Lexus GS430 2006 Scheduled Maintenance Guide / LEXUS 2006 GS430/GS300 FROM JAN. 2005 PROD. OWNER'S MANUAL (OM30649U)

ENGINE
520
FUEL PUMP SHUT OFF SYSTEM
The fuel pump shut off system stops supplying fuel to the
engine to minimize the risk of fuel leakage when the engine
stalls or an airbag inflates upon collision. To restart the engine
after the fuel pump shut off system activates, turn the engine
switch off once and start it.
CAUTION
Inspect the ground under the vehicle before restarting
the engine. If you find that liquid has leaked onto the
ground, it is the fuel system that has been damaged and
it is in need of repair. In this case, do not restart the
engine.
FACTS ABOUT ENGINE OILCONSUMPTION
Functions of engine oil
Engine oil has the primary function of lubricating and cooling
the inside of the engine, and plays a major role in maintaining
the engine in proper working order.
Engine oil consumption
It is normal that an engine should consume some engine
oil during normal engine operation. The causes of oil
consumption in a normal engine are as follows.
Oil is used to lubricate pistons, piston rings and cylinders.
A thin film of oil is left on the cylinder wall when a piston
moves downwards in the cylinder. High negative pressure
generated when the vehicle is decelerating sucks some of
this oil into the combustion chamber. This oil as well as
some part of the oil film left on the cylinder wall is burned by
the high temperature combustion gases during the
combustion process.
 Oil is also used to lubricate the stems of the intake valves.
Some of this oil is sucked into the combustion chamber
together with the intake air and is burned along with the fuel.
High temperature exhaust gases also burn the oil used to
lubricate the exhaust valve stems.

ENGINE
521
The amount of engine oil consumed depends on the
viscosity of the oil, the quality of the oil and the way the
vehicle is driven.
More oil is consumed under driving conditions such as high
speeds and frequent acceleration and deceleration.
A new engine consumes more oil, since its pistons, piston rings
and cylinder walls have not become conditioned.
Oil consumption: Max. 1.0 L per 1000 km (1.1 qt./600 miles,
0.9 lmp·qt./600 miles).
When judging the amount of oil consumption, keep in
mind that the oil may have become diluted, making it
difficult to judge the true level accurately.
For example, if a vehicle is used for repeated short trips and
consumes a normal amount of oil, the dipstick may not show
any drop in the oil level at all, even after 1000 km (600 miles)
or more. This is because
the oil is gradually becoming diluted
with fuel or moisture, making it appear that the oil level has not
changed.
The diluting ingredients evaporate out when the vehicle is then
driven at high speeds, as on an expressway, making it appear
that oil is excessively consumed after driving at high speeds.
Importance of engine oil level check
One of the most important points in proper vehicle
maintenance is to keep the engine oil at the optimum level so
that oil function will not be impaired. Therefore, it is essential
that the oil level be checked regularly. Lexus recommends that
the oil level be checked every time you refuel the vehicle.
NOTICE
Failure to check the oil level regularly could lead to
serious engine trouble due to insufficient oil.
For detailed information on oil level check, see ”Checking the
engine oil level” on page 522.

ENGINE
522
USED ENGINE OIL
CAUTION
Used engine oil contains potentially harmful
contaminants which may cause skin disorders such
as inflammation or skin cancer, so care should be
taken to avoid prolonged and repeated contact with
it. To remove used engine oil from your skin, wash
thoroughly with soap and water.
 Do not leave used oil within the reach of children.
 Dispose of used oil and used oil filters only in a safe
and acceptable manner. Do not dispose of used oil
and used oil filters in household trash, in sewers or
onto the ground. Call your Lexus dealer or a service
station for information concerning recycling or
disposal.
CHECKING THE ENGINE OIL LEVEL
G62001
 GS430
G62002
GS300
With the engine at operating temperature and turned off,
check the oil level on the dipstick.

ENGINE
523
1. To get a correct reading, the vehicle should be on level
ground. After turning off the engine, wait a few minutes for the
oil to drain back into the bottom of the engine.
2. Pull the dipstick out, hold a rag under the end and wipe it
clean.
3. Reinsert
the dipstick and push it in as far as it will go, or the
reading will not be correct.
G62006
 GS430
1
Add oil 2O.K. 3Too full
G62005
GS300 (twowheel drive models)
1
Add oil 2O.K. 3Too full

ENGINE
524
G62006
GS300 (fourwheel drive models)
1
Add oil 2O.K. 3Too full
4. Pull the dipstick out and look at the oil level while holding a
rag under the end. If it is between the full level mark (
5 ) and
the low level mark ( 4 ), it is O.K.
NOTICE
Be careful not to drop engine oil on the vehicle
components.
G62003
GS430 GS300
If the oil level is below or only slightly above the low level
mark, add engine oil of the same type as already in the
engine.
Remove the oil filler cap and add engine oil a little at a time,
checking the dipstick. We recommend that you use a funnel
when adding oil. The approximate quantity of oil needed to
raise the level between low and full on the dipstick is indicated
as follows:
1.5 L (1.6 qt., 1.3 lmp. qt.)
For the engine oil capacity, see “Specifications” on pages 512
and 515.
When the level reaches within the correct range, return the
filler cap and turn the cap clockwise until you hear a click.

