2010 Lexus IS250 tire size

533
6-1. Specifications
6
Vehicle specifications
Type F
■Compact spare tire
Ti r e s i z eFront tires: 225/40R18 88W
Rear tires: 255/40R18 95W
Front and rear tire inflation pres-
sure
(Recommended cold tire inflation
pressure)
Driving under normal conditions
Front:
35 psi (240 kPa, 2.4 kgf/cm
2 or bar)*
Rear:
38 psi (260 kPa, 2.6 kgf/cm
2 or bar)*
*: When driving at high speeds above 100 mph
(160 km/h), in countries where such speeds are
permitted by law, add 7.2 psi (50 kPa, 0.5 kgf/
cm
2 or bar) to the front tires and rear tires.
Never exceed the maximum cold tire inflation
pressure indicated on the tire sidewall.
Wheel sizeFront wheels: 18  8J
Rear wheels: 18 8 1 /2J
Wheel nut torque76 ft•lbf (103 N•m, 10.5 kgf•m)
Ti r e s i z e
Ty p e A
T125/70D17 98M
Ty p e B
T145/70D17 106M
Tire inflation pressure
(Recommended cold tire inflation
pressure)
60 psi (420 kPa, 4.2 kgf/cm2 or bar)
Wheel size17  4T

538
6-1. Specifications
Tire information
Ty p i c a l t i r e s y m b o l s
Standard tire
Compact spare tire
Tire size (P. 540)
DOT and Tire Identification Number (TIN) (P. 540)
Location of treadwear indicators (P. 4 1 4 )
Tire ply composition and materials
Plies are layers of rubber-coated parallel cords. Cords are the strands
which form the plies in a tire.

540
6-1. Specifications
Typical DOT and tire identification number (TIN)
DOT symbol
*
Tire Identification Number (TIN)
Tire manufacturer's identifica-
tion mark
Tire size code
Manufacturer's optional tire
type code (3 or 4 letters)
Manufacturing week
Manufacturing year
*: The DOT symbol certifies that
the tire conforms to applicable
Federal Motor Vehicle Safety
Standards.
Tire size
■Typical tire size information
The illustration indicates typical
tire size.
Ti r e u s e
(P = Passenger car,
T = Temporary use)
Section width (millimeters)
Aspect ratio
(tire height to section width)
Tire construction code
(R = Radial, D = Diagonal)
Wheel diameter (inches)
Load index (2 or 3 digits)
Speed symbol
(alphabet with one letter)

544
6-1. Specifications
Maximum inflation pres-
sureThe maximum cold inflated pressure to which a tire
may be inflated, shown on the sidewall of the tire
Maximum loaded vehicle
weight
The sum of:
(a) Curb weight
(b) Accessory weight
(c) Vehicle capacity weight
(d) Production options weight
Normal occupant weight150 lb. (68 kg) times the number of occupants speci-
fied in the second column of Table 1
* that follows
Production options
weight
The combined weight of installed regular production
options weighing over 5 lb. (2.3 kg) in excess of the
standard 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 special trim
Vehicle capacity weight
(Total load capacity)The rated cargo and luggage load plus 150 lb. (68
kg) times the vehicle's designated seating capacity
Occupant distributionDistribution of occupants in a vehicle as specified in
the third column of Table 1
* below
Recommended inflation
pressureCold tire inflation pressure recommended by a man-
ufacturer.
RimA metal support for a tire or a tire and tube assembly
upon which the tire beads are seated
Rim diameter
(Wheel diameter)Nominal diameter of the bead seat
Rim size designationRim diameter and width
Rim type designationThe industry manufacturer's designation for a rim by
style or code
Tire related termMeaning

556
6-3. Initialization
Items to initialize
ItemWhen to initializeReference
Engine oil maintenance
dataAfter changing engine oilP. 4 0 3
Tire pressure warning
system
• When rotating the tires with differing
front and rear tire inflation pressures.
• When changing the tire inflation
pressure by changing traveling
speed.
• When changing the tire size.
P. 4 1 5
The following items must be initialized for normal system operation in cases
such as after the battery is reconnected, or maintenance is performed on
the vehicle.

572
Alphabetical index
Tachometer
Tacho indicator...................................... 151
Tachometer ............................................. 151
Tail lights
Switch ....................................................... 165
Talk switch .............................................. 303
Telephone switch ..................................302
Theft deterrent system
Alarm ..........................................................88
Engine immobilizer system ............. 86
Theft prevention labels ..........................90
Tire inflation pressure ......................... 425
Tire information
Glossary................................................. 543
Size ...........................................................540
Tire identification number .............540
Uniform tire quality grading ...........541
Tires
Chains .......................................................210
Checking ................................................. 414
If you have a flat tire .......................... 492
Inflation pressure................................ 425
Inflation pressure sensor..................416
Information............................................538
Replacing ............................................... 492
Rotating tires .......................................... 414
Size ........................................................... 529
Snow tires ................................................210
Tools ........................................................... 492
Total load capacity ...............................209Towing
Dinghy towing ............................ 215, 216
Emergency towing ............................. 461
Trailer towing ........................................ 214
TRAC ..........................................................196
Traction control.......................................196
Transmission shift switches.................142
Trip meter ................................................... 151
Trunk
Extending trunk space.....................357
Opener ...................................................... 47
Trunk light
Trunk light ................................................ 48
Wattage ................................................. 534
Turn signal lights
Replacing light bulbs ....................... 452
Switch ........................................................ 147
Wattage ................................................. 534
Vanity lights
Vanity lights.......................................... 340
Wattage ................................................. 534
Vanity mirrors ........................................ 340
VDIM...........................................................196
Vehicle dynamics integrated
management .........................................196
Vehicle identification number...........521
Vehicle stability control .......................196
Ventilators ................................................ 351
Voice command switch ..................... 302
VSC .............................................................196T
V