AUDI A7 2013 Owners Manual

scalding from hot coo lant by following
these steps.
- Turn
off the engi ne and a llow it to cool
down.
- Protect your face, hands and arms from
escapi ng fl uid and steam by cover ing
the cap with a large, thick rag .
- Turn the cap slowly and very ca refully
i n a cou nte r-clockw ise dir ect ion while
a pply ing lig ht, downwa rd p ress ure on
the top of the cap.
- To avo id being burned, do no t sp ill an­
tifree ze o r coolan t on t he exh aust sys­
tem or ho t engine parts . Un der certain
conditions, the ethylene glyco l in en­
gine coolant can catch fire .
- Antifree ze is poisono us. Always store an­
tifreeze in its or iginal co ntainer and we ll
o ut o f the reac h of children.
- If you drain the coolant , it must be
caught and safely stored in a p roper con ­
tainer clear ly marked "poison".
(D Note
- Coolant po llutes the env ironment and
could ca use a n engine fire . Excess coo l­
ant wi ll be forced out through the pres ­
sure re lief va lve in the cap when the en­
gine becomes hot.
- If, in an emergency, only water can be
added , the correct ratio between water
and antifreeze¢
page 237 must be re­
stored as soon as possib le .
@ For the sake of the environment
Drained coolant should not be re used . Al­
ways dispose of used c oolant while observ­
ing all envir onmental regulations .
Radiator fan
The radiator fan switches on automa tically by
itself
An auxiliary e lectric radiator fa n switches on
and
off depending on coolant temperature
and other ve hicle operating conditions.
Checkin g and fillin g 239
After you switch the engine off, the auxi liary
fan can continue running for up to 10 minutes
- even w ith the ign ition off. It can even switch
o n again later by itself¢.& , if
- the temperature of the engine coo lant rises
due to the heat build- up from the engine in
the engi ne compartment, or
- the engine compa rtment heats up because
the vehicle is parked in intense sunlight.
&_ WARNING
--To reduce the risk of persona l in ju ry nev-
er touch the radiator fan .
- The a uxiliary electric fan is tempe rat ure
contro lled and can switch on suddenly
even when the engine is not ru nning.
- The a uxiliary radiator fan sw itches on a u­
tomatically when the engine coo lant
reaches a certai n temperature and will
cont inue to ru n until the coo lant temper­
atur e drops.
Brake fluid
Checking brake fluid level
N
N
N
.,; 0:, a,
Fig. 193 Engin e co mpa rt m ent: cove r on t he bra ke fluid
reservo ir
Before you check anything in the eng ine com­
partment,
alw ays r ead and heed all WARN­
INGS c:> A in Working in the engine compart­
ment on page 230 .
.. Read t he brake fluid level from the brake
fluid reservoir
c:> fig. 193, c:> fig. 189. The
brake fluid level must be between the "MIN"
and "MAX" markings. .,..

24 0 Ch eck ing and filling
The location of the brake fluid reservo ir can be
seen in the engine compartment illustration
¢ page 232.
The fl uid level may drop slightly after some
time due to the automatic adjustment of the
brake pads. This is not cause for alarm.
I f the brake fluid level falls
considerably be­
low the "MIN" mark, the brake warning/ind i­
cator light
1111 (U .S . models)/ . (Canadian
models) will come on¢
page 15. Do not con­
tinue to operate the vehicle. The comp lete
brake system shou ld be thoroughly checked
by an au thorized Audi dealer or other quali­
fied facility and the cause corrected . If the
brake fluid level is too low, the brake warn ing/
indicator light w ill illuminate . Contact an au­
thor ized Audi dealer
imm ediatel y.
Changing brake fluid
Have the brake fluid changed by an experi­
enced technician .
Brake fluid absorbs moisture from the a ir . If
the water content in the brake fluid is too
h igh , corros ion in the brake system may result
after a per iod of t ime . The bo iling po int of the
brake fluid w ill also decrease considerably and
dec rease braking performance.
Therefore, the brake flu id must be changed
ev ery two year s. Always use new b rake fluid
which conforms to Fede ral Motor Vehicle
Standard "FMVSS
116 DO T 4".
The brake flu id reservoir can be difficult to
r each, therefo re , we recommend that you
have the brake fl uid changed by yo ur author­
ized
Audi d ealer. Your dea ler has the correct
too ls, the right brake fluid and the know -how
to do this for you .
