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4456-3. Do-it-yourself maintenance
6
Maintenance and care
Your vehicle is equipped with a tire pressure warning system that uses tire
pressure warning valves and transmitters to detect low tire inflation pres-
sure before serious problems arise.
XVehicles without the tire inflation pressure display function
If the tire pressure drops below a predetermined level, the driver is
warned by a warning light. ( →P. 507)
XVehicles with the tire inflation pressure display function
●If the tire pressure drops below a predetermined level, the driver is
warned by a screen display and a warning light. ( →P. 5 3 1 )
●The tire pressure detected by the tire pressure warning system can be
displayed on the multi-information display. ( →P. 99)
◆Installing tire pressure wa rning valves and transmitters
When replacing tires or wheels, tire pressure warning valves and trans-
mitters must also be installed.
When new tire pressure warning valves and transmitters are installed,
new ID codes must be registered in the tire pressure warning computer
and the tire pressure warning system must be initialized. Have tire pres-
sure warning valve and transmitter ID codes registered by your Lexus
dealer. ( →P. 4 4 7 )
◆Initializing the tire pressure warning system
■The tire pressure warning system must be initialized in the following
circumstances:
●When rotating the tires.
●When the tire inflation pressure is changed such as when changing
traveling speed or load weight.
When the tire pressure warning system is initialized, the current tire
inflation pressure is set as the benchmark pressure.
Tire pressure warning system
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6-3. Do-it-yourself maintenance
■Low profile tires (except 225/50R17 tires)
Generally, low profile tires will wear more rapidly and tire grip performance will be
reduced on snowy and/or icy roads when compared to standard tires. Be sure to use
snow tires or tire chains on snowy and/or icy roads and drive carefully at a speed
appropriate for road and weather conditions.
■Maximum load of tire
Check that the maximum load of the replacement tire is greater than 1 /2 of the
Gross Axle Weight Ratings (GAWR) of either the front axle or the rear axle, which-
ever is greater.
■Tire types
●Summer tires
Summer tires are high-speed performance tires best suited to highway driving
under dry conditions. Since summer tires do not have the same traction perfor-
mance as snow tires, summer tires are inadequate for driving on snow-covered or
icy roads. For driving on snow-covered roads or icy roads, the use of snow tires is
recommended. When installing snow tires, be sure to replace all four tires.
●All season tires
All season tires are designed to provide better traction in snow and to be ade-
quate for driving in most winter conditions as well as for use year-round. All season
tires, however, do not have adequate traction performance compared with snow
tires in heavy or loose snow. Also, all season tires fall short in acceleration and han-
dling performance compared with summer tires in highway driving.
●Snow tires
For driving on snow-covered roads or icy roads, we recommend using snow tires.
If you need snow tires, select tires of the same size, construction and load capacity
as the originally installed tires. Since your vehicle has radial tires as original equip-
ment, make sure your snow tires also have radial construction. Do not install stud-
ded tires without first checking local regulations for possible restrictions. Snow
tires should be installed on all wheels. (→P. 3 1 8 )
For the GAWR, see the Certification Label.
For the maximum load of the tire, see the load
limit at maximum cold tire inflation pressure
mentioned on the sidewall of the tire.
(
→ P. 5 8 7 )
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4556-3. Do-it-yourself maintenance
6
Maintenance and care
■Instructions for checking tire inflation pressure
When checking tire inflation pressure, observe the following:
●Check only when the tires are cold.
If your vehicle has been parked for at least 3 hours or has not been driven for more
than 1 mile or 1.5 km, you will get an accurate cold tire inflation pressure reading.
●Always use a tire pressure gauge.
It is difficult to judge if a tire is properly inflated based only on its appearance.
●It is normal for the tire inflation pressure to be higher after driving as heat is gener-
ated in the tire. Do not reduce tire inflation pressure after driving.
●Never exceed the vehicle capacity weight.
Passengers and luggage weight should be placed so that the vehicle is balanced.
CAUTION
■Proper inflation is critical to save tire performance
Keep your tires properly inflated.
If the tires are not properly inflated, the following conditions may occur which
could lead to an accident resulting in death or serious injury:
●Excessive wear
●Uneven wear
●Poor handling
●Possibility of blowouts resulting from overheated tires
●Air leaking from between tire and wheel
●Wheel deformation and/or tire damage
●Greater possibility of tire damage while driving (due to road hazards, expansion
joints, sharp edges in the road, etc.)
NOTICE
■When inspecting and adjusting tire inflation pressure
Be sure to put the tire valve caps back on.
If a valve cap is not installed, dirt or moisture may get into the valve and cause an air
leak, resulting in decreased tire inflation pressure.
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6-3. Do-it-yourself maintenance
Wheels
When replacing wheels, care should be taken to ensure that they are
equivalent to those removed in load capacity, diameter, rim width and
inset
*.
Replacement wheels are available at your Lexus dealer.
*: Conventionally referred to as “offset”.
Lexus does not recommend using the following:
●Wheels of different sizes or types
●Used wheels
●Bent wheels that have been straightened
●Steel wheels (F SPORT models only)
●Use only Lexus wheel nuts and wrenches designed for use with your
aluminum wheels.
