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FUNCTIONS OF ENGINE OIL 
Engine oil has the primary functions of lu- 
bricating and cooling the inside of the en-
gine, 
and plays a major role in maintaining
the engine in proper working order. ENGINE OIL CONSUMPTION 
It is normal that an engine should con- 
sume 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 isleft 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 com-
bustion gases during the combustionprocess.  
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 tem-perature 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 conditions
the vehicle is driven under. More oil is consumed by high-speed  driv-
ing and frequent acceleration and decel- eration. 
A new engine consumes more oil, since 
its pistons, piston rings and cylinder walls
have not become conditioned. 
When  judging the amount of oil con- 
sumption,  note that the oil may be-come diluted and make it difficult to
judge the true level accurately. 
As an example, if a vehicle is used for re- 
peated short trips, and consumes a nor- mal 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 the 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 itappear 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 essen-
tial that the oil level be checked regularly.
Toyota recommends that the oil level bechecked  every time you refuel the vehicle.
NOTICE
Failure to check the oil level regular- ly could lead to serious engine
trouble due to insufficient oil.
For detailed information on the oil level 
check,  see Checking the engine oil levelº
in Chapter 7-2.
Facts about engine oil consumption 

143
Make sure you have ethylene-glycol 
antifreeze in the radiator.
NOTICE
Do not use alcohol type antifreeze.
Check the condition of the battery and cables. Cold temperatures reduce the capacity of 
any battery, so it must be in top shape to provide enough power for winter starting.Chapter 7-3 tells you how to visually in- 
spect the battery. Your Toyota dealer and 
most service stations will be pleased tocheck the level of charge. 
Make sure the engine oil viscosity is 
suitable for the cold weather. 
See Chapter 7-2 for recommended vis- 
cosity.  Leaving a heavy summer oil in your
vehicle during winter months may cause
harder starting. If you are not sure about
which oil to use, call your Toyota deal- erÐhe will be pleased to help. Keep the door locks from freezing. Squirt lock de-icer or glycerine into the 
locks to  keep them from freezing. To open
a frozen lock, try heating the key before in-serting it. Use a washer fluid containing an anti- 
freeze solution. 
This product is available at your Toyota 
dealer and most auto parts stores. Follow
the manufacturer's directions for how 
much to mix with water.
NOTICE
Do not use engine antifreeze or any other substitute because it may
damage your vehicle's paint.
Do not use your parking brake when there is a possibility it could freeze. When parking, put the transmission into 
Pº (automatic) or into first or reverse
(manual) and block the rear wheels. Do 
not use the parking brake, or snow or wa- 
ter accumulated in and around the parkingbrake mechanism may freeze, making it 
hard to release. Keep  ice and snow from accumulating
under the fenders. 
Ice and snow built up under your fenders 
can make steering difficult. During bad winter driving, stop and check under the
fenders occasionally. Depending  on where you are driving, 
we recommend you carry some emer- gency equipment. 
Some of 
the things you might put in the ve-
hicle are tire chains, window scraper, bag of sand or salt, flares, small shovel, jump- er cables, etc.
Winter driving tips