AUDI S8 2015 Owners Manual

- the temperature of the engine coolant rises
due to th e heat bui ld-up from the engine in
the engine compartment, or
- the engine compartment heats up because
the vehicle is parked in intense sunlight.
.&_ WARNING
- To reduce the r isk of personal injury nev­
er touch the radiator fan.
- The auxiliary electr ic fan is temperature
controlled and can switch on sudden ly
even when the engine is not runn ing.
- The auxiliary radiator fan switches on au­ tomat ically when the engine coolant
reaches a certain temperature and will
continue to run until the coolant temper ­
at ure drops.
Brake fluid
Checking brake fluid level
The brake fluid level can be checked with a
quick glance.
N N
-N
i
F ig . 2 05 Eng ine co mpartmen t: cove r on the b rake f lui d
r eservo ir
Before you check anything in th e engine com­
partment,
alwa ys read and he ed all WARN­
INGS c::> .&. in Working in the engine compart­
ment on page 2 28.
~ Read the brake fluid level from the brake
fl uid reservo ir ~
fig . 205, c::> page 230. The
brake f luid leve l must be betwee n the "M IN"
and "M AX" marki ngs.
The location of the brake fl uid reservo ir can be
see n in t he engi ne comp artment illus trati on
c::> page 230.
Checkin g and fillin g 239
The fluid level may d rop slightly afte r some
time due to the automatic adjustment of the
brake pads . T his is not cause for alarm .
If the brake flu id leve l falls considerably be­
low the "MIN" mark, the brake warning/indi­
cator light . (U.S. models) . (Canadian
models) w ill come on
~ page 14 . Do not con­
tin ue to operate the vehicle . The complete
brake sys tem should be thoroughly checked
by an authorized Audi dea ler or other quali ­
fied facility and the cause corrected.
If the
brake f lu id leve l is too low, the brake warning/
indica tor ligh t will illumi nate. Conta ct an au­
thorized Aud i de aler
immediately .
Changing brake fluid
Have the brake fluid changed by an experi­
en ced technician.
B rake fluid absorbs moisture from the air . If
the water content in the brake fluid is too
high, co rrosion in the brake system may resu lt
after a pe riod of time. The boiling point of the
brake f lu id will also dec rease conside rably and
decrease brak ing performance.
T herefo re , the bra ke fluid must be changed
every tw o year s. Always use new br ake f lu id
which con forms to Federal Mo tor Veh icle
Standard " FMVSS 116 DOT 4".
T he bra ke fluid reservo ir can be d iff icu lt to
reach, the refore, we recommend that you
have the bra ke fluid changed by your author­
ized
Audi dealer. Your dealer has the cor rect
tools, the right brake fluid and the know -how
to do this for you.
A WARNING
---- Brake flu id is poisonous. It must be stor­
ed only in the closed or iginal container
out of the reach of children!
- Brake failure can resu lt from old or inap­
prop riate brake f lu id. Observe these pre­
cautions:
- U se only brake fluid tha t meets SAE
specificat ion
J 1703 and conforms to
Federa l Motor Vehicle Standard 116.

24 0 Ch eck ing and filling
Always check wi th your a uthorized Audi
dealer to make s ure you are using the
correct brake flu id. The correct type of
brake fluid is also indicated on the
brake fluid reservoir.
- The brake fluid must be new. Heavy use
of the brakes can cause a vapor lock if
the brake fluid is left in the system too
long. This can ser ious ly affect the effi­
ciency of the b ra kes as well as yo ur
safety. This could result in an acc ident.
(D Note
Brake flu id will damage the paint of your
veh icle.
@ For the sake of the environment
Because of the problem of proper d isposa l
of brake flu id as wel l as the special tools
requ ired and the necessary expert ise, we
recommend that you have the b rake fluid
changed by your author ized Audi dealer.
Battery
General information
Under
normal operating conditions, the bat­
tery in your Audi does not need any mainte­
n ance . With
high outside temperatures or
l ong daily dr ives we recommend that you have
the elec trolyte level checked by a service fa­
cili ty. The e lec trolyte level sho uld a lso be
checked each time the battery is charged
¢ page 242.
Have the b attery checked when you ta ke yo ur
ve hicl e in for service. Yo u are well adv ise d to
replace a battery that is older than S years .
