2003 TOYOTA 4RUNNER engine oil

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For detailed information on oil level check,
see “Checking the engine oil level” on
page 324 in Section 72.
Your engine is fitted with iridiumtipped
spark plugs.
NOTICE
Use only iridiumtipped spark plugs
and do not adjust gaps for your en-
gine performance and smooth drive-
ability.
This brake system has 2 independent hy-
draulic circuits. If either circuit should fail,
the other will still work. However, the ped-
al will be harder to press, and your stop-
ping distance will increase. Also, the
brake system warning light may come on.
CAUTION
Do not drive your vehicle with only a
single brake system. Have your
brakes fixed immediately.
BRAKE BOOSTER
The brake booster uses brake fluid pres-
surized by the pump to powerassist the
brakes. If the brake booster fails during
driving, the brake system warning light
comes on and buzzer sounds continuous-
ly. In this case, the brakes may not work
properly. If they do not work well, depress
the brake pedal firmly. If the brake system
warning light comes on, immediately stop
your vehicle and contact your Toyota deal-
er.
It is not a malfunction that the brake sys-
tem warning light may stay on for 60 sec-
onds after the ignition key is turned to the
“ON” position.
Iridiumtipped spark plugs
(2UZFE engine) Brake system

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NOTICE
If driving through water, such as
when crossing shallow streams,
first check the depth of the water
and the bottom of the river bed for
firmness. Drive slowly and avoid
deep water.
 Take all necessary safety measures
to ensure that water damage to the
engine or other components does
not occur.
Water entering the engine air intake
will cause severe engine damage.
Water can wash the grease from
wheel bearings, causing rusting and
premature failure, and may also en-
ter the differentials, transmission
and transfer case, reducing the gear
oil’s lubricating qualities.
 Sand and mud that has accumulated
in brake drums and around brake
discs may affect braking efficiency
and may damage brake system com-
ponents.
Always perform a maintenance in-
spection after each day of offroad
driving that has taken you through
rough terrain, sand, mud, or water.
For scheduled maintenance informa-
tion, refer to the “Scheduled Main-
tenance Guide” or “Owner’s Manual
Supplement”.Make sure your coolant is properly pro-
tected against freezing.
Your coolant must contain ethyleneglycol
type coolant for a proper corrosion protec-
tion of aluminum components. Use “Toyota
Genuine Long Life Coolant” or equivalent.
See page 326 in Section 72 for details
about coolant type selection.
NOTICE
Do not use alcohol type antifreeze or
plain water alone.
When it is extremely cold, we recommend
to use 60% solution for your Toyota, to
provide protection down to about 50 C
(58 F). Do not use more than 70% solu-
tion for better coolant performance.
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 start-
ing. Section 73 tells you how to visually
inspect the battery. Your Toyota dealer
and most service stations will be pleased
to check the level of charge.
Winter driving tips

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Make sure the engine oil viscosity is
suitable for the cold weather.
See page 324 in Section 72 for recom-
mended viscosity. Leaving a heavy sum-
mer oil in your vehicle during winter
months may cause harder starting. If you
are not sure about which oil to use, call
your Toyota dealer—he will be pleased to
help.
Keep the door locks from freezing.
Squirt lock deicer or glycerine into the
locks to keep them from freezing.
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 dam-
age your vehicle’s paint.
Do not use your parking brake when
there is a possibility it could freeze.
When parking, put the transmission into
“P” and block the front wheels. Do not
use the parking brake, or snow or water
accumulated in and around the parking
brake 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
vehicle are tire chains, window scraper,
bag of sand or salt, flares, small shovel,
jumper cables, etc.
Your vehicle is not designed to be
dinghy towed (with four wheels on the
ground) behind a motorhome.
NOTICE
Do not tow your vehicle with four
wheels on the ground. This may
cause serious damage to your vehicle.
Dinghy towing

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Accelerate slowly and smoothly.
Avoid jackrabbit starts. Get into high
gear as quickly as possible.
Avoid long engine idling. If you have
a long wait and you are not in traffic,
it is better to turn off the engine and
start again later.
Avoid engine lugging or overrev-
ving. Use a gear position suitable for
the road on which you are travelling.
Avoid continuous speeding up and
slowing down. Stopandgo driving
wastes fuel.
Avoid unnecessary stopping and
braking. Maintain a steady pace. Try
to time the traffic signals so you only
need to stop as little as possible or
take advantage of through streets to
avoid traffic lights. Keep a proper dis-
tance from other vehicles to avoid sud-
den braking. This will also reduce wear
on your brakes.
Avoid heavy traffic or traffic jams
whenever possible.
Do not rest your foot on the brake
pedal. This causes premature wear,
overheating and poor fuel economy.
Maintain a moderate speed on high-
ways. The faster you drive, the greater
the fuel consumption. By reducing your
speed, you will cut down on fuel con-
sumption.
Keep the front wheels in proper
alignment. Avoid hitting the curb and
slow down on rough roads. Improper
alignment not only causes faster tire
wear but also puts an extra load on
the engine, which, in turn, wastes fuel.
Keep the bottom of your vehicle free
from mud, etc. This not only lessens
weight but also helps prevent corro-
sion.
Keep your vehicle tunedup and in
top shape. A dirty air cleaner, improp-
er valve clearance, dirty plugs, dirty oil
and grease, brakes not adjusted, etc.
all lower engine performance and con-
tribute to poor fuel economy. For longer
life of all parts and lower operating
costs, keep all maintenance work on
schedule, and if you often drive under
severe conditions, see that your vehicle
receives more frequent maintenance.
(For scheduled maintenance informa-
tion, please refer to the “Scheduled
Maintenance Guide” or “Owner ’s Manu-
al Supplement”.)
CAUTION
Never turn off the engine to coast
down hills. Your power steering and
brake booster will not function with-
out the engine running. Also, the
emission control system operates
properly only when the engine is run-
ning.

