2018 VOLVO XC90 TWIN ENGINE inflation pressure

WHEELS AND TIRES
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Tread wear indicator
The tread wear indicator shows the status of the
tire's tread. The tread wear indicator is a narrow elevated
strip running across the tire's longitudinal tread
grooves. The letters TWI (Tread Wear Indicator)
are visible on the side of the tire. When approxi-
mately 1.6 mm (1/16 inch) is left on the tread,
the tread will be at the same height as the tread
wear indicator. Replace the tire as soon as possi-
ble. Tires with low tread offer very poor traction in
rain or snow.
Related information
•
Tires (p. 550) Tire terminology
The following is a glossary of tire-related terms.
The tire suppliers may have additional markings,
notes or warnings such as standard load, radial
tubeless, etc.
• Tire information placard: A placard show-
ing the OE (Original Equipment) tire sizes,
recommended inflation pressure, and the
maximum weight the vehicle can carry.
• Tire Identification Number (TIN): A number
on the sidewall of each tire providing infor-
mation about the tire brand and manufactur-
ing plant, tire size and date of manufacture.
• Inflation pressure: A measure of the
amount of air in a tire.
• Standard load: A class of P-metric or Metric
tires designed to carry a maximum load at 35
psi [37 psi (2.5 bar) for Metric tires]. Increas-
ing the inflation pressure beyond this pres-
sure will not increase the tires load carrying
capability.
• Extra load: A class of P-metric or Metric
tires designed to carry a heavier maximum
load at 41 psi [43 psi (2.9 bar) for Metric
tires]. Increasing the inflation pressure
beyond this pressure will not increase the
tire's load carrying capability.
• kPa: Kilopascal, a metric unit of air pressure.
• PSI: Pounds per square inch, a standard unit
of air pressure. •
B-pillar: The structural member at the side
of the vehicle behind the front door.
• Bead area of the tire: Area of the tire next
to the rim.
• Sidewall of the tire: Area between the bead
area and the tread.
• Tread area of the tire: Area of the perime-
ter of the tire that contacts the road when
mounted on the vehicle.
• Rim: The metal support (wheel) for a tire or a
tire and tube assembly upon which the tire
beads are seated.
• Maximum load rating: a figure indicating
the maximum load in pounds and kilograms
that can be carried by the tire. This rating is
established by the tire manufacturer.
• Maximum permissible inflation pressure:
the greatest amount of air pressure that
should ever be put in the tire. This limit is set
by the tire manufacturer.
• Recommended tire inflation pressure:
inflation pressure, established by Volvo,
which is based on the type of tires that are
mounted on a vehicle at the factory. This
information can be found on the tire inflation
placard(s) located on the driver's side B-pillar
and in the tire inflation table in this chapter.
• Cold tires: The tires are considered to be
cold when they have the same temperature
as the surrounding (ambient) air. This tem-

||WHEELS AND TIRES
554
perature is normally reached after the vehicle
has been parked for at least 3 hours.
Related information
•
Tires (p. 550) Tire sidewall designations
The following information can be found on a
tire's sidewall. Federal law mandates that tire manufacturers
place standardized information on the sidewall of
all tires (see the illustration).
The vehicle has been certified with certain combi-
nations of wheels and tires.
The following information is listed on the tire
sidewall:
The tire designation:
NOTE Please be aware that the following tire desig-
nation is an example only and that this par-
ticular tire may not be available on your vehi-
cle.
1.
215: the width of the tire (in millimeters)
from sidewall edge to sidewall edge. The
larger the number, the wider the tire.
2. 65: The ratio of the tire's height to its width
in percent.
3. R: Radial tire (the designation RF and the symbol indicate that the vehicle is
equipped with optional self-supporting run
flat tires 3
.
4. 15: The diameter of the wheel rim (in
inches).
5. 95: The tire's load index. In this example, a
load index of 95 equals a maximum load of
1521 lbs (690 kg).
6. H: The tire's speed rating, or the maximum
speed at which the tire is designed to be
driven for extended periods of time, carrying
a permissible load for the vehicle, and with
correct inflation pressure. For example, H
indicates a speed rating of 210 km/h
(130 mph). 3
Self-supporting run flat tires may not be available on all models.

