certain
roads, this normally also applies to cars with four-wheel drive. Snow
chains may only be fitted to the front wheels (also on vehicles with
four-wheel drive).
Rim size
Rim offset
Ty r e s i z e
7.5Jx17
28 mm
225/50
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Self-help257
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data How to use the compact temporary spare wheel
Should you ever have a punctured tyre, the compact temporary
spare wheel is only intended for temporary use until you can reach
a workshop. The standard-size road wheel should be refitted as
soon as possible.
Please note the following restrictions when using the compact
temporary spare wheel. The compact temporary spare wheel is
designed specifically for this model. For this reason, do not use a
temporary spare from a different type of vehicle.
Snow chains
For technical reasons, snow chains must not be used on the
compact temporary spare wheel.
If you should have a puncture on one of the front wheels when using
snow chains, fit the compact temporary spare in place of one of the
rear wheels. You can then attach the snow chains to the wheel taken
from the rear and use this wheel to replace the punctured front
wheel.
WARNING

The tyre pressures must be checked and corrected as soon as
possible. The tyre pressure of the compact temporary spare wheel
must be 4.2 bar – an incorrectly inflated tyre can cause an acci-
dent.

Do not drive faster than 80 km/h - higher speeds can cause an
accident.

Avoid heavy acceleration, hard braking and fast cornering – risk
of accident.

Never use two or more compact spare tyres at the same time –
risk of accident.

No other type of tyre (normal summer or winter tyres) may be
fitted on the compact temporary spare wheel.
Ty r e r e p a i r sGeneral information and safety notes
Repaired tyres are only suitable for temporary use.Your vehicle is equipped with a tyre repair kit: the Tyre Mobility
System (TMS).
In the event of a puncture you will find the TMS, which consists of a
sealing compound and an electric compressor, located under the
floor panel in the luggage compartment.
The TMS will reliably seal tyres damaged by foreign bodies,
provided that the cuts or punctures are no larger than approx. 4 mm
in diameter.
It is not necessary to remove the foreign body from the tyre.
The sealing compound must not be used:•
on cuts and punctures larger than 4 mm ⇒fig. 239

if the wheel rim has been damaged

if you have been driving with very low pressure or a completely
flat tyre .
How to use the TMS is described in the section Repairing a tyre
⇒page 258 and in the instructions supplied with the tyre sealant
can.
Fig. 239 The Tyre
Mobility System is NOT
suitable for repairing
this type of damage to
tyres.
A1
A2
A3
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