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If your engine coolant temperature
gauge indicates overheating, if you ex-
perience a loss of power, or if you hear
a loud knocking or pinging noise, the
engine has probably overheated. You
should follow this procedure...
1. Pull safely off the road, stop the ve- hicle and turn on your emergency
flashers. Put the transmission in “P”
and apply the parking brake. Turn off
the air conditioning if it is being used.
2. If coolant or steam is boiling out of the radiator or reservoir, stop the engine.
Wait until the steam subsides before
opening the hood. If there is no coolant
boiling over or steam, leave the engine
running.
CAUTION
To help avoid personal injury, keep
the hood closed until there is no
steam. Escaping steam or coolant is
a sign of very high pressure.
3. Look for obvious coolant leaks from theradiator, hoses, and under the vehicle.
However, note that water draining from
the air conditioning is normal if it has
been used.
CAUTION
When the engine is running, keep
hands and clothing away from the
moving fan and engine drive belts.
4. If the engine drive belt is broken or thecoolant is leaking, stop the engine im-
mediately. Call a Toyota dealer for as-
sistance.
5. If the engine drive belt is O.K. and there are no obvious leaks, you may
help the engine cool down more quickly
by running it at about 1500 rpm for a
few minutes with the accelerator pedal
lightly depressed.
6. Check the coolant reservoir. If it is dry, add coolant to the reservoir while the
engine is running. Fill it about half full.
CAUTION
Do not attempt to remove the radiator
cap when the engine and radiator are
hot. Serious injury could result from
scalding hot fluid and steam blown
out under pressure.
7. After the engine coolant temperaturehas cooled to normal, again check the
coolant level in the reservoir. If neces-
sary, bring it up to half full again. Seri-
ous coolant loss indicates a leak in the
system. You s hould have it checked as
soon as possible at your Toyota dealer.
If your vehicle overheats

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If you are a skilled doityourself mechan-
ic, the Toyota service manuals are recom-
mended. Please be aware that doityour-
self maintenance can affect your warranty
coverage. See “Owner ’s Warranty Informa-
tion Booklet” or “Owner ’s Manual Supple-
ment” for the details. Listed below are the general maintenance
items that should be performed as fre-
quently as specified. In addition to check-
ing the items listed, if you notice any
unusual noise, smell or vibration, you
should investigate the cause or take your
vehicle to your Toyota dealer or a quali-
fied service shop immediately. It is recom-
mended that any problem you notice be
brought to the attention of your dealer or
the qualified service shop for their advice.
CAUTION
Make these checks only with ade-
quate ventilation if you run the en-
gine.
OUTSIDE THE VEHICLE
Items listed below should be performed
from time to time, unless otherwise
specified.
Tire pressure
Check the pressure with a gauge every
two weeks, or at least once a month. See
page 332 in Section 72 for additional
information.Tire surface and wheel nuts
Check the tires carefully for cuts, damage
or excessive wear. See page 333 in Sec-
tion 72 for additional information. When
checking the tires, make sure no nuts are
missing, and check the nuts for loose-
ness. Tighten them if necessary.
Tire rotation
Rotate the tires according to the mainte-
nance schedule. (For scheduled mainte-
nance information, please refer to the sep-
arate “Scheduled Maintenance Guide” or
“Owner ’s Manual Supplement”.) See page
334 in Section 72 for additional informa-
tion.
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 back door
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.
General maintenance

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Battery condition
Check the battery condition by the indica-
tor color. See page 340 in Section 73 for
additional information.
Brake fluid level
Make sure the brake fluid level is correct.
See page 328 in Section 72 for addition-
al information.
Engine oil level
Check the level on the dipstick with the
engine turned off and the vehicle parked
on a level spot. See page 324 in Section
72 for additional 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 page 329 in Section 72 for addition-
al 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” on
page 247 in Section 2.) Be on the alert for changes in perfor-
mance, sounds, and visual tipoffs 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.)
Flatlooking 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 normalIf you notice any of these clues, take your
vehicle to your Toyota dealer as soon as
possible. It probably needs adjustment or
repair.
CAUTION
Do not continue driving with the ve-
hicle unchecked. It could result in se-
rious vehicle damage and possibly
personal injury.
Does your vehicle need
repairing?

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1. Windshield and back window washer
fluid tank
2. Power steering fluid reservoir
3. Engine oil level dipstick
4. Engine coolant reservoir
5. Engine oil filler cap
6. Brake fluid reservoir
7. Fuse block
8. Battery
9. Condenser
10. Radiator
Engine compartment overview
 1GRFE engine