ENGINE
525
NOTICE
Be careful not to spill engine oil on the vehicle
components.
 Avoid overfilling, or the engine could be damaged.
 Check the oil level on the dipstick once again after
adding the oil.
Engine oil selection
“Toyota Genuine Motor Oil” is used in your Lexus vehicle. Use
Lexus approved “Toyota Genuine Motor Oil” or equivalent to
satisfy the following grade and viscosity.
Oil grade: API grade SL “Energy −Conserving” or ILSAC
multigrade engine oil.
Recommended viscosity: 5W−30
62L042
Outside temperature
SAE 5W30 is the best choice for good fuel economy, and
good starting in cold weather.
If SAE 5W30 is not available, SAE10W30 may be used.
However, it should be replaced with 5W30 at the next oil
change.

ENGINE
526
Oil identification marks
62L038
API Service Symbol ILSAC Certification Mark
Either or both API registered marks are added to some oil
containers to help you select the oil you should use.
 The API Service Symbol is located anywhere on the outside
of the container.
The top portion of the label shows the oil quality by API
(American Petroleum Institut e) designation such as SL.
The center portion of the label shows the SAE viscosity
grade such as SAE 5W −30. ”Energy− Conserving”, shown
in the lower portion, indicates that the oil has fuel −saving
capabilities.
 The ILSAC (International L ubricant Standardization and
Approval Committee) Certification Mark is displayed on the
front of the container. To ensure excellent lubrication for your engine, “Toyota
Genuine Motor Oil” is available, which has been specifically
tested and approved for all Lexus engines.
Please contact your Lexus deal
er for further details about
“Toyota Genuine Motor Oil”.

ENGINE
527
CHECKING THE ENGINE COOLANTLEVEL
G62007
GS430
1
Reservoir cap 2“FULL” line 3“LOW” line
G62008
GS300
1
Reservoir cap 2“FULL” line 3“LOW” line Look at the seethrough coolant reservoir when the
engine is cold. The coolant level is satisfactory if it is
between the”FULL” and ”LOW” lines on the reservoir. If
the level is low, add the coolant. (For the coolant type, see
“Coolant type selection” described below.)
The coolant level in the reservoir will vary with engine
temperature. However, if the level is on or below the ”LOW”
line, add coolant. Bring the level up to the ”FULL” line.
If the coolant level drops within a short time after replenishing,
there
may be a leak in the system. V isually check the radiator,
hoses, engine coolant filler cap, radiator cap and drain cock
and water pump.
If you can find no leak, have your Lexus dealer test the cap
pressure and check for leaks in the cooling system.
CAUTION
To prevent burning yourself, do not remove the radiator
cap when the engine is hot.

ENGINE
528
Coolant type selection
Use of improper coolants may damage your engine cooling
system.
Only use ”Toyota Super Long Life Coolant” or similar high
quality ethylene glycol based non−silicate, non −amine,
non− nitrite, and non −borate coolant with long −life hybrid
organic acid technology. (Coolant with long −life hybrid organic
acid technology is a combination of low phosphates and
organic acids.)
For the U.S.A.—“Toyota Super Long Life Coolant” is a mixture
of 50% coolant and 50% deionized water. This coolant
provides protection down to about −35C (− 31F).
For Canada—“Toyota Super Long Life Coolant” is a mixture of
55% coolant and 45% deionized water. This coolant provides
protection down to about −42C (− 44F).
NOTICE
Do not use plain water alone.
Lexus recommends “Toyota Super Long Life Coolant,” which
has been tested to ensure that it will not cause corrosion nor
result in malfunction of your engine coolant system with proper
usage. “Toyota Super Long Life Coolant” is formulated with
long−life hybrid organic acid technology and has been
specifically designed to avoid engine cooling system
malfunction on Lexus vehicles.
Please contact your Lexus dealer for further details.

ENGINE
529
CHECKING THE RADIATOR ANDCONDENSER
If either of the above parts are extremely dirty or you are not
sure of their condition, take your vehicle to your Lexus dealer.
CAUTION
To prevent burning yourself , be careful not to touch the
radiator or condenser when the engine is hot.
NOTICE
To prevent damage to the radiator and condenser, do
not perform the work by yourself.
SPARK PLUGS
62R031c
GS430
Your engine is fitted with iridiumtipped spark plugs.
NOTICE
Use only iridiumtipped spark plugs and do not adjust
gaps for your engine performance and smooth
drivability.