Page 445 of 493
CHASSIS
423
NOTICE
Avoid overfilling, or the power steering could be
damaged.
When adding the power steering fluid, avoid spilling
it. The generator under the power steering reservoir
could be damaged if fluid is spilled on it.
CHECKING SUSPENSION FLUID
AHC
63X007c
1“MAX” line 2“MIN” line
Under the unloaded condition, check the Suspension
Fluid AHC in the following way.
1. Start the engine and put the vehicle height in the “LO” (Low)
mode and then “N” (Normal) mode.
2. Turn off the ignition switch about 30 seconds after the “N”
(Normal) mode indicator light comes on.
3. Make sure the fluid level is between “MAX” and “MIN”.
If the fluid level is lower than “MIN”, have suspension fluid AHC
filled by your Lexus dealer.
Page 447 of 493

CHASSIS
425
Type B
The recommended cold tire inflation pressures, tire
size and the combined weight of occupants and
cargo (vehicle capacity weight) are described on the
tire and loading information label.
You should check the tire inflation pressure every two
weeks, or at least once a month. And do not forget the
spare! The pressure for the spare tire should be 220 kPa
(2.2 kgf/cm
2 or bar, 32 psi).
The following instructions for checking tire inflation
pressure should be observed:
The inflation pressure should be checked only
when the tires are cold. If your vehicle has been
parked for at least 3 hours and has not been driven for
more than 1.5 km or 1 mile since, you will get an
accurate cold tire inflation pressure reading.
Always use a tire pressure gauge. The appearance
of the tire can be misleading. Besides, tire inflation
pressures that are even just a few pounds off can
degrade ride and handling.
Do not bleed or reduce tire inflation pressure after
driving.
It is normal for the tire inflation pressure to
be higher after driving.
Never exceed the vehicle capacity weight.
Passengers and luggage weight should be located so
that the vehicle is balanced.
Page 449 of 493
CHASSIS
427
CAUTION
Keep your tires properly inflated. Otherwise, the
following conditions may occur and cause an
accident resulting in death or serious injuries.
Low tire pressure (underinflation):
Excessive wear
Uneven wear
Poor handling
Possibility of blowou ts from an overheated tire
Poor sealing of the tire bead
Wheel deformation and/or tire separation
A greater possibility of tire damage from road
hazards
High tire pressure (overinflation):
Poor handling
Excessive wear
Uneven wear
A greater possibility of tire damage from road
hazards
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CHASSIS
429
1 Tire size: For details, see “Tire size” on page
430.
2 DOT and Tire Identification Number (TIN): For
details, see “DOT and Tire Identification Number
(TIN)” on page 430.
3 Location of tread wear indicators: For details,
see “Checking and replacing tires” on page 438.
4 Tire ply composition and materials : Plies
mean a layer of rubber −coated parallel cords.
Cords mean the strands forming the plies in the
tire.
5 Summer tire or all season tire: An all season
tire has “M+S” on the sidewall. The tire not
marked with “M+S” is a summer tire. For details,
see “Types of tires” on page 436.
6 Radial tires or bias ply tires: A radial tire has
“RADIAL” on the sidewall. A tire not marked with
“RADIAL” is a bias −ply tire.
7 “TUBELESS” or “TUBE TYPE”: A tubeless tire
does not have a tube inside the tire and air is
directly filled in the tire. A tube type tire has a
tube inside the tire and the tube maintains the air
pressure.
8 Load limit at maximum cold tire inflation
pressure: For details, see “Checking and
replacing tires” on page 438.
9 Maximum cold tire inflation pressure: This
means the pressure to which a tire may be
inflated. For recommended cold tire inflation
pressure, see “Tires and wheels” on page 420.
10 Uniform tire quality grading: For details, see
“Uniform tire quality grading” that follows.
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CHASSIS
432
Uniform tire quality grading
This information has been prepared in accordance
with regulations issued by the National Highway
Traffic Safety Administration of the U.S. Department
of Transportation. It provides the purchasers and/or
prospective purchasers of Lexus vehicles with
information on uniform tire quality grading.
Your Lexus dealer will help answer any questions
you may have as you read this information.
DOT quality grades All passenger vehicle tires
must conform to Federal Safety Requirements in
addition to these grades. Quality grades can be
found where applicable on the tire sidewall between
tread shoulder and maximum section width. For
example: Treadwear 200 Traction AA Temperature
A
Treadwear
− The treadwear grade is a comparative
rating based on the wear rate of the tire when tested
under controlled conditions on a specified government
test course. For example, a tire graded 150 would wear
one and a half (1 − 1/2) times as well on the government
course as a tire graded 100. The relative performance
of tires depends upon the actual conditions of their use,
however, and may depart significantly from the norm
due to variations in driving habits, service practices and
differences in road characteristics and climate. Traction
AA, A, B, C
− The traction grades, from highest
to lowest, are AA, A, B and C, and they represent the
tire’s ability to stop on wet pavement as measured under
controlled conditions on specified government test
surfaces of asphalt and concrete. A tire marked C may
have poor traction performance.
Warning: The traction grade assigned to this tire is
based on braking (straight ahead) traction tests and
does not include cornering (turning) traction.
Temperature A, B, C
− The temperature grades are A
(the highest), B, and C, representing the tire’ s resistance
to the generation of heat and its ability to dissipate heat
when tested under controlled conditions on a specified
indoor laboratory test wheel. Sustained high
temperature can cause the material of the tire to
degenerate and reduce tire life, and excessive
temperature can lead to sudden tire failure. The grade
C corresponds to a level of performance which all
passenger car tires must meet under the Federal Motor
Vehicle Safety Standard No. 109. Grades B and A
represent higher levels of performance on the laboratory
test wheel than the minimum required by law.
Warning: The temperature grades for this tire are
established for a tire that is properly inflated and not
overloaded. Excessive speed, underinflation, or
excessive loading, either separately or in combination,
can cause heat buildup and possible tire failure.
Page 456 of 493

