tire size Lexus GS350 2015 TIPS FOR THE NAVIGATION SYSTEM / LEXUS 2015 GS350 OWNERS MANUAL (OM30E15U)

15Pictorial index
GS350_OM_OM30E15U_(U)
Windshield wipers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 202
Precautions against winter season . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 284
To prevent freezing (windshield wiper de-icer)
* . . . . . . . . . . . . . . . . . . . . P. 327
Precautions against car wash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 378
Fuel filler door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 210
Refueling method. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 210
Fuel type/fuel tank capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 538
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 410
Tire size/inflation pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 543
Winter tires/tire chain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 284
Checking/rotation/tire pressure warning system. . . . . . . . . . . . . . . . . . . . .P. 410
Coping with flat tires. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 504
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 394
Opening . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 394
Engine compartment cover. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 398
Engine oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 5 3 8
Coping with overheat. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 529
Warning messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 487
Headlights/parking lights/daytime running ligh ts . . . . . . . . . . . . . . . . . . . P. 196
Fog lights
* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 201
Turn signal lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 190
Tail lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 196
Stop lights
Hill-start assist control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 257
License plate lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 19 6
Back-up lights
Shifting the shift lever to R . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 184
Side marker lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 19 6
4
5
6
7
Light bulbs of the exterior lights for driving
(Replacing method: P. 444, Watts: P. 545)
*: If equipped
8
9
10
11
12
13
14
15

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4-5. Using the driving support systems
CAUTION
■Replacing tires
Make sure that all tires are of the specified size, brand, tread pattern and total load
capacity. In addition, make sure that the tires are inflated to the recommended tire
inflation pressure level.
The ABS, TRAC and VSC systems will not function correctly if different tires are
installed on the vehicle.
Contact your Lexus dealer for further information when replacing tires or wheels.
■Handling of tires and the suspension
Using tires with any kind of problem or modifying the suspension will affect the
driving assist systems, and may cause a system to malfunction.

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4-6. Driving tips
Winter driving tips
●Use fluids that are appropriate to the prevailing outside temperatures. • Engine oil
• Engine coolant
• Washer fluid
●Have a service technician inspec t the condition of the battery.
●Have the vehicle fitted with four sno w tires or purchase a set of tire
chains for the rear tires.
*
Ensure that all tires are the specified size and brand, and that chains match the
size of the tires.
*: Tire chains cannot be mounted on vehicles with front and rear tires of differing
sizes and vehicles with LDH and 19-inch tires.
Carry out the necessary preparati ons and inspections before driving
the vehicle in winter. Always drive the vehicle in a manner appropriate
to the prevailing weather conditions.
Preparation for winter

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4-6. Driving tips
Vehicles with front and rear tires of the same size except for the vehi-
cles with LDH and 19 inch tires
Use the correct tire chain size when mounting the tire chains.
Chain size is regulated for each tire size. Side chain
(0.12 in. [3 mm] in diameter)
Cross chain
(0.16 in. [4 mm] in diameter)
Vehicles with front and rear tires of differing sizes and vehicles with
LDH and 19 inch tires
Tire chains cannot be mounted.
Snow tires should be used instead.
Regulations regarding the use of tire chains vary depending on location
and type of road. Always check loca l regulations before installing chains.
Selecting tire chains
1
2
Regulations on the use of tire chains

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4-6. Driving tips
CAUTION
■Driving with snow tires
Observe the following precautions to reduce the risk of accidents.
Failure to do so may result in a loss of vehicle control and cause death or serious
injury.
●Use tires of the specified size.
●Maintain the recommended level of air 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.
●Do not use LKA (Lane-Keeping Assist) system.
■Driving with tire chains (vehicles with front and rear tires of the same size except
for the vehicles with LDH and 19 inch tires)
Observe the following precautions to reduce the risk of accidents.
Failure 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 acceleration, abrupt steering, sudden braking and shifting opera-
tions that cause sudden engine braking.
●Slow down sufficiently before entering a curve to ensure that vehicle control is
maintained.
●Do not use LKA (Lane-Keeping Assist) system.