●When rotating, repairing or changing your tires, check that the wheel
nuts are still tight after driving 1000 miles (1600 km).
●Be careful not to damage the aluminum wheels when using tire chains.
●Use only Lexus genuine balance weights or equivalent and a plastic or
rubber hammer when balancing your wheels.
If a wheel is bent, cracked or heavily corroded, it should be replaced.
Otherwise, the tire may separate from the wheel or cause a loss of han-
dling control.
Wheel selection
Aluminum wheel precautions
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8-1. Specifications
Maintenance data (fuel, oil level, etc.)
*1: Unladen vehicle
*2: Vehicles with 265/35R19 tires
Dimensions and weight
Overall length190.7 in. (4845 mm)
Overall width72.4 in. (1840 mm)
Overall height*157.3 in. (1455 mm)
Wheelbase112.2 in. (2850 mm)
Tread*1
Front62.0 in. (1575 mm)
Rear62.6 in. (1590 mm)
61.4 in. (1560 mm)
*2
Vehicle capacity weight
(Occupants + luggage)825 lb. (370 kg)
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8-1. Specifications
Glossary of tire terminology
Tire related termMeaning
Cold tire inflation pres-
sureTire pressure when the vehicle has been parked for
three hours or more, or has not been driven more
than 1 mile or 1.5 km under that condition
Maximum inflation pres-
sureThe maximum cold inflated pressure to which a tire
may be inflated, shown on the sidewall of the tire
Recommended inflation
pressureCold tire inflation pressure recommended by a man-
ufacturer
Accessory weight
The combined weight (in excess of those standard
items which may be replaced) of hybrid transmission,
power steering, power brakes, power windows,
power seats, radio and heater, to the extent that these
items are available as factory-installed equipment
(whether installed or not)
Curb weight
The weight of a motor vehicle with standard equip-
ment, including the maximum capacity of fuel, oil and
coolant, and if so equipped, air conditioning and
additional weight optional engine
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
Occupant distributionDistribution of occupants in a vehicle as specified in
the third column of Table 1
* below
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 12-volt battery, and special trim
RimA metal support for a tire or a tire and tube assembly
upon which the tire beads are seated
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5958-1. Specifications
8
Vehicle specifications
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
Rim widthNominal distance between rim flanges
Vehicle capacity weight
(Total load capacity)The rated cargo and luggage load plus 150 lb.
(68 kg) times the vehicle’s designated seating capac-
ity
Vehicle maximum load on
the tireThe load on an individual tire that is determined by
distributing to each axle its share of the maximum
loaded vehicle weight, and dividing by two
Vehicle normal load on
the tire
The load on an individual tire that is determined by
distributing to each axle its share of curb weight,
accessory weight, and normal occupant weight (dis-
tributed in accordance with Table 1
* below), and
dividing by two
Weather sideThe surface area of the rim not covered by the
inflated tire
Bead
The part of the tire that is made of steel wires,
wrapped or reinforced by ply cords and that is
shaped to fit the rim
Bead separationA breakdown of the bond between components in
the bead
Bias ply tire
A pneumatic tire in which the ply cords that extend to
the beads are laid at alternate angles substantially
less than 90 degrees to the centerline of the tread
CarcassThe tire structure, except tread and sidewall rubber
which, when inflated, bears the load
ChunkingThe breaking away of pieces of the tread or sidewall
CordThe strands forming the plies in the tire
Cord separationThe parting of cords from adjacent rubber com-
pounds
CrackingAny parting within the tread, sidewall, or innerliner of
the tire extending to cord material
Tire related termMeaning
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8-1. Specifications
CT
A pneumatic tire with an inverted flange tire and rim
system in which the rim is designed with rim flanges
pointed radially inward and the tire is designed to fit
on the underside of the rim in a manner that encloses
the rim flanges inside the air cavity of the tire
Extra load tire
A tire designed to operate at higher loads and at
higher inflation pressures than the corresponding
standard tire
GrooveThe space between two adjacent tread ribs
InnerlinerThe layer(s) forming the inside surface of a tubeless
tire that contains the inflating medium within the tire
Innerliner separationThe parting of the innerliner from cord material in the
carcass
Intended outboard side-
wall
(a) The sidewall that contains a whitewall, bearswhite lettering, or bears manufacturer, brand,
and/or model name molding that is higher or
deeper than the same molding on the other side-
wall of the tire, or
(b) The outward facing sidewall of an asymmetrical tire that has a particular side that must always
face outward when mounted on a vehicle
Light truck (LT) tire
A tire designated by its manufacturer as primarily
intended for use on lightweight trucks or multipur-
pose passenger vehicles
Load ratingThe maximum load that a tire is rated to carry for a
given inflation pressure
Maximum load ratingThe load rating for a tire at the maximum permissible
inflation pressure for that tire
Maximum permissible
inflation pressureThe maximum cold inflation pressure to which a tire
may be inflated
Measuring rimThe rim on which a tire is fitted for physical dimension
requirements
Open spliceAny parting at any junction of tread, sidewall, or
innerliner that extends to cord material
Outer diameterThe overall diameter of an inflated new tire
Tire related termMeaning
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