Lexus GS300 2003 Engine

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.
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 ºChecking the
engine oil levelº on page 260.

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
62G005d

GS430
GS300
With the engine at operating temperature and turned off,
check the oil level on the dipstick.
1. To get a true reading, the vehicle should be on a level spot.
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.

62g031

GS430 1Add oil 2O.K. 3Too full
62g032

GS300 1Add 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 line ( 5
) and the
low line ( 4
), it is O.K.
NOTICE
Be careful not to drop the engine oil on the vehicle
components.

62G007e

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 fill
between the low level mark and the full level mark on the
dipstick is indicated below for reference.
When the level reaches within the correct range, return the
filler cap and turn the cap clockwise until you hear a click.
Oil quantity. L (qt., lmp. qt.) 1.8 (1.9, 1.6)
NOTICE
Be careful not to spill the 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
ªToyota Genuine Motor Oilº is filled in your Lexus vehicle. Use
Lexus approved ªToyota Genuine Motor Oilº or equivalent to
satisfy the following grade and viscosity.
Oil grade: API grade SL ªEnergy±Conservingº or ILSAC
multigrade engine oil.
Recommended viscosity: 5W±30
62sa08
Temperature range anticipated before next oil change
SAE 5W±30 is the best choice for good fuel economy, and
good starting in cold weather.
If SAE is not available, SAE10W±30 may be used.
However, it should be replaced with 5W±30 at the next oil
change.
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 Institute) designation such as SL.
The center portion of the label shows the SAE viscosity
grade such as SAE 5W±30. ºEnergy±Conservingº, shown
in the lower portion, indicates that the oil has fuel±saving
capabilities.
The ILSAC (International Lubricant Standardization and
Approval Committee) Certification Mark is displayed on the
front of the container.

To ensure excellent performance for your engine, the ªToyota
Genuine Motor Oilº range is available, which has been
specifically tested and approved for all Lexus engines.
Please contact your Lexus dealer for further details of the
ªToyota Genuine Motor Oilº range.CHECKING THE ENGINE COOLANT
LEVEL
62G028

GS430 1Reservoir cap 2Upper line 3Lower line
62G004±1

GS300 1Reservoir cap 2Upper line 3Lower line

Look at the see±through coolant reservoir when the
engine is cold. The coolant level is satisfactory if it is
between theºFULLº and ºLOWº lines on the reservoir. If
the level is low, add ethylene±glycol type coolant for a
proper corrosion protection of aluminum components.
The coolant level in the reservoir will vary with engine
temperature. However, if the level is on or below the ºLOWº
line, add coolant. Bring the level up to the ºFULLº line.
Always use ethylene±glycol type coolant for a proper corrosion
protection of aluminum components. See information in the
next column.
If the coolant level drops within a short time after replenishing,
there may be a leak in the system. Visually 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.
Coolant type selection
Use of improper coolants may damage your engine cooling
system. Your coolant must contain ethylene±glycol type
coolant for a proper corrosion protection of your engine that
contains aluminum components. We have used ªToyota
Genuine Long Life Coolantº in your Lexus vehicle. In order to
avoid technical problems, we strongly recommend using
ªToyota Genuine Long Life Coolantº or equivalent.
In addition to preventing freezing and subsequent damage to
the engine, this type of coolant will also prevent corrosion.
Further supplemental inhibitors or additives are neither
needed nor recommended.
Read the coolant container for information on freeze
protection. Follow the manufacturer's directions for how much
to mix with plain water (preferably demineralized water or
distilled water). The total capacity of the cooling system is
given on page 252 or 255.
We recommend to use 50% solution for your Lexus, to provide
protection down to about ±35C (±31F). When it is extremely
cold, to provide protection down to about ±50C (±58F), 60%
solution is recommended. Do not use more than 70% solution
for better coolant performance.
NOTICE
Do not use alcohol type antifreeze or plain water alone.

The engine cooling system is integral to maximizing
performance of your Lexus vehicle. In line with this, it is
strongly recommended that you use ªToyota Genuine Long
Life Coolantº for protecting the system, as it is an
ethylene±glycol based premium antifreeze coolant with
excellent corrosion protection properties that has been
specifically formulated for use in Lexus vehicles.
Please contact your Lexus dealer for further details of the
ªToyota Genuine Long Life Coolantº range.CHECKING THE RADIATOR AND
CONDENSER
If either of the above parts are extremely dirty or you are not
sure of their condition, take your vehicle to 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 iridium±tipped spark plugs.
NOTICE
Use only iridium±tipped spark plugs and do not adjust
gaps for your engine performance and smooth
drivability.
62g021a

GS300
Your engine is fitted with the designated iridium±tipped
spark plugs.
NOTICE
Use the designated iridium±tipped spark plugs and do
not adjust gaps for your engine performance and
smooth drivability.