GS350_OM_OM30E15U_(U)
2894-6. Driving tips
4
Driving
NOTICE
■Repairing or replacing snow tires
Request repairs or replacement of snow tires from Lexus dealers or legitimate 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 (vehicles with front an d rear tires of the same size except for
the vehicles with LDH and 19 inch tires)
The tire pressure warning valves and transmitters may not function correctly when
tire chains are fitted.
■When standing the windshield wipers up
Raise the wipers in line with the windshield. ( P. 2 8 7 )
Failure to do so may result in dama ge to the wipers and/or the hood.

GS350_OM_OM30E15U_(U)
4116-3. Do-it-yourself maintenance
6
Maintenance and care
Vehicles with front and rear tires of the same size
Rotate the tires in the order
shown.
To equalize tire wear and extend tire
life, Lexus recommends that tire rota-
tion is carried out at the same interval
as tire inspection.
Do not fail to initialize the tire pressure
warning system after tire rotation.
Vehicles with front and rear tires of differing sizes
Tires cannot be rotated.
Tire rotation
Front

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6-3. Do-it-yourself maintenance
◆Registering ID codes
The tire pressure warning valve and transmitter is equipped with a
unique ID code. When replacing a tire pressure warning valve and
transmitter, it is necessary to register the ID code. Have the ID code
registered by your Lexus dealer.
■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,
and bulges indicating internal damage
●A tire goes flat repeatedly or cannot be properly repaired due to the size or loca-
tion of a cut or other damage
If you are not sure, consul t with your Lexus dealer.
■Replacing tires and wheels
If the ID code of the tire pressure warning valve and transmitter is not registered, the
tire pressure warning system will not work properly. After driving for about 20 min-
utes, the tire pressure warning light blinks for 1 minute and stays on to indicate a sys-
tem malfunction.
■Tire life
Any tire over 6 years old must be checked by a qualified technician even if it has sel-
dom or never been used or damage is not obvious.
■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.
■When rotating the tires (vehicles with the tire inflation pressure display function)
Make sure that the engine switch is off. If the tires are rotated while the engine switch
is in IGNITION ON mode, the tire posi tion information will not be updated.
If this accidentally occurs, either turn th e engine switch to off and then to IGNITION
ON mode, or initialize the system after checking that the tire pressure is properly
adjusted.

GS350_OM_OM30E15U_(U)
4156-3. Do-it-yourself maintenance
6
Maintenance and care
■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. ( P. 2 8 6 )
■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 in adequate for driving on snow-covered or
icy roads. For driving on snow-covered road s 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 seas on 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 th e 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. 2 8 4 )
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 4 9 )

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6-3. Do-it-yourself maintenance
■If the tread on snow tires wears down below 0.16 in. (4 mm)
The effectiveness of the tires as snow tires is lost.
■Situations in which the tire pressure warning system may not operate properly
●In the following cases, the tire pressure warning system may not operate properly.
• If non-genuine Lexus wheels are used.
• A tire has been replaced with a tire that is not an OE (Original Equipment) tire.
• A tire has been replaced with a tire that is not of the specified size.
• Tire chains etc. are equipped.
• Lock nuts are equipped.
• An auxiliary-supported run- flat tire is equipped.
• If a window tint that affects the radio wave signals is installed.
• If there is a lot of snow or ice on the vehicle, particularly around the wheels or wheel housings.
• If the tire inflation pressure is extremely higher than the specified level.
●Performance may be affected in the following situations.
• Near a TV tower, electric power plant, gas station, radio station, large display,
airport or other facility that generates strong radio waves or electrical noise
• When carrying a portable radio, cellular phone, cordless phone or other wire- less communication device
Vehicles with the tire inflation pressure display function: If tire position information
is not correctly disp layed due to the radio wave conditions, the display may be
corrected by driving and changing the radio wave conditions.
●When the vehicle is parked, the time taken for the warning to start or go off could
be extended.
●When tire inflation pressure declines rapi dly for example when a tire has burst, the
warning may not function.
■The initialization operation
●Make sure to carry out initialization after adjusting the tire inflation pressure.
Also, make sure the tires are cold before carrying out initialization or tire inflation
pressure adjustment.
●If you have accidentally turned the engine sw itch off during initialization, it is not
necessary to press the reset switch again as initialization will restart automatically
when the engine switch has been turned to IGNITION ON mode for the next time.
●If you accidentally press the reset switch when initialization is not necessary, adjust
the tire inflation pressure to the specified level when the tires are cold, and conduct
initialization again.