2001 Lexus GS300 Engine

ENGINE
251
FACTS ABOUT ENGINE OIL
CONSUMPTION
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.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.

ENGINE
252
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 253.
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.

ENGINE
253
CHECKING THE ENGINE OIL LEVEL
62G005c

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 out the dipstick, and wipe it clean with a rag.
3. Reinsert the dipstick and push it in as far as it will go, or the
reading will not be correct.
62G006±1
1Add oil 2O.K. 3Too full
4. Pull the dipstick out and look at the oil level on the end. If
it is between the low level mark ( 4
) and the full level mark
( 5
), it is O.K.

ENGINE
254
62G007d

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. 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
Avoid overfilling, or the engine could be damaged.
Check the oil level on the dipstick once again after
adding the oil.
Engine oil selection
Use API SJ, ºEnergy±Conservingº multigrade engine oil or
ILSAC multigrade engine oil.
Recommended viscosity (SAE):
62L005±1
Temperature range anticipated before next oil change
SAE 5W±30 is the best choice for your vehicle, for good
fuel economy, and good starting in cold weather.
If you use SAE 10W±30 engine oil in extremely low
temperatures, the engine may become difficult to start, so
SAE 5W±30 engine oil is recommended.

ENGINE
255
Oil identification marks
62L006±1

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 SJ.
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.
CHECKING THE ENGINE COOLANT
LEVEL
62G004±1

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.

ENGINE
256If 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. Use ºToyota 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 245 or 247.
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.

ENGINE
257
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.

ENGINE
258