A WARNING
-Brake fluid is poisonous . It must be stor ­
ed only in the closed orig inal container
out of the reach of children!
- Brake fa ilure can result from old or inap­
propriate brake fluid. Observe these pre­
caut ions: -
Use only brake fluid that meets SAE
specification
J 1703 and conforms to
Federa l Motor Vehicle Standard
116.
Always check with your authorized Audi
dealer to make sure you are using the
correct brake fluid . The correct type of
brake f lu id is also ind icated on the
brake flu id reservoir.
- T he brake fluid must be new. Heavy use
of the bra kes ca n cause a vapo r lock if
the b rake fluid is left in the system too
l ong . This can seriously affect the effi ­
c iency of the brakes as well as your
safety. This co uld resu lt in an accident.
(D Note
Bra ke fluid will damage the paint of you r
vehicle .
(® For the sake of the environment
Because of the p rob lem of p roper disposal
of b ra ke fluid as well as the spec ial too ls
r equired and the necessary expertise, we
re commend that you have the brake fluid
changed by yo ur authorized Aud i dea ler.
Battery
General information
U nder normal ope rat ing cond itions , the bat­
tery in yo ur Audi does not need any ma inte­
nance. With
high o utside tempe ra tu res or
l ong daily drives we recommend that you have
the e lectrolyte level checked by a service fa­
cility. The electrolyte leve l should a lso be
checked each t ime the battery is charged
<=> page 243.
Have th e battery checked when yo u take your
veh icle in for service. You are well advised to
replace a battery that is o lder than S years .
With certain types of airbag deployment, the battery is disconnected from the veh icle elec­
trical system for safety reasons<=>.&
in Re­
pair , care and dispo sal of the airbags on
page
165.

Disconne cting the batt ery t erminals
Some vehicle functions (power w indow regu ­
l ators, for example) are lost if the battery ter­
minals are disconnected . These functions have
to be re learned after the battery terminals are
connected again. To prevent this, the battery
should only be disconnected from the vehicle
electrical system when absolutely necessary
for repairs .
Vehicles not driven fo r lo ng period s
If you do not drive your vehicle over a period
of several days or weeks, electrical compo­
nents are gradually cut back or switched off .
This reduces energy consumption and main­
tains starting capab ility over a longer per iod
c> page 202 . Some of the convenience func­
tions may not operate, such as the inte rior
lights or power seat adjustment. The conven ­
ience functions will be ava ilable again when
you switch on the ignition and start the en ­
g ine.
Winter operation
D uring the winter months, batte ry capacity
tends to decrease as tempe ratu res d rop . This
is because more power is also consumed while
starting , and the headlights, rear window de ­
fogger, etc., are used more often.
Avoid unnecessary power consumption, par­
ticularly in city t raffic or when traveling on ly
short distances. Let your a uthorized Audi
dealer check the capacity of the vehicle bat­
tery before winter sets inc>
page 243. A well
charged battery w ill not only prevent starting
prob lems when the weather is cold, but will
also last longer .
@ Tips
If your vehicle is left standing for severa l
weeks at extremely low temperatu res, the
veh icle battery should be removed and
sto red where it will not freeze. This will
prevent it from being damaged and hav ing
t o be rep la ced.
Checkin g and fillin g 241
Working on the battery
Be especially careful when working on or near
the battery.
The battery is located in the luggage compart­ ment under the floor. Before you check any­
th ing in the luggage compartment,
read and
he ed all WARNINGS
<=> ..&_ .
Always heed the safet y warnings , when work­
i ng on the vehicle batte ry or the vehicle e lec ­
trical system to prevent inju ry.
The following WARNINGS ar e very
important when wor king on the battery:
Always heed the following WARNING SYM­ BOLS and safety pre cautions when working
on the battery.
Always wear eye protection.
Battery acid contains sulfuri c acid .
Always w ear glove s and eye protec ­
tion.
No
- sparks
- flames
- smoking .
1
When a batter y is charged, it produ­
ce s hydrogen g as which is e xplo sive
and could cause per sonal injury .
---·-
®
Always keep the battery well out of
reach of children .
