2008 Lexus GS460 tire pressure

518
5-2. Steps to take in an emergency
GS_G_U
May 13, 2008 5:14 pm
Firmly tighten each nut two or
three times in the order shown in
the illustration.
Tightening torque:
76 ft•lbf (103 N•m, 10.5 kgf•m)
Stow the flat tire, tire jack and all tools.
STEP4
■If you have a flat rear tire on a road covered with snow or ice
Install the compact spare tire on the front of the vehicle. Perform the following steps
and fit tire chains to the rear tires.
Replace a front tire with the compact spare tire.
Replace the flat rear tire with the tire removed from the front of the vehi-
cle.
Fit tire chains to the rear tires.
■After completing the tire change
The tire pressure warning system must be reset. ( P. 4 2 2 )
STEP5
STEP1
STEP2
STEP3

5
When trouble arises
521
5-2. Steps to take in an emergency
GS_G_U
May 13, 2008 5:14 pm
NOTICE
■Do not drive the vehicle with a flat tire
Do not continue driving with a flat tire.
Driving even a short distance with a flat tire can damage the tire and the wheel
beyond repair.
■Be careful when driving over bumps with the compact spare tire installed on the
vehicle
The vehicle becomes lower when driving with the compact spare tire compared to
when driving with standard tires. Be careful when driving over uneven road sur-
faces.
■Driving with tire chains and the compact spare tire
Do not fit tire chains to the compact spare tire. 
Tire chains may damage the vehicle body and adversely affect driving performance.
■When replacing the tires
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.

522
5-2. Steps to take in an emergency
GS_G_U
May 13, 2008 5:14 pm
If you have a flat tire (Vehicles with run-flat tires)
■In some condition (such as at high temperatures)
You can not continue driving for up to 100 miles (160 km).
■If you cannot distinguish between th e standard tires and run-flat tires
Consult your Lexus dealer.
■For the detailed information on run-flat tires
See the tire warranty book.
NOTICE
■When replacing the tires
Have the tires replaced by the nearest Lexus dealer or authorized tire dealer. The
tire pressure warning valves and transmitters will be affected by the installation or
removal of tires.
■To avoid damaging the tire pressu re warning valves and transmitters
Do not use liquid sealants on flat tires.
Take your vehicle to the nearest Lexus dealer or authorized tire dealer as
soon as possible.
■ Run-flat tires (A “RFT” or “DSST” mark is molded on the sidewall)
You can continue driving a vehi-
cle with run-flat tires even if any
tire goes flat.
It is able to run for a maximum of
100 miles (160 km) at a speed
below 55 mph (90 km/h) after
the tire pressure warning light
comes on. (P. 4 9 0 )

5
When trouble arises
531
5-2. Steps to take in an emergency
GS_G_U
May 13, 2008 5:14 pm
■Starting the engine when the 12 volt battery is discharged
The engine cannot be started by push-starting.
■To prevent 12 volt battery discharge
●Turn off the headlights and the audio system while the engine is turned off.
●Turn off any unnecessary electrical compon ents when the vehicle is running at a
low speed for an extended period, such as in heavy traffic, etc.
■When the 12 volt battery is removed or discharged
The following systems must be initialized.
●Tire pressure warning system (P. 4 2 2 )
●Intuitive parking assist (P. 5 0 7 )
CAUTION
■Avoiding battery fires or explosions
Observe the following precautions to prevent accidentally igniting the flammable
gas that may be emitted from the battery.
●Make sure the jumper cable is connected to the correct terminal and that it is not
unintentionally in contact with any pa rt other than the intended terminal.
●Do not allow the jumper cables to come into contact with the “+” and “-” termi-
nals.
●Do not allow open flame or use matches, cigarette lighters or smoke near the
battery.
Maintain the engine speed on th e second vehicle and turn the
“ENGINE START STOP” switch to the IGNITION ON mode,
then start the vehicle’s engine.
Once the vehicle’s engine ha s started, remove the jumper
cables in the exact reverse ord er in which they were con-
nected.
Once the engine starts, have the ve hicle checked at your Lexus dealer
as soon as possible.STEP5
STEP6

550
6-1. Specifications
GS_G_U
May 13, 2008 5:14 pm
Tires and wheelsTy p e A
Ti r e s i z e245/40R18 93Y, P245/40R18 93V, 
245/40ZR18, T155/70D17 110M (spare)
Front and rear tire inflation 
pressure
(Recommended cold tire inflation
pressure)
Driving under normal conditions 
33 psi (230 kPa, 2.3 kgf/cm2 or bar)
Driving at high speeds above 100 mph (160
km/h) (in countries where such speeds are per-
mitted by law) Add 9 psi (60 kPa, 0.6 kgf/cm
2 or bar) to the
front tires and rear tires. Never exceed the
maximum cold tire inflation pressure indicated
on the tire sidewall.
Spare tire inflation pressure 
(Recommended cold tire inflation
pressure)
60 psi (420 kPa, 4.2 kgf/cm2 or bar)
Wheel size18  8 J, 17  4T (spare)
Wheel nut torque76 ft•lbf (103 N•m, 10.5 kgf•m)

551
6-1. Specifications
6
Vehicle specifications
GS_G_U
May 13, 2008 5:14 pm
Type B
Ti r e s i z e225/50R17 94W, P225/50R17 93V,
T155/70D17 110M (spare)
Front and rear tire inflation 
pressure
(Recommended cold tire inflation
pressure)
Driving under normal conditions 
33 psi (230 kPa, 2.3 kgf/cm2 or bar)
Driving at high speeds above 100 mph (160
km/h) (in countries where such speeds are per-
mitted by law) Add 7 psi (50 kPa, 0.5 kgf/cm
2 or bar) to the
front tires and rear tires. Never exceed the
maximum cold tire inflation pressure indicated
on the tire sidewall.
Spare tire inflation pressure 
(Recommended cold tire inflation
pressure)
60 psi (420 kPa, 4.2 kgf/cm2 or bar)
Wheel size17  7 1 /2 J, 17  4T (spare)
Wheel nut torque76 ft•lbf (103 N•m, 10.5 kgf•m)

557
6-1. Specifications
6
Vehicle specifications
GS_G_U
May 13, 2008 5:14 pm
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 tire and the tube maintains the air pres-
sure.
Load limit at maximum cold tire inflation pressure ( P. 5 6 2 )
Maximum cold tire inflation pressure ( P. 5 6 2 )
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 2 6 )
An all season tire has “M+S” on the si dewall. 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.

562
6-1. Specifications
GS_G_U
May 13, 2008 5:14 pm
■Temperature A, B, C
The temperature grades are A (the highest), B, and C, representing
the tire’s resistance to the generation of heat and its ability to dissipate
heat when tested under controlled conditions on a specified indoor
laboratory test wheel.
Sustained high temperature can cause the material of the tire to degenerate
and reduce tire life, and excessive temperature can lead to sudden tire fail-
ure.
The grade C corresponds to a level of performance which all passenger car
tires must meet under the Federal Mo tor Vehicle Safety Standard No. 109.
Grades B and A represent higher levels of performance on the laboratory
test wheel than the minimum required by law.
Warning: The temperature grades for this tire are established for a tire that
is properly inflated and not overloaded. 
Excessive speed, underinflation, or excess ive loading, either separately or in
combination, can cause heat buildup and possible tire failure.
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