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ENGINE
314The 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 315.
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ENGINE
315
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
SV62004
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.
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ENGINE
316
SV62002
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 low level mark ( 4 ) and
the full level mark ( 5 ), it is O.K.
NOTICE
Be careful not to drop the engine oil on the vehicle
components.
SV62008
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)
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ENGINE
317
NOTICE
Be careful not to spill the engine oil on the vehiclecomponents.
Avoid overfilling, or the engine could be damaged.Check the oil level on the dipstick once again afteradding the oil.
Engine oil selection
ºToyota Genuine Motor Oilº is filled in your Lexus vehicle. Use
Lexus approved ºToyota Genuine Motor Oilº or equivalent to
satisfy the following grade and viscosity.
Oil grade:
API grade SL ºEnergy±Conservingº or ILSAC multigrade
engine oil.
Recommended viscosity (SAE):
SOIL14
Outside temperature
SAE 5W±30 is the best choice for good fuel economy, and
good starting in cold weather.
If SAE 5W±30 oil is not available, SAE 10W±30 oil may be
used. However, it should be replaced with SAE 5W±30 at
the next oil change.
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ENGINE
319
CHECKING THE ENGINE COOLANTLEVEL
SV62006
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 ºLº 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 ºLº 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. 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.
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 ºToyota
Genuine Long Life Coolantº in your Lexus vehicle. In order to
avoid technical problems, we strongly recommend using
ºToyota 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 310.
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ENGINE
320We recommend to use 50% solution for your Lexus, to provide
protection
down to about ±35 C (±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 ºToyota 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
ºToyota 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 you vehicle to Lexus dealer.
CAUTION
To prevent yourself from burning, be careful not to
touch the radiator or co ndenser when the engine is hot.
NOTICE
To prevent damage to the radiator and condenser, do
not perform the work by yourself.
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CHASSIS
330
CHECKING POWER STEERINGFLUID
SV63002
Check the fluid level on the dipstick. If necessary, add
automatic transmission fluid DEXRONII or III.
If the vehicle has been driven around 80 km/h (50 mph) for 20
minutes (a little more in frigid temperatures), the fluid is hot
(60 C ± 80C or 140F ± 175F). You may also check the level
when the fluid is cold (about room temperature, 10 C ± 30C
or 50F ± 85F) if the engine has not been run for about five
hours.
SV63003
1If cold O.K. 2If hot O.K. 3Add fluid
1. Clean all dirt off the reservoir.
2. Remove the reservoir cap by turning it counterclockwise
and wipe the dipstick clean.
3. Reinstall the reservoir cap.
4. Remove the reservoir cap again and look at the fluid level.
If the fluid is cold, the level should be in the ºCOLDº range on
the dipstick. Similarly, if it is hot, the fluid level should be in the
ºHOTº range. If the level is at the low side of either range, add
automatic transmission fluid DEXRON
II or III to bring the
level within the range.
5. After replacing the reservoir cap, visually check the
steering box case, vane pump and hose connections for leaks
or damage.
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ELECTRICAL COMPONENTS
349
Checking battery exterior
SV64002
1Terminals 2Hold±down clamp
Check the battery for corroded or loose connections,
cracks, or loose hold±down clamps.
1. If the battery is corroded, wash it off with a solution of warm
water and baking soda. Coat the terminals with grease to
prevent further corrosion.
2. If the connections are loose, tighten the clamp bolts ± but
do not overtighten.
3. Tighten the hold±down clamp only enough to keep the
battery firmly in place. Overtightening may damage the battery
case.
NOTICE
Make sure the engine and all accessories are turned off before performing maintenance.
When checking the battery, remove the ground cable
first and reinstall it last.
Be careful not to cause a short circuit with tools.
Take care no solution gets into the battery when washing it.
2003 IS300 from Aug. '02 Prod. (OM53439U)