A WARNING
Whenever working on the battery o r on
the electrical system, there is the risk of injury, accident and even fire. Read and
heed the following WARNINGS :
- Always wear eye protection. Do not let
-
battery ac id or any lead particles get on
your skin or clothing. Shield your eyes. Exp losive gases can cause blindness or
other inju ry.
- Battery acid conta ins sulfuric acid. Sulfu­
ric acid can cause blindness and severe
bu rns.
•
•

242 Checking and filling
-Always wear gloves and eye protection.
Do not tilt the battery because acid
could leak out of the ventilation open­ ings.
- If you get battery acid in your eyes or
on your skin, immediately rinse with
cold water for several minutes and get
medical attention .
- If you should ingest any battery acid,
seek medical attention immediately.
- Do not expose the battery to an open
flame, electric sparks or an open light .
- Do not smoke.
- Do not interchange the positive and neg-
ative cables .
- When working on the battery , be sure
not to short-circuit the terminals with
tools or other metal objects. This would
cause the battery to heat up very quickly,
which could lead to damage or explosion
and personal injury .
- When a battery is charged, it produces
hydrogen gas which is explosive and
could cause personal injury .
- Always keep the battery well out of the reach of children .
- Before work is done on the electrical sys­
tem, disconnect the negative ground ca­ ble.
- Before performing any work on the elec ­
trical system, switch off the engine and
ignition as well as any electrical equip­
ment. The negative cable on the battery
must be disconnected. If you are just go­
ing to replace a light bulb, then it is
enough to switch off the lights.
- Before disconnecting the battery, switch
off the anti-theft alarm system! Other­
wise you will set off the alarm.
- When disconnecting the battery, first
disconnect the negative cable and then
the positive cable.
- Before reconnecting the battery, make sure all electrical consumers are switch­
ed off. Reconnect the positive cable first
and then the negative cable. Never inter­
change the cables - this could start a fire! -
Never charge a frozen or a thawed-out
battery . It could explode! If a battery has
frozen, then it must be replaced. A dis­ charged battery can freeze over at 32 °F
(0 °C) .
-Make sure the vent hose is always attach­
ed to the opening on the side of the bat­
tery .
- Never use batteries which are damaged .
There is the danger of an explosion! Al ­
ways replace a damaged battery.
A WARNING ....__
California Proposition 65 Warning:
- Battery posts, terminals and related ac ­
cessories contain lead and lead com­
pounds, chemicals known to the State of
California to cause cancer and reproduc­
tive problems . Wash hands after han­
dling.
(D Note
- Do not disconnect the vehicle battery
when the ignition is on or when the en­
gine is running, otherwise , you will dam­
age electronic components in the electri­
cal system.
- If your vehicle is going to stand for a
long period of time without being driven,
protect the battery from "freezing", oth­
erwise it will be damaged and will then
have to be replaced.
- When opening the doors, the windows
lower approximately 10 mm automati­
cally. This function is not available when
the battery is disconnected, which
means there is a risk that the door seal
or the window could be damaged .

Battery charging
Starting the engine requires a well charged battery .
Fig. 194 Eng ine co mpa rtmen t: connectors for a charg ­
er a nd jump sta rt cab les
A lwa ys re ad and heed all WARNING S below
c:> &. and c:> &. in Working on the battery on
page 241 .
.. Switch off the ignit ion and all electrical con­
sumers .
.. Make sure the area is well ventilated when
you charge the battery .
.. Open the engine hood
c:> page 230 .
.. Open the red cove r on the posit ive pole
c:>fig. 194.
.. Connect the charger connectors accord ing
to the instructions to the
jump start b olts .
(Bolts under the red cover= "positive", Bolts
with hex head= "negative") .
.. Only now plug the mains lead for the charg­
ing equipmen t into the wall outlet and turn
it on
c:> 8_ .
.. Ma ke sur e t he charging rat e is not over
30 amp s/14 .8 Vol t.
.. When the batte ry is fully charged: Turn the
charging eq uipment off and remove the
ma ins lead from the wall outlet .
.. Now remove the clamps for the charging
equipment.
.. Close the red cover on the positive pole.
.. Close the hood
c:> page 2 31.
