wheel Lexus GS450h 2008 Using the audio system / LEXUS 2008 GS450H (OM30A96U) Repair Manual

411
4-2. Maintenance
4
Maintenance and care
GS_HV_U
December 12, 2007 3:50 pm
Vehicle interior
ItemsCheck points
Accelerator pedal• Moves smoothly (without uneven pedal effort or catching)?
Transmission “Park” 
mechanism• Can the vehicle be hold securely on an incline with the shift lever in “P”?
Brake pedal
• Moves smoothly?
• Does it have appropriate clearance and correct amount of free play?
Brakes
• Pulls to one side when applied?
• Loss of brake effectiveness?
• Spongy feeling brake pedal?
• Pedal almost touches floor?
Head restraints• Move smoothly and lock securely?
Indicators/buzzers• Function properly?
Lights• Do all the lights come on?
• Headlights aimed correctly? ( P. 4 7 1 )
Pa r k i n g b r a ke
• Moves smoothly?
• Can hold the vehicle securely on an
incline?
Seat belts
• Does the seat belt system operate smoothly?
• Are the belts undamaged?
Seats• Do the seat controls operate properly?
Steering wheel
• Moves smoothly?
• Has correct free play?
• No strange noises?

412
4-2. Maintenance
GS_HV_U
December 12, 2007 3:50 pm
Vehicle exterior
ItemsCheck points
Doors/trunk• Operate smoothly?
Engine hood• The lock system works properly?
Fluid leaks• Is there any leakage after parking?
Ti r e
• Inflation pressure is correct?
• Tire surfaces not worn or dam-aged?
• Tires rotated according to the
maintenance schedule?
• Wheel nuts are not loose?
CAUTION
■If the hybrid system is running
Turn off the hybrid system and ensure that there is adequate ventilation before per-
forming maintenance checks.

436
4-3. Do-it-yourself maintenance
GS_HV_U
December 27, 2007 1:38 pm
Installing tire pressure warning valves and transmittersWhen replacing tires or wheels, tire pressure warning valves and trans-
mitters must also be installed.
When new tire pressure warning va lves and transmitters are installed,
new tire pressure warning valve and transmitter ID codes must be regis-
tered in the tire pressure warning computer and tire pressure warning
system must be initialized. Have tire pressure warning valve and transmit-
ter ID codes registered by your Lexus dealer. ( P. 4 3 8 )
Initializing the tire pressure warning system
■ The tire pressure warning system must be initialized in the following
circumstances:
● When rotating the tires on vehicles differing with front and rear tire
inflation pressures.
● When changing the tire inflation pressure by changing traveling
speed or load weight, etc.
When the tire pressure warning sys tem is initialized, the current tire
inflation pressure is set as the pressure benchmark.

439
4-3. Do-it-yourself maintenance
4
Maintenance and care
GS_HV_U
December 27, 2007 1:38 pm
■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.
■Replacing tires and wheels
If the ID code of the tire pressure warn ing valve and transmitter is not registered,
the tire pressure warning system will not work properly. After driving for 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 tread wears down below 0.16 in. (4 mm) on snow tires
The effectiveness of snow tires is lost.
■Low profile tires (245/40R18, P245/40R18 and 245/40ZR18 tires)
Generally, low profile tires will wear more rapidly and tire grip performance will be
reduced on snowy and/or icy roads when co mpared to standard tires. Be sure to
use snow tires or snow chains on snowy and/or icy roads and drive carefully at a
speed appropriate for road and weather conditions.
■Initializing the tire pressure warning system
Initialize the tires with the tire inflatio n pressure adjusted to the specified level.

