2015 AUDI A7 wheel torque

196 Intellig ent technolog y
distance detected to the veh icle a head is too
smal l.
Anti -slip regulation (ASR )
ASR reduces engine power when the drive
wheels begin to spin and adapts the force to
the road condit ions. This makes it eas ier to
start, accelerate and drive up hills.
Electronic differential lock (EDL )
The ED L brakes wheels that are spinn ing and
transfers the d rive power to the other wheels.
This f unct ion is not availab le at h igher speeds.
In extreme cases, EDL automat ically switches
off to help keep the brake on the braked whee l
from overheating. EDL w ill switch on aga in au­
tomatically when conditions have returned to norma l.
St eering recommendat ion
The ESC helps to stabilize the vehicle by
cha nging the steering to rque.
In vehicles with dynam ic steering*, ESC also
helps to stabilize the steering in critical s itua­
tions .
Select ive w heel to rque control
Selective wheel torque control is used when
driving on curves . The front wheel on the in­
side of the curve or both wheels on the inside
of the curve are braked selectively as needed.
This a llows more prec ise driving in curves. The
applicable system may not activate when d riv­
ing i n wet or snowy conditions.
.&_ WARNING
- T he ESC and its integrated systems can­
not overcome the limits posed by natural physical laws
. This is especially impor­
tant on slippery or wet roads. If the sys­ tems beg in acting to stabilize your vehi­
cle, you should immediately change your
speed to match the road and traffic con­
d itions . Do not let the increased safety
p rovided by these systems tempt you to
take risks. Do ing so will increase the ri sk
of a loss of veh icle cont ro l, collision and
serio us personal inj uries.
- Always adapt your speed to road, traffic
and weather conditions . The risk of los ­
ing control of the vehicle increases when
driving too fast , especially through
curves and on slippery or wet roads, and
when dr iv ing too close to vehicles up
ahead . The ESC and its integrated sys­
tems cannot a lways prevent collisions -
there is still a risk of acc idents!
- Always accelerate with special care on
even, smooth su rfaces such as those that
are wet or covered with ice and snow .
The drive wheels can spin even w ith
these assistance systems that c annot al­
ways he lp to red uce the risk of loss of ve­
h icle control.
(D Tips
- ABS and ASR only wo rk correctly when
all four wheels are equipped wi th iden ti­
cal tires. D ifferen t tire sizes can lead to a
reduction in engine power.
- Yo u may hear noises when the systems
descr ibed are workin g.
-If the ind icator light DJ or Ea (USA
mode ls)/ lCO j there may be a malfunction~
page 19,
<=>page 19.

200 Intelligent technology
nearest Audi dealer or qualified work­
shop.
- Never let the vehicle ro ll to a stop with
the engine shut off.
- If the brake booster is not working, the
brake pedal must be pressed considera­
bly harder to make up for the lack of
booster assistance.
Electromechanical
power assist, dynamic
steering
The electromechanical power assist helps the
driver when steering.
Power steering adapts electronically based on
the vehicle speed.
Indicator lights and messages
• Steering defective! Stop the vehicle
If this indicator light turns on and stays on
and this message appears, the power steering
may have failed.
Do
not continue driving. See your authorized
Audi dealer or other qualified repair facility
for assistance.
l>:r-ij Steering: System fault You can continue
driving
If the indicator light turns on and the mes­
sage appears, the steering may be more diffi­
cult to move or more sensitive than usual. The
steering wheel may also be at an angle when
driving straight.
Drive slow ly to your authorized Audi dealer or
qualified workshop to have the malfunction
corrected.
'Tl Dynamic steering: Initializing
If th is driver message appears and the ind ica­
tor light is flashing on the inst rument panel,
dynamic steering* is be ing reinitialized. After
starting the engine, the steering whee l wi ll
move slightly. Re-initialization might be nec­
essary if the steering wheel was moved hard
to the left and right while the vehicle was not moving. The display
goes out as soon as initi­
alization is complete.
Drive slowly to your authorized Audi dealer or
qualified wo rkshop to have the malfunct ion
corrected.
A WARNING
Have the dynamic steering * system mal ­
function repaired as soon as possible by an
authorized Audi dealer or qualified work­
shop -risk of accident!
(D Tips
If the . or '1:I indicator light only stays
on for a short time, you may continue driv­
ing.
- The dynamic steering* stability systems
are not availab le in the event of a system
malfunction .
- For additional information on dynamic
steering*, refer to¢
page 102.
Driving with your
quattro
-
With all-wheel drive, all four wheels ore driv­
en .
General information
With all-wheel drive, power is distributed to
all four wheels. This happens automatically
depending on your driving style and the road
conditions at the time. See also
¢page 195.
A center differential distributes the driving
power variably to the front and rear axle.
It
works together with selective wheel torque
control, which activates when driving through
curves¢
page 196. With the sport differen­
tial*, power distribution to the rear wheels is
variable and can be adjusted with drive se lect
¢ page 102.
The all-wheel drive concept is des igned for
high eng ine power. Your veh icle is except ion­
ally powerfu l and has excellent driving charac­
teristics both under normal driving conditions
and on snow and ice. Always read and follow
safety precautions ¢,&. . .,.

