1999 Lexus GS300 engine oil

SECTION 6 ± 2
378
SERVICE PROCEDURES AND
SPECIFICATIONS
Engine
Specifications (GS400) 379. . . . . . . . . . . . . . . . . . . . . . . .
Specifications (GS300) 383. . . . . . . . . . . . . . . . . . . . . . . .
Fuel387 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Facts about engine oil consumption389 . . . . . . . . . . . . .
Used engine oil391 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Checking the engine oil level392 . . . . . . . . . . . . . . . . . . .
Checking the engine coolant level397 . . . . . . . . . . . . . . .
Spark plugs401 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

62L005±1
Temperature range anticipated before next oil change
ENGINE
380Oil capacity
Drain and refill
with filter
without filter
Oil grade
Recommended oil viscosity (SAE):
5.2 L (5.5 qt., 4.6 lmp.qt.)
4.9 L (5.2 qt., 4.3 lmp.qt.)
API SJ, ºEnergy±Conservingº multigrade engine oil or
ILSAC multigrade engine oil
± COOLING SYSTEM
Capacity
Coolant type
9.3 L (9.8 qt., 8.2 lmp.qt.)
ºToyota Long Life Coolantº or equivalent
With ethylene±glycol type coolant for a proper
corrosion protection of aluminum components
Do not use alcohol type antifreeze or plain water
alone.
± FUEL
Fuel type
Octane rating
Only UNLEADED
91 (Research octane number 96) or higher

62L005±1
Temperature range anticipated before next oil change
ENGINE
384Oil capacity
Drain and refill
with filter
without filter
Oil grade
Recommended oil viscosity (SAE):
5.4 L (5.7 qt., 4.8 lmp.qt.)
5.1 L (5.4 qt., 4.5 lmp.qt.)
API SJ, ºEnergy±Conservingº multigrade engine oil or
ILSAC multigrade engine oil
± COOLING SYSTEM
Capacity
Coolant type
7.7 L (8.1 qt., 6.8 lmp.qt.)
ºToyota Long Life Coolantº or equivalent
With ethylene±glycol type coolant for a proper
corrosion protection of aluminum components
Do not use alcohol type antifreeze or plain water
alone.
± FUEL
Fuel type
Octane rating
Only UNLEADED
91 (Research octane number 96) or higher

ENGINE
389
Gasolines quality
In a very few cases, you may experience driveability
problems caused by the particular gasoline that you are
using. If you continue to have unacceptable driveability,
try changing gasoline brands. If that does not rectify
your problem, then consult your Lexus dealer.
NOTICE
Do not use gasohol other than stated above. It
will cause fuel system damage or vehicle
performance problems.
If drivability problems are encountered (poor
hot starting, vaporizing, engine knock, etc.),
discontinue its use.
Take care not to spill gasohol during refueling.
Gasohol may cause paint damage.
Fuel tank capacity
75 L (19.8 gal., 16.5 lmp.gal.)
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.

ENGINE
390The 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 392.

ENGINE
391
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
392
CHECKING THE ENGINE OIL
LEVEL
62G005a

GS400
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.

ENGINE
393
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 full level mark ( 5
) and the low level
mark ( 4
), it is O.K.