W ith certa in types of airbag deployment, the
battery is d isconnected from the vehicle ele c­
tr ica l system for sa fety reasons¢
& in Re­
pair, care and disposal of the airbags on
page 165.
Disconnecting the battery terminals
Some veh icle func tions (power w indow regu­
l ato rs, for example) a re los t if the b attery ter- mina
ls are disconnected. These functions have
to be relearned after the battery termina ls are
connected aga in. To prevent th is, the battery
sho uld only be disconnected from the ve hicle
electrical system when abso lutely necessary
for repairs.
Vehicle s not driven for long peri ods
If you do not d rive your vehicle over a period
of several days or weeks, e lectr ica l compo ­
nents are gradually cut back or sw itched off.
This reduces energy consumption and ma in­
ta ins start ing capability over a longer period
¢
page 202. Some of the convenience func­
t ions may not ope rate, such as the inter ior
li gh ts or the power seat adjus tment. The con­
venience func tions will be ava ilable ag ain
when you switch on the ignition and start the
engine .
Winter operation D uring the winte r months, battery capac ity
tends to de crease as temperatures drop. This
is beca use more power is also consumed wh ile
sta rting, and the headlights, rear window de ­
fogger, etc ., are used more often .
Avoid unnecessary power consumpt ion, p ar­
t icu lar ly in city traffic or whe n traveling only
short distances. Let yo ur au thorized Aud i
dealer check the capacity of the vehicle bat ­
tery before winter sets in ¢
page 242. A well
charged battery will not on ly prevent starting
problems when the weather is cold, but will
also last longer.
(!) Tips
If your vehicle is left standing for several
weeks at extremely low temperatures, the
vehicle battery sho uld be removed and
stored where it w ill not freeze. This will
prevent it from be ing damaged and having
to be repla ced.

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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
thing in the luggage compartment,
r ea d and
h ee d all WARNINGS
~ ,&.
Always heed the safet y warn ing s, when work­
i ng on the vehicle battery or the veh icle elec ­
tr ical system to prevent injury .
The following WARNINGS are very
impo rtant when work ing on the battery:
Al ways heed the follow ing WARNING SYM-
BOL S an d saf ety pr eca utions when wo rking
on the b atter y.
®)
Alway s w ea r eye protection .
A
Batter y aci d contain s sulfu ric acid.
Alw ay s w ear g lo ves and ey e prot ec-
tion .
@
No
-spa rk s
- flam es
- sm oking .
~
When a batte ry is charge d, it produ -
c es hyd rogen gas whi ch i s ex plosi ve
an d cou ld cause pers ona l injury .
®
Alway s keep the b atter y well out of
reach of child re n .
A WARNING
Whenever working on the battery or on
the electrical system, there is the r isk of
injury, acc ident and even fire. Read and
heed the following WARNINGS:
- Always wear eye p rotection . Do not let
battery acid or any lead particles get on
your sk in or cloth ing . Sh ield your eyes .
E xplosive gases can cause blindness or
other injury .
- Battery acid contains sulfuric acid . Sulfu­
ric acid can cause blindness and severe
burns .
Checkin g and fillin g 241
-Always wear g loves and eye protection.
Do not tilt the battery because acid
could leak out of the ventilation open­
i ngs .
- If you get battery acid in your eyes or
on your skin, immediately rinse with
cold water for several minutes and get
med ical attent ion .
- If you should ingest any battery acid,
seek medical attention immediately .
- Do not expose the battery to an open
f lame, e lectr ic sparks or an open light.
- Do not smoke.
- Do not interchange the positive and neg-
ative cables.
- When working on the battery, be su re
not to short-circuit the termina ls with
too ls 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 explos ive and
could cause personal in ju ry .
- Always keep the battery well out of the reach of children .
- Before work is done on the electrical sys­
tem, disconnect the negat ive ground ca­
ble.
- Before performing any work on the e lec ­
trical system, switch off the eng ine and
ignit ion as well as any electrical equip­
ment. The negative cable on the battery
m ust be disconnected. If yo u are just go­
ing to replace a light bulb, then it is
enough to switch off the lights .
- Before disconnec ting the battery, switch
off the anti -theft alarm system! Other ­
wise you wi ll set off the alarm.
- When disconnecting the battery, f irst
disconnect the negative cab le and then
the positive cab le .