M N <( (.J
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Wheel bolts
Wheel bolts must always be tightened to the
correct torque .
The design of wheel bolts is matched to the
factory installed r ims. If differen t rims are fit­
ted, the correct wheel bolts with the right l ength and correctly shaped bolt heads must
be used. This ensures that wheels are fitted
securely and that the brake system functions
correctly .
In certain circumstances, you may not use
wheel bo lts from a different vehicle -eve n if it
i s the same model
~ page 296.
_&. WARNING
Improperly tig htened or maintained whee l
bolts can become loose ca using loss of
contro l, a co llision and serious persona l in­
jury.
- Always keep the wheel bolts and the threads in the wheel hubs clean so the
whee l bolts can turn easily and be prop­
erly t ightened.
- Never grease or oil the wheel bo lts and
the threads in the wheel hubs. They can become loose wh ile driving if greased or
o iled, even if tightened to the specif ied
torque .
- Only use wheel bolts that belong to the
rim being installed.
- Never use different whee ls bolts on your
vehicle .
-Always maintain the correct tighten ing
torque for the wheel bo lts to reduce the
risk of a wheel loss . If the tightening tor ­
que of the wheel bolts is too low, they
can loosen and come out when the vehi­
cl e is moving.
If the tightening torque is
too high, the whee l bolts and threads
can be damaged and the wheel can be­
come loose.
Q;) Note
The spec ified torque fo r the wheel bo lts is
90 ft lb (120 Nm) w ith a toleran ce of± 7,4
ft lb(± 10 Nm). Torque wheel bo lts diago-
Tire s an d wheel s 269
nally . After changing a whee l, the torq ue
must be checked as soon as possible with a
torque wrench -preferably by an author­
i zed Audi dealer or qualif ied workshop.
Low aspect ratio tires
Your Audi is factory-equ ipped w ith low aspect
ratio tires . These tires have been thoroughly
tested and been selected specifically for your model for their superb perfo rmance, road fee l
and hand ling u nder a variety of driving condi­
tions . Ask your au thorized Aud i dealer for
more details .
T he low aspect ratio of these t ires is ind icated
by a numera l of
55 or l ess in the tire's si ze
designation. The n umera l represents the ra tio
of the ti re's sidewall height in relation to its
tread width expressed in percentage . Conven­
tiona l tires have a height/width ratio of 60 or
more.
The perform ance o f low-a spe ct-r atio tire s is
p ar ticul arl y s ens it iv e to imp ro per infl ation
pressur e. It is t herefo re im porta nt t hat low
a spect ratio t ires are inflat ed to the specified
pr essure and that the inflation pressure is
r e gularly checked and ma int ained. Tire pr es­
s ure s should be check ed at lea st on ce a
month and alwa ys befor e a long trip
~ page 252 , Checking tire pressure.
What you c an do to avoid tire and rim
damage
Low aspect ratio tires can be damaged more
easily by impact w it h potholes, curbs, gull ies
o r r idges on the road, pa rtic ularly if the tire is
u nder infla ted .
In order to minimize the occurrence of impact
damage to the tires of your vehicle, we recom­
mend that you observe the following p re ca u­
tions:
- Always ma inta in recommended inflation
p ressures . Check your tire pressu re eve ry
2 ,000 miles (3,000 km) and add air if neces­
sary .
- Dr ive caref ully on roads wi th potholes , deep
gullies o r ridges. The impact from driv ing ..,. •
•