WHEELS AND TIRES
555
NOTEThe tire's load index and speed rating may
not appear on the sidewall because they are
not required by law.
7.
M+S or M/S = Mud and Snow, AT = All Ter-
rain, AS = All Season
8. U.S. DOT Tire Identification Number
(TIN): This begins with the letters "DOT" and
indicates that the tire meets all federal
standards. The next two numbers are the
factory code where the tire was manufac-
tured, the next two are the tire size code and
the last four numbers represent the week
and year the tire was made. For example,
0717 means that the tire was manufactured
during week 7 of 2017. The numbers in
between are marketing codes used at the
manufacturer's discretion. This information
helps a tire manufacturer identify a tire for
safety recall purposes.
9. Tire Ply Composition and Material Used:
Indicates the number of plies indicates or the
number of layers of rubber-coated fabric in
the tire tread and sidewall. Tire manufactur-
ers also must indicate the ply materials in the
tire and the sidewall, which include steel,
nylon, polyester, and others.
10. Maximum Load: Indicates the maximum
load in pounds and kilograms that can be
carried by the tire. Refer to the vehicle's tire information placard located on the B-Pillar
for the correct tire pressure for your vehicle.
11. Treadwear, Traction, and Temperature
grades.
12. Maximum permissible inflation pressure:
the greatest amount of air pressure that
should ever be put in the tire. This limit is set
by the tire manufacturer.
Speed SymbolA tire's Speed Symbol (SS) indicates the maxi-
mum speed for which the tire has been certified
and should be at least equivalent to the vehicle's
top speed.
Winter tires, with or without studs, are exceptions
and may use a lower SS. When winter tires are
installed, the vehicle may not be driven faster
than the tires' SS.
The vehicle's speed should always be determined
by the posted speed limit and traffic and road
conditions, not the tire's SS.
The following table indicates the maximum per-
missible speed for each SS. M 130 km/h (81 mph)
Q

160 km/h (100 mph)
T 190 km/h (118 mph)
H 210 km/h (130 mph) V 240 km/h (149 mph)
W

270 km/h (168 mph)
Y 300 km/h (186 mph)
WARNING •
The wheel and tire sizes for your Volvo
are specified to meet stringent stability
and handling requirements. Unapproved
wheel/tire size combinations can nega-
tively affect your vehicle's stability and
handling.
• Any damage caused by installation of
unapproved wheel/tire size combinations
will not be covered by your new vehicle
warranty. Volvo assumes no responsibility
for death, injury, or expenses that may
result from such installations.
Related information
•Tires (p. 550)

WHEELS AND TIRES
* Option/accessory.557
Checking tire pressure
Correct inflation pressure helps improve driving
stability, save fuel and increase the service life of
the tires.
Tire pressure decreases over time, which is nor-
mal. Tire pressure also varies depending on the
ambient temperature. Driving on under-inflated
tires could cause the vehicle to overheat and lead
to damage. Tire pressure affects traveling com-
fort, road noise and driving characteristics.
Check the pressure in the tires every month. Use
the recommended inflation pressure for cold tires
for optimal tire performance and wear. Under-
inflated or over-inflated tires could cause uneven
tread wear.
Use an air pressure gauge and check the infla-
tion pressure on all the tires, including the spare
tire 4
, at least once a month and before long trips.
Volvo strongly recommends buying a reliable air
pressure gauge, as the automatic gauges provi-
ded at service stations may be inaccurate.
WARNING •
Under-inflation is the most common
cause of tire failure and may result in
severe tire cracking, tread separation, or
"blow-out," with unexpected loss of vehi-
cle control and increased risk of injury.
• Under-inflated tires reduce the load car-
rying capacity of your vehicle.
Cold tiresInflation pressure should be checked when the
tires are cold.
The tires are considered to be cold when they
have the same temperature as the surrounding
(ambient) air.
This temperature is normally reached after the
vehicle has been parked for at least 3 hours.
After driving for approximately 1.6 km (1 mile),
the tires are considered to be warm. If you need
to drive longer than that to inflate the tires, check
and record the inflation pressure of the tires first
and inflate accordingly when you arrive at the
pump.
When the ambient temperature changes, so does
the inflation pressure. A 10-degree temperature
drop causes a corresponding drop in inflation
pressure of 1 psi (7 kPa). Check the inflation
pressure of the tires regularly and adjust to the correct pressure, which can be found on the vehi-
cle's tire information placard or certification label.
If you check inflation pressure when the tires are
warm, you should never release air. The tires
become warm after driving and it is normal for
warm tires to have an inflation pressure above
the recommended pressure for cold tires. A warm
tire with an inflation pressure equal to or under
the recommended pressure for cold tires could
be significantly under-inflated.Related information
•
Adjusting tire pressure (p. 558)
• Recommended tire pressure (p. 559)
• Tire pressure monitoring system* (p. 559)
• Tires (p. 550) 4
Not available in all models.

