2008 Lexus GX470 Owner's Manual

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4-3. Do-it-yourself maintenance
Tires
Replace or rotate tires in accordance with maintenance schedules and
treadwear.
■Checking tires
New tread
Treadwear indicator
Worn tread
The location of treadwear indi-
cators is shown by the “TWI” or
“∆ ” marks, etc., molded on the
sidewall of each tire.
Check spare tire condition and
inflation pressure if not rotated.
■ Tire rotation
Rotate the tires in the order
shown.
Lexus recommends tire rotation
in accordance with the mainte-
nance schedule to equalize tire
wear and extend tire life.
■The tire pressure warning system
Your Lexus is equipped with a tire pressure warning system that uses
tire pressure warning valves and transmitters to detect low tire infla-
tion pressure before serious problems arise. ( →P. 385)
Front

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Maintenance and care
Installing tire pressure warning 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 tire pressure warning valve and transmitter ID codes must be regis-
tered in the tire pressure warning computer.
Registering and se lecting ID codes
■ Registering ID codes
2 sets of tire pressure warning valve and transmitter ID codes can be
registered. Once a second set of tires (winter tires etc.) is registered at
“2nd”, you can switch between tire set settings simply by pressing the
tire pressure warning select switch.
There are 2 settings:
“MAIN” position: The ID code of the tire pressure warning valve and
transmitter on the tires originally installed on the vehicle is registered.
“2nd” position: The code is not registered. When you replace a new set
of tires, purchase tire pressure warning valves and transmitters from
your Lexus dealer and have the new ID code registered by your Lexus
dealer.

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4-3. Do-it-yourself maintenance
■Selecting ID codes
When replacing tires, make sure to select the ID code set that matches
the new tire set. If the tire pressure select switch is set to the wrong set-
ting, the tire pressure warning system will not operate properly. After
driving for about 20 minutes, the tire pressure warning light comes on
after blinking for 1 minute to indicate a system malfunction.
“MAIN”
“2nd”
■When to replace your vehicle’s tires
Tires should be replaced if:
●You have tire damage such as cuts, splits, cracks deep enough to expose the
fabric or bulges indicating internal damage
●A tire goes flat repeatedly or cannot be properly repaired due to the size or
location of a cut or other damage
If you are not sure, consult with your Lexus dealer.

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4-3. Do-it-yourself maintenance
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Maintenance and care
■Replacing tires and wheels
If the ID code is not registered, the system will not work properly. After about 20
minutes, the tire pressure warning light comes on after blinking for 1 minute to indi-
cate a system malfunction.
■Tire life
Any tire over 6 years old must be checked by a qualified technician even if they
have seldom or never been used or damage is not obvious.
■If the treadwears down below 0.16 in. (4 mm) on snow tires
The effectiveness of snow tires is lost.
■Maximum load of tire
Check that the maximum load of the replaced tire is greater than 1 /2 of the Gross
Axle Weight Ratings (GAWR) of either the front axle or the rear axle, whichever is
greater.
As for the maximum load of the tire, see the load limit at maximum cold tire inflation
pressure mentioned on the sidewall of the tire, and as for the Gross Axle Weight
Ratings (GAWR), see the Certification Label. (
→P. 3 4 3 , 4 2 4 ) .

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4-3. Do-it-yourself maintenance
’■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, al l season tires fall short in acceleration
and handling performance compared with 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 local regulations for possible restriction.
Snow tires should be installed on all wheels. ( →P. 1 76 )
■Routine tire inflation pressure checks
The tire pressure warning system does not replace routine tire inflation pressure
checks. Make sure to check tire inflation pressure as part of your routine of daily
vehicle checks.
■If the tire pressure select switch is set to the wrong tire setting
The system will not work properly. After driving for about 20 minutes, the tire pres-
sure warning light comes on after blinking for 1 minute to indicate a system malfunc-
tion.

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Maintenance and care
■Tire pressure warning system certificationFor vehicles sold in the U.S.A.
NOTE:
This device complies with Part 15 of the FCC Rules. Operation is subject to the fol-
lowing two conditions: (1) this device may not cause harmful interference, and (2)
this device must accept any interference received, including interference that may
cause undesired operation.
NOTICE:
This equipment has been tested and found to comply with the limits for a Class B
digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to
provide reasonable protection against harmful interference in a residential installa-
tion. This equipment generates, uses and can radiate radio frequency energy and, if
not installed and used in accordance with the instructions, may cause harmful inter-
ference to radio communications. However, there is no guarantee that interference
will not occur in a particular installation. If this equipment does cause harmful inter-
ference to radio or television reception, which can be determined by turning the
equipment off and on, the user is encouraged to try to correct the interference by
one or more of the following measures:
●Reorient or relocate the receiving antenna.
●Increase the separation between the equipment and receiver.
●Connect the equipment into an outlet on a circuit different from that to which
the receiver is connected.
●Consult the dealer or an experienced radio/TV technician for help.
FCC WARNING:
Changes or modifications not expressly approved by the party responsible for
compliance could void the user’s authority to operate the equipment. For vehicles sold in Canada
NOTE:
Operation is subject to the following two conditions: (1) this device may not cause
interference, and (2) this device must accept any interference, including interfer-
ence that may cause undesired operation of the device.

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4-3. Do-it-yourself maintenance
CAUTION
■When inspecting or replacing tires
Observe the following precautions to prevent accidents. Failure to do so may cause
damage to parts of the drive train, as well as dangerous handling characteristics,
which may lead to fatal or injury accidents.
●Do not mix tires of different makes, models, tread patterns or treadwear.
●Do not use tire sizes other than those recommended by Lexus.
●Do not mix radial, bias-belted, or bias-ply tires.
●Do not mix summer, all season and winter tires.
NOTICE
■Repairing or replacing tires, wheels and tire pressure warning valves and trans-
mitters
●When removing or fitting the wheels, tires or the tire pressure warning valve and
transmitter, contact your Lexus dealer as the tire pressure warning valve and
transmitter may be damaged if not handled correctly.
●When replacing tires, make sure also to replace the tire pressure warning valve
and transmitter grommets.
■To avoid damaging the tire pressu re warning valves and transmitters
Do not use liquid sealants on flat tires.
■Driving on rough roads
Take particular care when driving on roads with loose surfaces or potholes.
These conditions may cause losses in tire inflation pressure, reducing the cushion-
ing ability of the tires. In addition driving on rough roads may cause damage to the
tires themselves, as well as the vehicle’s wheels and body.
■If tire inflation pressures become low while driving
Do not continue driving, or your tires and/or wheels may be ruined.

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Maintenance and care
Tire inflation pressure
■Tire inflation pressure
The recommended cold tire inflation pressure and tire size is dis-
played on the tire and loading information label. ( →P. 4 1 9 )