276 What do I do n ow ?
After changing a wheel
A wheel change is no t complete without the
doing the following .
.. Always store the vehicle tool kit, the jack*
and the replaced tire in the luggage com­
partment ¢
page 134.
.. Check the tire pre ssur e on the spare wheel
immediately after mount ing it .
.,. As soon as possible, have the
tightening
torqu es
on all wheel bol ts checked with a
torq ue wrench. The correct tightening tor ­
que is 90 ft lb (120 Nm) .
.. Have the flat tire
replaced as soon as possi­
ble.
@ Tips
- If you notice t hat the wheel bolts are
corroded and difficult to t urn while
changing a t ire, they should be replaced
before you check the tighten ing torque.
- Drive at reduced speed unt il you have the
tightening torques checked .
- After changing a wheel, the tire pressure
i n a ll four tires must be checked/correct­
ed and the tire pressure mon itor ing indi­
cator must be stored in the MMI
¢ page 272 .
Decorative wheel covers
Applies to vehicles: with decorative wheel covers
T he decora tive wheel covers must be removed
first to access the wheel bolts .
Fig. 210 Cha nging a w hee l: Remov ing t he w heel cove r
Removing
.,. Inse rt the hook (prov ided with the veh icle
tool kit) in t he hole in the wheel hub cove r. ..
Pull off the
de cora tive wheel co ver
¢ fig . 210.
Wheels with wheel bolt caps
Applies to veh icles: w it h w heel bolts with caps
The caps must be removed first from the
wheel bolts before the bolts can be un­
screwed.
Fi g. 211 Cha ng ing a whee l: re m oving t he w hee l b o lt
caps
Removing
.. Push the plastic clip (provided with t he veh i­
cle tool k it) over the wheel bo lt cap until the
inner retainers on the clip align w ith the
edge of the cover.
.,. Remove the cap with the
plastic clip (vehicle
tool kit)
i=> fig . 211 .
Refitting
.. Place the caps over the whee l bolts and
push them back on.
The caps are to protect and keep the wheel bolts clean .

28 0 What do I do no w?
Tires with unidirectional tread design
Tires with unidirectional tread design must be
mounted with their tread pattern pointed in the right direction .
Using a sp are t ire wi th a tread pattern
int ended fo r use in a specific dir ect ion
When us ing a spare tire w ith a tread patte rn
intended for use in a specific direction, please
note the following:
- The direction of rotation is marked by an ar­
row on the side of the tire.
- If the spare t ire has to be installed in the in­
correct direction, use the spare tire only
temporarily since the t ire will not be able to
achieve its optimum performance character­
ist ics with rega rd to aquaplaning, noise and
wea r.
- We recommend that you pay particular at­
tent ion to this fact du ring wet weather and
that you adjust your speed to matc h road
conditions.
- Replace the flat tire w ith a new one and
have it installed on your vehicle as soon as
possible to restore the handling advantages
of a unidirectiona l tire .
Notes on wheel changing
Please read the information c> page 260 , New
t ires and replacing tires and wheels
if you are
going to use a spare tire which is different
from the tires on your vehicle .
After you change a tire :
-Che ck the tire p re ssure on the sp are imme ­
di ately afte r in st a llat ion.
- Ha ve th e wh eel b olt tightenin g torque
che ck e d w ith a torque wrench as soon a s
possible b y you r autho rized Aud i de aler o r
a qu alified ser vice station .
- With ste el and alloy wheel rims , the wheel
bolts are cor rectl y tightened at a torque of
90 ft lb (1 20 Nm ).
- If yo u notice that the wheel bolt s are cor­
r oded a nd d iffi cult to tu rn while changi ng
a t ire, the y should be replaced before you
check the t ightening torq ue. -
Re pl ac e the flat ti re with a new one and
h av e it in st a lled on you r vehicle as soon as
po ssible. Remount th e wheel cov er.
Un til then , driv e with ex tra c are a nd at re­
duc ed sp ee ds.
A WARNING
-
- If you are going to equ ip your vehicle
with tires or rims which differ from those
which were factory installed, then be
sure to read the information
9 page 260,
New tires and replacing tires and
wheels .
-Always make sure the damaged wheel or
even a flat tire and the jack and tool kit
are properly secured in the luggage com­
pa rtment and are not loose in the pas­
senger compartment.
- I n an accident or sudden maneuver they
could fly forwa rd, injuring anyone in the
veh icle.
- Always sto re damaged wheel, jack and
too ls securely in the luggage compart­
ment. Otherwise, in an accident or su d­
den maneuve r they could f ly forward,
causing injury to passengers in the ve hi­
cle.