WHEELS AND TIRES
558Adjusting tire pressure
Tire pressure decreases over time, which is nor-
mal. The tire pressure must therefore be
adjusted to maintain the recommended tire pres-
sure.
Use the recommended inflation pressure for cold
tires for optimal tire performance and wear.
NOTE To help prevent incorrect inflation pressure,
pressure should be checked when the tires
are cold. The tires are considered to be cold
when they have reached the same tempera-
ture as the ambient temperature (about 3
hours after the vehicle was last driven). After
driving for a few kilometers, the tires will warm
up and the pressure will increase.
1. Remove the valve cap from the tire and press
the air pressure gauge firmly onto the valve.
2.

Inflate to the recommended inflation pres-
sure. 3. Screw the valve cap back on.
NOTE •
After inflating a tire, always replace the
valve cap to help prevent valve damage
caused by gravel, dirt, etc.
• Use plastic valve caps only. Metal caps
could corrode and become difficult to
remove. 4. Visually inspect the tire to make sure there
are no nails or other embedded objects that
could puncture the tire and cause air leak-
age.
5.

Check the sidewalls to make sure there are
no gouges, cuts, bulges or other irregulari-
ties.
6. Repeat this procedure for each tire, including the spare tire 5
.
NOTE If you have overfilled the tire, release air by
pushing on the metal stem in the center of
the valve. Then recheck the pressure with
your tire gauge.
Related information
•
Recommended tire pressure (p. 559)
• Checking tire pressure (p. 557)
• Inflate tires with the compressor included in
the tire sealing system (p. 577)
• Approved tire pressure (p. 665) 5
Not available on all models.

WHEELS AND TIRES
}}
* Option/accessory. 559
Recommended tire pressure
The tire pressure placard on the driver's side B
pillar (between the front and the rear door) indi-
cates tire pressure for different loads and speed
conditions. The placard specifies the designation for the fac-
tory-mounted tires on the vehicle, as well as load
limits and inflation pressures.
Related information
•
Checking tire pressure (p. 557)
• Approved tire pressure (p. 665) Tire pressure monitoring system*
The tire pressure monitoring system, Tyre
Pressure Monitoring System (TPMS), provides a
warning symbol in the instrument panel if pres-
sure is too low in one or more tires. Symbol
Explanation This symbol illuminates to indicate
low inflation pressure.
If there is a system malfunction, the
inflation pressure warning symbol
will flash for approximately one
minute and then glow steadily.
System descriptionThe tire pressure monitoring system measures
differences in rotational speed between the
wheels through the ABS system to determine if
the tires are properly inflated. If inflation pressure
in a tire is too low, its diameter (and consequently
its rotational speed) changes. By comparing the
tires with each other, the system can determine if
the pressure in one or more tires is too low.
General information about the tire pressure
monitoring system
In the following description, the tire monitoring
system is generally referred to as TPMS.
Each tire, including the spare tire (if provided)
6
,
should be checked monthly when cold and infla- ted 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 label,
you should determine the proper tire inflation
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 pres-
sure telltale when one or more of your tires is
significantly 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 on a significantly under-inflated tire cau-
ses the tire to overheat and can lead to tire fail-
ure. Under-inflation also reduces fuel efficiency
and tire tread life, and may affect the vehicle's
handling and stopping ability. Please note that
the TPMS is not a substitute for proper tire main-
tenance, and it is the driver's responsibility to
maintain correct tire pressure, even if under-infla-
tion has not reached the level to trigger illumina-
tion of the TPMS low tire pressure telltale.
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate when the
system is not operating properly. The TPMS mal-
function indicator is combined with the low tire
pressure telltale. When the system detects a mal-
6
Not available on all models.