- Before reconnecting the battery, ma ke
sure all e lectrica l consumers are switch-
ed off . Reconnect the pos it ive cable first
and then the negative cable . Never inter­
change the cables - this could start a fire!
~
•
•

24 2 Ch ecking and filling
-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 dange r 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.
- Do not d isconnect the veh icle battery
when the ignition is on or when the en­
gine is running, otherwise, you will dam­
age electronic components in the electri­
ca l system.
- If your veh icle is go ing to stand for a
l ong period of time without being driven,
protect the battery from "freezing", oth­
erwise it w ill be damaged and w ill then
have to be replaced.
Battery charging
Starting the engine requires a well charged
battery.
Fig. 2 06 Engine compartme nt: connecto rs fo r a cha rg ­
e r and jump star t cab les
Alwa ys re ad and h eed all WARNINGS below
¢
A and ¢ A in Working on the battery on
page
241.
.. Switch off the ignition and all electrical con­
sumers .
.. Make sure the area is we ll ventilated when
you charge t he battery.
.. Open the eng ine hood ¢
page 228.
.. Remove the cover (D by pressing on the ar­
row ¢
fig. 206 .
.. Open the cover @on the pos it ive terminal.
.. Connect the charger connectors according to
the inst ructions to the
jump start b olt s.
(Bolts under the red cover = "posit ive", Bo lts
w ith hex head= "negative") .
.. On ly now plug the mains lead for the charg ­
ing equipment into the wal l o utlet and turn
iton ¢
,&.
.. M ake sure the cha rging rate is not over
3 0 amps /14.8 Volt .
.. When the battery is fully charged: Turn the
charg ing equipment off and remove the
mains lead from the wall out let .
.. Now remove the clamps for the charging
equ ipment.
.. Close the red cover on the positive pole .
.. Close the hood ¢
page 229.
A discharged battery can freeze at tempera ­
tu res of only 32 F
0 (0 °C). Allow a frozen bat­
te ry to thaw completely before attempting to
charge it¢ & . However, we recommend not
us ing a thawed battery again because the bat­
tery casing can be cracked due to ice forma ­
t ion and can leak battery acid.
Battery cha rging (M ax imum charging rate
of 30 amp s/14.8 Volt )
When charg ing at low vo ltages (e.g. with a
t rickle cha rge r), the battery cables do not
have to be disconnected first. The battery
caps should
not be opened when charg ing a
battery.
It is not necessary to remove the battery from
the luggage compartment, and it is also not
necessary to d isconnect the cab les .

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Fa st charging the b att ery (charging rate
abo ve 14.8 Vo lt s)
Fo r technical reasons do not use a batt ery
charger that uses vo ltage g reater 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 charging your battery.
- Never charge a fro zen battery. It may ex­
plode because of gas trapped in the ice.
Allow a frozen battery to thaw out first .
- Do not reuse batteries which were fro­
zen. The battery housing may have
cracked and weakened when the battery
froze .
- Charge the battery in a well ventilated
area . Keep away from open flame or elec­
trical spark . Do not smoke . Hydrogen gas
gene rated by the battery is exp losive.
- To reduce the danger of explosion , never
co nnect or disconnect cha rger cables
wh ile the charger is operating.
- Fast charg ing a battery is dangerous and
should only be attempted by a compe­
t ent technicia n w ith the proper eq uip­
ment.
- Battery a cid that may spill d uring charg­
ing should be washed off wit h a solution
of warm wa ter and ba king soda to neu ­
tralize the acid .
CD Note
Never use a fast charge r as a booster to
s tart the engine. This will se rio usly d am­
age sensitive elect ronic components, such
as control units, relays, radio, etc., as we ll
as the battery charger .
Checking and fillin g
Battery replacement
The new battery must have the same specifi­
cations and dimensions as the original equip­
ment battery.
In telligen t energy managemen t in your vehi­
cle is responsible for distributing the electri ­
cal ene rgy throughout your vehicle
¢ page 202. The intelligent energy manage­
ment system will keep the engine battery
c h arged better than vehicles without this sys ­
tem. To make sure the additional electrica l en ­
ergy is avai lab le once again afte r yo u have
changed the battery, we recommend that you
insta ll batteries of the same type and m anu­
facture only (the same as those installed at
the time your ve hicle was delivered) . Specif i­
cat ions are listed on the battery housing . Your
authorized dea le r must code the battery in
the energy management system to enab le you
to use the ene rgy manageme nt func tions cor ­
re ct ly afte r replacing the battery.