A discharged battery can free ze at tempera­
tures of on ly 32 F
0 (0 °C). A llow a frozen bat­
tery to thaw completely before attempt ing to
charge it
c:> .&. . However, we recommend not
using a thawed battery again because the bat-
Checkin g and fillin g 243
tery casing can be cracked due to ice fo rma ­
tion and can leak battery acid.
Battery charging (Maximum charging rate
of 30 amps /14.8 Volt )
When charging at low voltages (e.g. with a
trickle cha rger ), the battery cables do not
have to be disconnected f irst . The battery
caps should
not be opened when charging a
battery.
It is not necessary to remove the battery from
the luggage compartment, and it is a lso not
necessary to disconnect the cab les.
Fast ch arging the batte ry (charging rat e
a bove 14.8 V olt s)
For technica l reasons do not use a battery
charger that uses voltage greater than 14.8
Volts to charge your vehicle's battery .
A WARNING
-
Charging a battery can be dangerous .
- Always follow the operating instructions
provided by the battery charger manu­
facturer when charg ing your battery .
- Never charge a frozen battery. It may ex­
plode because of gas trapped in the ice .
Allow a frozen battery to thaw out first.
- Do not reuse batteries wh ic h were fro­
zen. The battery housing may have
cracked and weakened when the battery
froze.
- Cha rge the battery in a well ventilated
area . Keep away from open flame or elec­
trical spar k. Do not smo ke. Hyd rogen gas
generated by the battery is explos ive.
- To reduce the danger of explosion, never
connect or d isconnect charger cab les
while the charger is ope rat ing.
- Fast cha rging a batte ry is dange rous and
should only be at tempted by a compe­
tent techn ic ian wi th the prope r equip­
ment .
- Ba ttery acid that may spi ll dur ing charg­
ing should be washed off with a solution
of warm water and baking soda to neu ­
tralize the ac id.

24 4 Ch eck ing and filling
Never use a fast charger as a booster to
start the engine. This will seriously dam­
age sensitive electronic components, such
as control units, relays, rad io, etc., as well
as the battery charger.
Battery replacement
The new battery must have the same specifi­
cations and dimensions as the original equip­
ment battery .
Intelligent energy management in your veh i­
cle is respons ible for d istributing the electr i­
cal energy throughout your vehicle
c::> page 202. The intell igent energy manage­
ment system w ill keep the engine battery
cha rged bette r than vehicles w ithout t his sys­
tem. To make sure the additional e lectrica l en­
e rgy is availab le once again after you have
changed the battery, we recommend that you
install batteries of the same type and man u­
facture only (the same as those installed at
the time your vehicle was delivered). Specifi­
cations are listed on the battery hous ing. Your
author ized dealer must code the battery in
the energy management system to enable you
to use the energy management funct ions cor­
rectly after replac ing the battery .
The new battery must have the same capacity ,
voltage (12-volts), amperage, const ruct ion
and p lug sealing.
When insta lling the battery, make sure the ig­
n ition and all e lectr ica l consumers are sw itch ­
ed off .
{[) Note
Make sure the venti lation hose on the s ide
of the battery is connected, ot herwise
fumes or battery ac id can leak out.
- Vehicles with the Start-Stop-System* are
equipped with a special cycle-proof AGM
batte ry. Insta lling a differe nt type of
batte ry can ca use p rob lems in the vehi­
cle elect rical system. When rep lacing the
vehicle bat tery, always ins ta ll one wi th the same specifica
tions as the o rigina l
battery .
~ For the sake of the env ironment
B ec ause o f th e p rob lem of p roper disposal
of a battery, we recommend your author­
ized Audi dealer change the battery fo r
you. Batteries contain sul fur ic acid and
l ead and must always be disposed of prop­
erly in compl iance with all environmental
regulations. Disposing of veh icle batter ies
i mproperly is very dange rous to the envi­
r onment.
Windshield/headlight
washer container
Fi g. 195 Eng in e compa rt m ent: cove r on t he w inds hield
and head lig ht* was her flu id reservo ir
T he washer fluid co nta iner is mar ked w ith the
symbol$ on its cap
c::> fig. 195, c::> fig. 189.
.,. Before yo u check anything in the engine
compa rtment,
alwa ys read and heed all
WARNINGS
c::> A in Working in the engine
compartment on page 230 .