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434
Tire related termMeaning
Normal occupant weight68 kg (150 lb.) times the number of occupants specified in the second \
column of
Table 1 that follows
Production options weight
the combined weight of those installed regular production options weighi\
ng over
2.3 kg (5 lb.) in excess of those standard items which they replace, n\
ot previously
considered in curb weight or accessory weight, including heavy duty brak\
es, ride
levelers, roof rack, heavy duty battery, and special trim
Vehicle capacity weight
(Total load capacity)the rated cargo and luggage load plus 68 kg (150 lb.) times the vehicl\
e’s
designated seating capacity
Intended outboard
sidewall
(a) the sidewall that contains a whitewall, bears white lettering or bears
manufacturer, brand, and/or model name molding that is higher or deeper than
the same molding on the other sidewall of the tire, or
(b) the outward facing sidewall of an asymmetrical tire that has a particula\
r side that must always face outward when mounted on a vehicle
Occupant distributiondistribution of occupants in a vehicle as specified in the third column \
of Table 1 that
follows
Rima metal support for a tire or a tire and tube assembly upon which the ti\
re beads are
seated
Rim diameter
(Wheel diameter)nominal diameter of the bead seat
Page 457 of 493

CHASSIS
435
Tire related termMeaning
Rim size designationrim diameter and width
Rim type designationthe industry of manufacturer’s designation for a rim by style or code
Rim widthnominal distance between rim flanges
Vehicle maximum load on
the tirethe load on an individual tire that is determined by distributing to eac\
h axle its
share of the maximum loaded vehicle weight and dividing by two
Vehicle normal load on
the tirethe load on an individual tire that is determined by distributing to eac\
h axle its
share of the curb weight, accessory weight, and normal occupant weight
(distributed in accordance with Table 1 that follows) and dividing by two
Weather sidethe surface area of the rim not covered by the inflated tire
Table 1 – Occupant loading and distribution for vehicle normal load for various designated seating capacities
Designated seating capacity, Number of occupants
Vehicle normal load,
Number of occupantsOccupant distribution in a normally loaded vehicle
2 through 422 in front
5 through 1032 in front, 1 in second seat
Page 460 of 493

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438
CHECKING AND REPLACING TIRES
When to replace your tires
63X006c
1New tread 2Tread wear indicator
3Worn tread
Replace the tires when tread wear indicators show.
The location of tread wear indicators is shown by
the “TWI” or “
Δ” marks, etc., molded on the sidewall
of each tire.
The tires on your Lexus have built −in tread wear
indicators to help you know when the tires need
replacement. When the tread depth wears to 1.6 mm
(0.06 in.) or less, the indicators will appear. If you can
see the indicators in two or more adjacent grooves, the
tire should be replaced. The effectiveness of snow tires is lost if the tread
wears down below 4 mm (0.16 in.).
If you have tire damage such as cuts, splits, cracks
deep enough to expose the fabric, or bulges
indicating internal damage, the tire should be
replaced.
If a tire often goes flat or cannot be properly repaired due
to the size or location of a cut or other damage, it should
be replaced. If you are not sure, consult with your Lexus
dealer.
If air loss occurs while driving, do not continue driving.
Driving
even a short distance can damage a tire beyond
repair.
Any tires which are over 6 years old must be
checked by a qualified technician even if damage is
not obvious.
Tires deteriorate with age even if they have never or
seldom been used.
This also applies to the spare tire and tires stored for
future use.