The new battery must have the same capacity,
vo ltage
( 1 2 volts), amperage, const ruction
and plug seal ing .
When installing the battery, make sure the ig­ nition and a ll elect rical consume rs are switch­
ed off .
CD Note
- Make sure the ventilation hose on the
side of the battery is connected, other­
w ise fumes or battery a cid ca n leak out .
- Veh icles with the Start-Stop-System* are
e quipped with a spec ial cycle-p roof AGM
battery. Install ing a d iffe rent type of
ba ttery c an cause problems in the vehi ­
cle e lectrical system. Whe n replacing the
vehicle battery, always install one w ith
the same specifications as the origina l
battery.
- Battery mounts and clamps must a lways
be sec ured correct ly .
- Read and fo llow the wa rnings under
¢ page 241, Working on the battery be-
fore per forming any work on the battery . ..,_
243
•
•

244 Checking and filling
@ For the sake of the environment
Because of the problem of proper disposa l
of a battery, we recommend your author­
ized Audi dealer change the battery for
you. Batter ies contain sulfuric acid and
lead and must always be disposed of prop­
erly in compliance w ith all environmental
regu lations . D isposing of vehicle batteries
improperly is very dangerous to the envi­ ronmen t.
Windshield/headlight
washer container
Fig. 207 Engine compartment: cover on the windshield
was her flui d reservo ir
The washer fluid container is marked with the
symbol~ on its cap
c::> fig. 207, c::> page 230 .
.. Before you check anyth ing in the engine
compartment,
always read and heed all
WARNINGS c::> A in Working in the engine
compartment on page 228 .
.. lift the filler cap tongue to add washer flu­
id . You can fill the container to the top .
.. Press the cap back onto the filler neck after
filling the container.
You can find the reservoir
capacity in the table
in
c::>page 288.
Clean water should be used when filling up. If
possible, use soft water to prevent scaling on
washer jets. Always add a glass cleaner solu­
tion (with frost protection in the winter).
(D Note
Do not mix engine coolant antifreeze or
any other additives to fill up the wind­
shield washer reservoir.

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Tires and wheels
Tires
General notes
Tires may be the least appreciated and most
abus ed parts of a motor vehicle .
Tires may be the least ap preciated and most
a b used parts of a motor vehicle . T ires are,
however, one of the most important parts of a
vehi cle, particularly considering the compara­
tively small patch of rubber on eac h tire that
assures that a ll- important contact between
you, you r vehicle and the road.
Ma intaining the correct tire pressure, mak ing
sure that your vehicle and its tires do not have
to carry mo re weight than they can safe ly han­
d le, avoiding damage from road ha za rds and
r eg ularly inspec ting t ires for damage i nclud­
ing cuts, slashes irreg ular wear and ove ra ll
condition are the most important things that
you can do to he lp avoid s udden tire failure in­
cluding tread separat ion and b lowouts.
Avoiding damage If you have to d rive ove r a curb or similar ob­
stacle, drive very slow ly and as close as possi ­
b le at a right angle to the curb.
A lways keep chemicals incl ud ing grease, o il ,
gasoline and brake fluid off the t ires .
I nspect the t ires regularly for damage (cuts,
cracks or b listers, e tc.). Remove any fo reign
bod ies embedde d in the t reads.
Storing tires Mark t ires when you remove them to indicate
the direction of rotation . T his ensures you to
be ab le to mount them correctly when you re­
in stall them .
When removed, the whee ls or t ires should be
sto red in a cool, d ry and preferably dark place .
Store tires in a vertical pos ition if they are not
mounted on r ims, in a horizontal pos it ion if
they are mounted on rims .
Tires an d wheel s 245
New tires
New tires h ave to be broken in ¢ & .
The tread depth of new t ires may va ry, accord­
ing to the type a nd make of t ire and the tread
pa tte rn.
Hidden damage
Damage to tires and r ims is ofte n not readily
visible . If you notice unusual v ib rat io n or the
vehicle p ulls to one s ide, th is may ind icate
that one of the t ires has been damaged . T he
tir es m ust be che cked immed iate ly by an au­
t horized Audi dea le r or q ua lified wor kshop .