440
4-3. Do-it-yourself maintenance
GS_HV_U
December 27, 2007 1:38 pm
■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. 4 4 5 , 5 5 6 ) .
■Tire types
1 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 in adequate 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 adequa te traction performance compared with
snow tires in heavy or loos e snow. Also, all 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 loca l regulations for possible restriction.
Snow tires should be installed on all wheels. ( P. 2 1 5 )

444
4-3. Do-it-yourself maintenance
GS_HV_U
December 27, 2007 1:38 pm
NOTICE
■Repairing or replacing tires, wheels and tire pressure warning valves and trans-
mitters
When removing or fitting the wheels, tire s or the tire pressure warning valve and
transmitter, contact your Lexus dealer as the tire pressure warning valve and trans-
mitter may be damaged if not handled correctly.
■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.
■Low profile tires (245/40R18, P245/40R18 and 245/40ZR18 tires)
Low profile tires may cause greater damage than usual to the tire wheel when
receiving impact from the road surface. Therefore pay attention to the following:
●Be sure to use proper tire inflation pressure. If tires are under-inflated, they may
be damaged more severely.
●Avoid hot holes, uneven pavement, curbs and other road hazards. Failure to do so
can lead to severe tire and wheel damage.
■If tire inflation pressures become low while driving
Do not continue driving, or your tires and/or wheels may be ruined.

448
4-3. Do-it-yourself maintenance
GS_HV_U
December 27, 2007 1:38 pm
CAUTION
■Proper inflation is critical to save tire performance
Keep your tires properly inflated. Otherwise, the following conditions may occur
and result in an accident causing death or serious injury.
●Excessive wear
●Uneven wear
●Poor handling
●Possibility of blowouts resulting from overheated tires
●Poor sealing of the tire bead
●Wheel deformation and/or tire separation
●A greater possibility of tire damage from road hazards
NOTICE
■When inspecting and adjusting tire inflation pressure
Be sure to reinstall the tire valve caps.
Without the valve caps, dirt or moisture co uld get into the valve and cause air leak-
age, which could result in an accident. If the caps have been lost, replace them as
soon as possible.

449
4-3. Do-it-yourself maintenance
4
Maintenance and care
GS_HV_U
December 27, 2007 1:38 pm
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 offset. 
Replacement wheels are available at your Lexus dealer.
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 wr enches designed for use with
your aluminum wheels.
● After rotating, repairing or chang ing 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.

450
4-3. Do-it-yourself maintenance
GS_HV_U
December 27, 2007 1:38 pm
■When replacing wheels
The wheels of your Lexus are equipped with tire pressure warning valves and trans-
mitters that allow the tire pressure warning system to provide advanced warning in
the event of a loss in tire inflation pressure. Whenever wheels are replaced, the tire
pressure warning valves and transmitters must be installed. ( P. 4 3 6 )
CAUTION
■When replacing wheels
●Do not use wheels that are a different size from those recommended in the
Owner’s Manual, as this may result in loss of handling control.
●Never use an inner tube in a leaking wheel which is designed for a tubeless tire.
Doing so may result in an accident, causing death or serious injury.
NOTICE
■Replacing tire pressure warning valves and transmitters
●Because tire repair or replacement may affect the tire pressure warning valves
and transmitters, make sure to have tires serviced by your Lexus dealer or other
qualified service shop. In addition, make sure to purchase your tire pressure
warning valves and transmitters at your Lexus dealer.
●Ensure that only genuine Lexus wheels are used on your vehicle. 
Tire pressure warning valves and transmitters may not work properly with non-
genuine wheels.

482
GS_HV_U
December 12, 2007 3:50 pm
5-1. Essential information
If your vehicle needs to be towed
Before towingThe following may indicate a problem with your transmission. Contact
your Lexus dealer before towing.
● The hybrid system is running, but the vehicle will not move.
● The vehicle makes an abnormal sound.
Emergency towing
If a tow truck is not available, in an emergency your vehicle may be tem-
porarily towed using a cable or ch ain secured to the emergency towing
eyelet. This should only attempted on hard, surfaced roads for short dis-
tances below 18 mph (30 km/h). 
A driver must be in the vehicle to s teer and operate the brakes. The vehi-
cle’s wheels, drive train, axles, steering and brakes must be in good condi-
tion.
If towing is necessary, we recommen d having your vehicle towed by your
Lexus dealer or a commercial towing service, using a lift-type truck or a flat
bed truck. 
Use a safety chain system for all towing , and abide by all state/provincial
and local laws.
If towing from the rear, the wheels and axle on the ground must be in good
condition.
If they are damaged, use a to wing dolly or flat bed truck.