1998 TOYOTA SIENNA oil change

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Keep the back door and quarter
windows closed while driving. An
open or unsealed back door and
quarter windows may cause exhaust
gases to be drawn into the vehicle.
To allow proper operation of your
vehicle’s ventilation system, keep
the inlet grilles in front of the wind-
shield clear of snow, leaves, or oth-
er obstructions.
If you smell exhaust fumes in the
vehicle, drive with the windows
open and the back door and quarter
windows closed. Have the cause im-
mediately located and corrected.
FUNCTIONS OF ENGINE OIL
Engine oil has the primary functions of
lubricating and cooling the inside of the
engine, and plays a major role in main-
taining 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
is left on the cylinder wall when a pis-
ton 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 tem-
perature exhaust gases also burn the
oil used to lubricate the exhaust valve
stems.The amount of engine oil consumed de-
pends 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 become
diluted and make it difficult to judge
the true level accurately.
As an example, if a vehicle is used for
repeated 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 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 express way, making it
appear that oil is excessively consumed
after driving at high speeds.
Facts about engine oil
consumption
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Tire surface and wheel nuts
Check the tires carefully for cuts, damage
or excessive wear. See Chapter 7−2 for
additional information. When checking the
tires, make sure no nuts are missing, and
check the nuts for looseness. Tighten
them if necessary.
Tire rotation
Rotate the tires every 12000 km (7500
miles). See Chapter 7−2 for additional in-
formation.
Fluid leaks
Check underneath for leaking fuel, oil, wa-
ter or other fluid after the vehicle has
been parked for a while. If you smell fuel
fumes or notice any leak, have the cause
found and corrected immediately.
Doors and engine hood
Check that all doors including trunk lid
operate smoothly and all latches lock se-
curely. Make sure the engine hood sec-
ondary latch secures the hood from open-
ing when the primary latch is released.
INSIDE THE VEHICLE
Items listed below should be checked
regularly, e.g. while performing periodic
services, cleaning the vehicle, etc.Lights
Make sure the headlights, stop lights, tail
lights, turn signal lights, and other lights
are all working. Check headlight aim.
Service reminder indicators and warning
buzzers
Check that all service reminder indicators
and warning buzzers function properly.
Steering wheel
Be alert for changes in steering condition,
such as hard steering or strange noise.
Seats
Check that all seat controls such as seat
adjusters, seatback recliner, etc. operate
smoothly and that all latches lock securely
in any position. Check that the head re-
straints move up and down smoothly and
that the locks hold securely in any latched
position. For folding−down rear seatbacks
and detachable rear seats, check that the
latches lock securely.
Seat belts
Check that the seat belt system such as
buckles, retractors and anchors operate
properly and smoothly. Make sure the belt
webbing is not cut, frayed, worn or dam-
aged.Accelerator pedal
Check the pedal for smooth operation and
uneven pedal effort or catching.
Brake pedal
Check the pedal for smooth operation and
that the pedal has the proper clearance.
Check the brake booster function.
Brakes
At a safe place, check that the brakes do
not pull to one side when applied.
Parking brake
Check that the pedal has the proper travel
and that, on a safe incline, your vehicle
is held securely with only the parking
brake applied.
Automatic transmission ”Park” mecha-
nism
On a safe incline, check that your vehicle
is held securely with the selector lever in
”P” position and all brakes released.
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IN THE ENGINE COMPARTMENT
Items listed below should be checked
from time to time, e.g. each time when
refueling.
Washer fluid
Make sure there is sufficient fluid in the
tank. See Chapter 7−3 for additional in-
formation.
Engine coolant level
Make sure the coolant level is between
the ”FULL” and ”LOW” lines on the see−
through reservoir when the engine is cold.
See Chapter 7−2 for additional information.
Battery electrolyte level
Make sure the electrolyte level of all bat-
tery cells is between upper and lower lev-
el lines on the case. Add only distilled
water when replenishing. See Chapter 7−3
for additional information.
Brake fluid level
Make sure the brake fluid level is correct.
See Chapter 7−2 for additional information.
Engine oil level
Check the level on the dipstick with the
engine turned off and the vehicle parked
on a level spot. See Chapter 7−2 for addi-
tional information.Power steering fluid level
Check the level through the reservoir. The
level should be in the ”HOT” or ”COLD”
range depending on the fluid temperature.
See Chapter 7−2 for additional information.
Exhaust system
If you notice any change in the sound of
the exhaust or smell exhaust fumes, have
the cause located and corrected immedi-
ately. (See engine exhaust cautions in
Part 2.)Be on the alert for changes in perfor-
mance, sounds, and visual tip−offs that
indicate service is needed. Some impor-
tant clues are as follows:
Engine missing, stumbling, or pinging
Appreciable loss of power
Strange engine noises
A leak under the vehicle (however, wa-
ter dripping from the air conditioning
after use is normal.)
Change in exhaust sound (This may
indicate a dangerous carbon monoxide
leak. Drive with the windows open and
have the exhaust system checked im-
mediately.)
Flat−looking tire; excessive tire squeal
when cornering; uneven tire wear
Vehicle pulls to one side when driving
straight on a level road
Strange noises related to suspension
movement
Loss of brake effectiveness; spongy
feeling brake pedal; pedal almost
touches floor; vehicle pulls to one side
when braking
Engine coolant temperature continually
higher than normal
Does your vehicle need
repairing?
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