Unidirectional tires
A un idirec tional tire can be identified by ar­
rows on the s idewa ll, that po int in the direc­
tion the t ire is desig ned to rotate. You mus t
f ol low the specified d irection o f rotation . T his
is necessary so that these tires can develop
their optimum characteristics regarding grip, road noise, wear and hydrop laning resistance.
For more information
¢ page 275.
A WARNING
New tires or t ires that are o ld, worn or
damaged can not provide maximum con­
trol and braking ability .
-
-New tires tend to be slippery and must
be broken in. To reduce the r isk of losing
contro l, a co llision and ser ious personal
in ju ries, d rive with special ca re fo r the
fi rst 350 m iles ( 560 km).
- Driving with worn or damaged tires can
le ad to loss of control, sudde n tire fail ­
ure, including a blowout and sud den de­
fla tion, c ras hes and se riou s personal in­
juries . Have wo rn or d amaged t ires re­
placed immediate ly.
- Ti res age even if they are no t being used
an d can fai l sudden ly, especially at hig h
spee ds. 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.
•
•

24 6 T ire s and whee ls
- 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.
- If you notice unusual vibration or if the
vehicle pulls to one side when driving, 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 summer and winter
tires are designed for the cond itions that
a re typ ica l in those seasons. Aud i recom­
mends using w inter t ires d uring the win-
Glossary of tire and loading terminology
Accessory weight
means t he 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 available as factory-installed equip­
ment (whether installed or not).
Aspect ratio
means t he ratio of the height to the width of
the tire in percent. Numbers of 55 or lower in­
d icate a low sidewall for improved steer ing re­
sponse and better overall handling on dry pavement .
Bead
means the pa rt of the tire t hat is made of
steel wires, wrapped or 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 t he strands forming the plies in the
tire. ter months.
Low tempe ratu res signifi­
cantly decrease the elasticity of summer
tires, which affects traction and braking ability. If summer tires are used in very
co ld temperatures, cracks can form on
the tread bars, resu lting in permanent
tire damage that can cause loud driving noise and unbalanced tires. Aud i is not
responsib le for this type of damage.
- Burn ished, polished or chromed rims
must not be used in winter weather. The
surface of the rims does not have suff i­
c ien t corrosion protect io n for this and
cou ld be pe rmanently damaged by road
salt or simi lar substances. This damage
is not covered by war ranty.
Cold tire inflat ion pre ssure
means the t ire press ure recommended by the
vehicle manufacturer for a tire o f a des ignated
size that has not been driven for more than a
coup le of miles (ki lometers) at low speeds in
the three hour period before the tire press ure
is measured or adjusted.
Curb weight
means the weight of a motor vehicle w ith
standard equipment including the maximum
capacity of fuel, o il, and coolant, air cond i­
tion ing and additional weight of optiona l
equipment.
E x tra load tire
means a tire design to operate at higher loads
and at higher inflation pressures than the cor­
responding standard tire. Extra load tires may
be identified as "XL", "xl", "EXTRA LOAD", or
"RF" on the sidewall.
Gross A xle Weight Rating ("GAWR ")
means the load-carrying capacity of a single
axle system, measured at the tire-ground in -
terfaces.
IJ>,

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Tires and wheels 24 7
Gross Vehicle Weight Rating ("GVWR") Ply
means the maximum total loaded weight of
the vehicle .
Groove
means the space between two adjacent tread
ri bs.
Load rating (code)
means the maximum load that a tire is rated
to carry for a given inflat ion pressure . You
may not find this informat ion on all tires be­
cause it is not requ ired 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 the sum of:
(a) Curb weight
(b) Accesso ry weight
(c) Vehicle capacity weight, and
(d) Production opt ions we ight
Maximum (permissible) inflation pressure
means the maximum co ld inf lation pressure
to which a tire may be inflated . Also called
"maximum inflation press ure."
Normal occupant weight
means 150 lbs . (68 kilograms) times the
number of occupants seated in the vehicle up
to the tota l seating capacity of your vehicle.
Occupant distribution
means distribution of occupants in a veh icle.
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. means a layer of
rubber-coated parallel cords.