||WHEELS AND TIRES
* Option/accessory.
560 function, the telltale will flash for approximately
one minute and then remain continuously illumi-
nated. This sequence will continue upon subse-
quent vehicle start-ups as long as the malfunc-
tion exists. When the malfunction indicator is illu-
minated, 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 alter-
nate tires and wheels allow the TPMS to con-
tinue to function properly.
Messages in the instrument panelIf tire pressure is too low, the low tire pressure
warning symbol is shown in the instrument panel
along with a message.
• Tire pressure low Check tires, calibrate
after fill
• Tire pressure system Temporarily
unavailable
• Tire pressure system Service required
To keep in mind
•Always calibrate the system after changing
wheels or adjusting tire pressure. See the tire pressure placard on the driver's side B pillar
for Volvo-recommended tire pressures.
• If you switch to a tire of another size than the
factory-mounted tires, the system must be
calibrated for these tires to avoid false warn-
ings.
• If a spare wheel 7
is used, it is possible that
the tire pressure monitoring system will not
work correctly due to the differences
between the wheels.
• The system does not replace the need for
regular tire inspection and maintenance.
• It is not possible to deactivate the tire pres-
sure monitoring system.
WARNING •
Incorrect inflation pressure could lead to
tire failure, which could cause the driver
to lose control of the vehicle.
• The system cannot predict sudden tire
damage.
Related information
• Recommended tire pressure (p. 559)
• Viewing tire pressure status in the center
display* (p. 562)
• Action when warned of low tire pressure
(p. 563) •
Calibrating the tire pressure monitoring sys-
tem* (p. 561) 7
Not available on all models.

||WHEELS AND TIRES
* Option/accessory.
562
NOTE Always remember to calibrate the Tire Pres-
sure Monitoring System when the wheels
have been changed or the tire inflation pres-
sure has been corrected according to the tire
pressure decal or tire inflation pressure table.
If correct reference values have not been set,
the system cannot issue low tire pressure
alerts correctly.
The vehicle must be stationary with the
engine running to access the calibration but-
ton and to start the calibration process.
WARNING
The exhaust gases contain carbon monoxide,
which is invisible and odorless but very poi-
sonous. For this reason, always perform the
calibration procedure outdoors or in a work-
shop with exhaust gas evacuation equipment.
Related information
•
Recommended tire pressure (p. 559)
• Adjusting tire pressure (p. 558)
• Viewing tire pressure status in the center
display* (p. 562)
• Action when warned of low tire pressure
(p. 563)
• Tire pressure monitoring system* (p. 559) Viewing tire pressure status in the
center display*
With the system for tire pressure monitoring,
Tyre Pressure Monitoring System (TPMS), tire
pressure status can be viewed in the center dis-
play.
Checking status1. Open the Car status app in App view. 2.
Tap TPMS to display the status of the tires.
Status indicator light
The graphic in the center display shows the sta-
tus of each tire 8
. Green tire:
• Inflation pressure is above the warning
threshold.
Yellow tire:
• The tire's inflation pressure is too low. Stop
and check/inflate the tire as soon as possi-
ble. Recalibrate the system after adjusting
the tire pressure.
All tires yellow:
• The inflation pressure is too low in one or
more tires. Stop and check/inflate the tires
as soon as possible. Recalibrate the system
after adjusting tire pressure.
All tires gray:
• Calibration in progress.
• Status unknown. 8
The illustration is generic. Layout may vary depending on vehicle model \
or software version.