.. Lift the fi ller cap tongue to add washer flu­
id . You can fi ll the containe r to the top .
.. Press the cap back onto the filler neck after
filling the container .
You can find the reservoi r
capacity in the table
in
c::> page 287.
C lean water should be used when filling up . If
possible, use soft water to prevent scaling on
washe r jets. Always add a g lass cleaner so lu­
t ion (with frost protection in the winter).

(D Note
Do not mix engine coolant antifreeze or
any other add itives to fi ll u p the w ind­
shie ld washer reservoir.
Checkin g and fillin g 245
•
•

24 6 T ire s and whee ls
Tires and wheels
Tires
General notes
Tires may be the least appreciated and most
abused parts of a motor vehicle .
Tires may be the least appreciated and most
abused parts of a motor vehicle . Tires are,
however, one of the most important parts of a
vehicle, particularly considering the compara­
tive ly small patch of rubber on each tire that
assures that all -important contact between
you, your vehicle and the road.
Maintaining the correct tire pressure, making
sure that your vehicle and its tires do not have
to carry more weight than they can safe ly han­
d le, avoiding damage from road hazards and
reg ularly inspecting t ires for damage includ­
ing cuts, slashes irregu la r wear and overall
condition are the most important things that
you can do to he lp avoid sudden tire failure in­
cluding tread separation and blowouts.
A vo idin g dama ge
I f you have to drive over a curb or similar ob­
stacle, drive very slow ly and as close as possi ­
ble at a right angle to the curb.
A lways keep chem icals including grease, oil,
gasoline and b rake fluid off the tires.
Inspect the tires regularly for damage (cuts,
cracks or bl isters, etc.). Remove any foreign
bod ies embedded in the treads.
St orin g tire s
Mark tires when you remove them to indicate
the direction of rotation . Th is ensures you to
be ab le to mount them correctly when you re­
install them.
When removed, the wheels or tires should be
stored in a cool, dry and preferably dark place .
Store tires in a vertical position if they are not mounted on rims, in a horizontal position if
they are mounted on rims. N
ew tir es
New t ires have to be broken in¢&,. .
The tread depth of new t ires may vary, accord­
ing to the type and make of t ire and the tread
pattern .
Hidden damag e
Damage to tires and r ims is often not readily
vis ible . If you notice unusual vibrat ion or the
vehicle pulls to one s ide, th is may ind icate
that one of the t ires has been damaged . T he
t ir es must be checked immed iate ly by an au­
tho rized Aud i dea le r or q ualified wor kshop.
Unidirecti onal t ires
A un idirectional tire can be identified by ar­
rows on the sidewall, that po int in the direc­
t ion the t ire is designed to rotate. You must
fol low the specified direction of rotation . This
is necessary so that these tires can develop
their optimum characteristics regarding grip, road noise, wear and hydrop laning resistance.
For more information
¢ page 274.
A WARNING
-New tires or tires that are old, worn or
damaged cannot provide maximum con­
trol and braking ability .
-
-New tires tend to be slippery and must
be broken in . To reduce the risk of losing
control, a collision and ser ious personal
injuries, drive w ith special ca re for the
fi rst 350 m iles (560 km).
- Driving with worn or damaged tires can lead to loss of control, sudden tire fail­
ure, including a blowou t and sudden de­
flation, c rashes and serious personal in­
juries . Have worn or damaged tires re­
p laced immediate ly .
- Tires age even if they are not being used
and can fai l sudden ly, especially at high
speeds. Tires that are more than 6 years
old can only be used in an emergency
and then w ith special care and at low
speed.

-Never mount used tires on yo ur vehicle if
yo u 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.
- If you notice unusual vibration or if the
vehicle pulls to one side when d riving, al­
ways stop as soon as it is safe to do so
and check the wheels and tires for dam­
age .
(D Note
Please note that summe r and wi nte r tires
are designed for the cond itions that are
Glossary of tire and loading terminology
Accessory weight means the comb ined weight (in excess of
those sta ndard items which may be rep laced)
of au toma tic transmission, power steer ing ,
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 rat io o f the height 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 overa ll handling on dry
pavement .
Bead
means the part of the t ire t hat is made o f
steel wires, wrapped or reinforced by ply cords
and that is shaped to fit the r im.