Production options weight
means the combined weight of those installed
regular production opt ions we ighing over 5
lbs. (2.3 kg) in excess of those standa rd items
which they replace, not previously considered
in curb weight or accessory weight, including
heavy duty brakes, ride levelers, roof rack,
heavy duty battery, and spec ial trim.
Radial ply tire
means a pneumatic tire in which the ply cords
that extend to the beads are laid at substan­
tially 90 degrees to the centerline of the
tread.
Recommended inflation pressure
see ~ page 246, Cold tire inflation pressure .
Reinforced tire
means a tire design to operate at higher loads
and at higher inflation pressures than t he cor­
responding standard tire. Reinforced tires
may be identified as "XL", "xl", "EXTRA LOAD",
or "RF" on the sidewal l.
Rim
means a metal support for a tire or a t ire and
tube assembly upo n which the tire beads are
seated .
Rim diamete r
means nominal diameter of the bead seat. If
you change your wheel s ize, you wi ll have to
purchase new tires to match the new r im di­
ameter .
Rim size designation
means rim diameter and width.
Rim width
means nominal distance between rim flanges.
Sidewall
means that portion of a t ire between the
tread and bead .
•
•

248 Tires and wheels
Speed rating (letter code)
means the speed at wh ic h a tir e is des igned to
be d riven for extended per io d s of t ime. The
ratings range from 93 mph (150 km/h) to
186 mph (298 km/h)
¢ page 257. You may
not find this in format ion on all tires because
it is not required by law.
The speed rating letter code, w here a pplica­
b le, is molded on the tire s idewa ll and indi­
cates the maxim um permissible road speeds
¢ &. in Winter tires on page 261.
Tire pressure monitoring sy stem*
means a system tha t d etects when one or
mo re of a vehicle's t ires are under inflated and
i llum inates a low t ire p ress ure warn ing te ll­
tale.
Tread
means t hat port ion of a tire tha t comes into
con tact w it h t he road.
Tread separation
means pull ing away of the t read from the t ire
car cass .
Treadwear indicators (TWI)
means t he projections withi n the pr inc ipal
g rooves designed to give a v isua l ind ication of
the deg rees of wea r of the tre ad . See
¢
pag e 255, Tread W ear Indicator (TWI) for
mo re inf ormat io n on measu ring tire we ar.
Uniform Tire Quality Grading
is a tire i nfo rmation system developed by the
United States Nat io nal Highway Traffic Safety
Admin istration (N HTSA) that is designed to
h e lp buye rs make re lative compa risons among
tires. The UT QG i s no t a safety r ating and no t a
g uar antee t hat a t ire will las t fo r a presc ribed
n umber of m iles (kilome ters) or pe rform in a
certain way. It s imply gives ti re bu ye rs addi­
tional information to combine with other con -s
iderations, such as p rice , brand loya lty and
dealer recommendations. Un der UTQ G, tires
are grade d by the t ire manufacturers in three
areas : treadwea r, traction, and temperature
resistance. The UTQG informat ion on the tires,
molded into the sidewalls .
U.S. DOT Tire Identification Number (TIN )
This is the tire's "se ria l numbe r" It begins
with the letters "DOT" and ind icates that the
t ire meets all federa l standards . The next two
numbers or letters ind icate the plant where it
was ma nufactu red, and the last four numbe rs
r eprese nt the week and year of ma nufact ure.
Fo r exampl e,
DOT ... 2214 ...
means that the tire was produced in t he 22nd
wee k of 2014. The ot her numbers are market­
ing codes that may or may not be used by the
t ire manufacturer. This information is used to
contact consumers i f a tire defect requires a
r ecall .
Vehicle capacity weight
means the rated cargo and luggage load plus
150 lbs. (68 k ilograms) times the vehicle's to­
ta l seating capacity as listed on the label lo­
cated on the driver's side B-pilla r.
Vehicle maximum lo ad on the tire
means that load on an individua l tire that is
determined by distributing to eac h axle its
share of the maxim um loaded vehicle weight
and divid ing by two .
Vehicle normal load on the tire
means that load on an individua l t ir e that is
determined by distributing to eac h ax le its
share of the curb weight, accessory weight,
and normal occ upant weig ht (d istr ibuted in
accorda nce wit h tab le below ¢
page 249)
and divid ing by two .