2009 Lexus GS450h tire type

233
2-5. Driving information
2
When driving
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
Regulations on the use of tire chains
● Regulations regarding the use of tire chains vary according to location
and type of road. Always check local regulations before installing
chains.
● Use SAE Class “S” type radial tire chains, with the exception of radial
cable chains or V-bar type chains.
• Install the chains on the rear tires.
• Refer to the explanation that comes with the tire chains for installa-
tion instructions.
● Retighten the chains after driving 1 /4 - 1 /2 mile (0.5 - 1.0 km).
■When driving the vehicle
Accelerate the vehicle slowly and drive at a reduced speed suitable
to road conditions.
■ When parking the vehicle
Park the vehicle and move the shift lever to “P” without setting the
parking brake. The parking brake may freeze up, preventing it from
being released. If necessary, block the wheels to prevent inadvert-
ent sliding or creeping.
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235
2-5. Driving information
2
When driving
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
CAUTION
■Driving with snow tires
Observe the following precautions to reduce the risk of accidents.
Failing to do so may result in a loss of vehicle control and cause death or serious
injury.
●Use tires of the size specified for your vehicle.
●Maintain the specified level of tire inflation pressure.
●Do not drive in excess of 75 mph (120 km/h), regardless of the type of snow tires
being used.
●Use snow tires on all, not just some wheels.
■Driving with snow chains
Observe the following precautions to reduce the risk of accidents.
Failing to do so may result in the vehicle being unable to be driven safely, and may
cause death or serious injury.
●Do not drive in excess of the speed limit specified for the tire chains being used,
or 30 mph (50 km/h), whichever is lower.
●Avoid driving on bumpy road surfaces or over potholes.
●Avoid sudden turns and braking, as use of chains may adversely affect vehicle
handling.
●Slow down sufficiently before entering a curve to ensure that vehicle control is
maintained.
NOTICE
■Repairing or replacing snow tires
Request repairs of and obtain replacement snow tires from Lexus dealers or legiti-
mate tire retailers.
This is because the removal and attachment of snow tires affects the operation of
the tire pressure warning valves and transmitters.
■Fitting tire chains
The tire pressure warning valves and transmitters may not function correctly when
tire chains are fitted.
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457
4-3. Do-it-yourself maintenance
4
Maintenance and care
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
■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
1 Summer tiresSummer 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.
2 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 sea-
son 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 handling performance compared wi th summer tires in highway driving.
3Snow 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 capac-
ity as the originally installed tires. Since your vehicle has radial tires as original
equipment, make sure your snow tires also have radial construction. Do not install
studded tires without first checking lo cal regulations for possible restriction.
Snow tires should be installed on all wheels. ( →P. 2 3 2 )
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. 577)
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467
4-3. Do-it-yourself maintenance
4
Maintenance and care
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
Wheels
If a wheel is bent, cracked or heavily corroded, it should be replaced.
Otherwise, the tire may separate from the wheel or cause loss of handling
control.
■ Wheel selection
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:
• Wheels of different sizes or types
• Used wheels
• Bent wheels that have been straightened
■ Aluminum wheel precautions
● Use only Lexus wheel nuts and wrenches designed for use with
your aluminum wheels.
● After 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 when bal-
ancing your wheels.
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5
When trouble arises
515
5-2. Steps to take in an emergency
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
■When the tire pressure warning light comes on
Check the tire inflation pressure and adjust to the appropriate level. Pushing the tire
pressure warning reset switch does not turn off the tire pressure warning light.
■The tire pressure warning light may turn on due to natural causes
The tire pressure warning light may turn on due to natural causes such as natural air
leaks or tire inflation pressure changes caused by temperature. In this case, adjust-
ing the tire inflation pressure will turn off the warning light (after a few minutes).
■When a tire is replaced with a spare tire
The compact spare tire is not equipped with the tire pressure warning valve and
transmitter. If a tire goes flat, the tire pressure warning light will not turn off even
though the flat tire is replaced with the spare tire. Replace the spare tire with the
repaired tire and adjust the proper tire inflation pressure. The tire pressure warning
light will turn off after a few minutes.
■If the tire pressure warning system is inoperative
The tire pressure warning system will be disabled in the following conditions:
(When the condition becomes normal, the system will work properly.)
●If tires not equipped with tire pressure warning valves and transmitters are used.
●If the ID code on the tire pressure warning valves and transmitters is not regis-
tered in the tire pressure warning computer.
●If the tire pressure warning select switch is set to a different tire setting.
●If the tire inflation pressure is 73 psi (500 kPa, 5.1 kgf/cm2 or bar) or higher.
The tire pressure warning system may be disabled in the following conditions:
(When the condition becomes normal, the system will work properly.)
●If electronic devices or facilities using similar radio wave frequencies are nearby.
●If a radio set at similar frequencies is in use in the vehicle.
●If a window tint that affects the radio wave signals is installed.
●If there is a lot of snow or ice on the vehicle, in particular around the wheels or
wheel housings.
●If non-genuine Lexus wheels are used. (Even if you use Lexus wheels, the tire
pressure warning system may not work properly with some types of tires.)
●If tire chains are used.
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578
6-1. Specifications
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
Tire ply composition and materials
Plies are layers of rubber-coated parallel cords. Cords are the strands
which form the plies in a tire.
Radial tires or bias-ply tires
A radial tire has RADIAL on the sidewall. A tire not marked RADIAL is a
bias-ply tire.
TUBELESS or TUBE TYPE
A tubeless tire does not have a tube and air is directly filled in the tire. A
tube type tire has a tube inside the ti re and the tube maintains the air pres-
sure.
Load limit at maximum cold tire inflation pressure ( →P. 583)
Maximum cold tire inflation pressure ( →P. 583)
This means the pressure to which a tire may be inflated.
Uniform tire quality grading
For details, see “Uniform Tire Quality Grading” that follows.
Summer tire or all season tire (→ P. 4 5 7 )
An all season tire has “M+S” on the sidewall. A tire not marked “M+S” is a
summer tire.
“TEMPORARY USE ONLY”
A compact spare tire is identified by the phrase “TEMPORARY USE
ONLY” molded into its sidewall. This tire is designed for temporary emer-
gency use only.
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579
6-1. Specifications
6
Vehicle specifications
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
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 thatthe tire conforms to applicable
Federal Motor Vehicle Safety
Standards.
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585
6-1. Specifications
6
Vehicle specifications
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
Tire related termMeaning
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 capacity
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 it by two
We a t h e r s i d eThe 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
GS450h_HV_U.book Page 585 Monday, April 27, 2009 10:10 AM