Bead separation
means a b reakdown of the bond between
components in the bead .
Cord means the strands forming the plies in the
tire.
Tire s an d wheel s 24 7
typica l in those seasons . Aud i recommends
using winter tires during the winter
months . Low temperatures signif icant ly
dec rease the e lasticity of summer t ires,
which affects tract ion and brak ing ability.
If summer t ires are used i n very co ld tem ­
peratures, cracks ca n form o n the tread
bars , res ulting in perma nen t tire damage
that can cause loud driving noise and un­
bala nced ti re s. Audi i s not respon sible for
th is type of damage .
Cold tire inflation pressure
means the t ire p ress ure recommended by t he
vehicle manufacture r fo r a tire o f a des ignated
s ize t hat has not bee n driven for more than a
coup le o f miles (k ilometers) at low speeds in
the three hour period before the tire press ure
is m easured or adjusted.
Curb weight
me ans the we ight of a motor ve hicle with
st andard equipmen t incl ud ing the max imum
capacity of fuel, oi l, and coolant, air condi ­
tioning and additional weig ht of optiona l
equipment.
Extra load tire
means a t ire design to oper ate a t higher load s
and at higher inflation pressures than the cor­
responding standa rd tire . Extra load tires may
be identified as "XL", "x l", "EXTRA LOAD", o r
"RF" on the sidewal l.
Gross Axle Weight Rating ("GAWR")
me ans the load-ca rry ing capac ity of a single
axle system , measured at the tire -ground in­
te rfaces.
Gross Vehicle Weight Rating ( "GVWR ")
mea ns the maximum total loaded we ight of
the ve hicl e. .,..
•
•

248 Tires and wheels
Groove
means the sp ace between two ad jacent tread
ribs .
Load rating (code )
means the maximum load that a tire is rated
to carry fo r a g iven inflat ion pressu re. You
may not find this in fo rmat io n on all t ires be­
c a use i t is no t re quir ed 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 t he sum of:
(a) Curb weig ht
(b) Accessory weight
( c ) Vehicle c apa city we ight, and
(d) Prod uction opt ions we ight
Maximum (permissible) inflation pressure
means t he maximum co ld inflation pressure
to which a tire may be inflated . Also called
"maxim um infla tion p ressure ."
Normal occupant weight
means 150 lbs. (68 k ilog rams) times the
n umber of occupants seated in the vehicle up
to the tota l seating capacity of yo ur vehicle .
Occupant distribution
means dist ribution o f occ upants in a veh icle.
Outer diameter
means t he overa ll diamete r of a n inflated new
tire.
Overall w idth
means the linea r distance between the exter i­
ors of the sidewalls of an inflated tire, includ ­
ing e levations due to labeli ng, decorations, or
p rotectiv e bands o r ribs .
Ply
means a layer of rubber-coated para llel cords.
Production options weight
me ans the com bine d we igh t of tho se ins tall ed
regular prod uction opt ions we ighing over 5
lb s. (2 .3 kg) in excess of those stan da rd item s
which they replace, not previously considered
in curb weight or accessory we ight, including
heavy duty brakes, ride levelers , roof rack ,
heavy duty battery, and special tr im .
Radial ply tire
means a pneumat ic tire in wh ich the ply cords
t h at exte nd t o the beads are laid at substa n­
t ia lly 90 deg rees to the center line of the
tread .
Recommended inflation pressure
see<=> page 247, Cold tire inflation pressure.
Reinforced tire
means a t ire des ign to operat e at h igher loads
and a t higher in flation pressures than t he cor­
re spondi ng s tand ard tire. Reinfor ce d tires
may be iden tifie d as "X L" "xl" "E X TRA LOAD"
' ' '
or "RF " on the sidewa ll.
Rim
means a metal s upport for a ti re or a tire and
tube assembly upon whi ch t he tire beads are
sea ted.
Rim diameter
means nom inal d iameter of the bead seat. If
you change your wh eel s ize, you wi ll have to
purchase new ti res to match the new r im di­
ameter.
Rim size designation
means r im diameter and width .
Rim width
means nominal d istance between rim fla nges .
Sidewall
means tha t po rtion of a tire betwee n the
t read and be ad.