2003 TOYOTA TACOMA cooling

’03 Tacoma U (L/O 0209)
11 72003 MY TACOMA (OM35800U)
The gauge indicates the engine coolant
temperature when the ignition switch is
on. The engine operating temperature
will vary with changes in weather and
engine load.
If the needle moves into the red zone,
your engine is too hot. If your vehicle
overheats, stop your vehicle and allow the
engine to cool.
Your vehicle may overheat during severe
operating conditions, such as:
Driving up a long hill on a hot day.
Reducing speed or stopping after high
speed driving.
Idling for a long period with the air
conditioning on in stopandgo traffic.
Towing a trailer.
NOTICE
Do not remove the thermostat in
the engine cooling system as this
may cause the engine to overheat.
The thermostat is designed to con-
trol the flow of coolant to keep the
temperature of the engine within
the specified operating range.
 Do not continue driving with an
overheated engine. See “If your ve-
hicle overheats” in Section 4.
The tachometer indicates engine speed
in thousands of rpm (revolutions per
minute). Use it while driving to select
correct shift points and to prevent en-
gine lugging and overrevving.
Driving with the engine running too fast
causes excessive engine wear and poor
fuel economy. Remember, in most cases
the slower the engine speed, the greater
the fuel economy.
NOTICE
Do not let the indicator needle get
into the red zone. This may cause
severe engine damage.
Tachometer

’03 Tacoma U (L/O 0209)
1732003 MY TACOMA (OM35800U)
Fan speed selector
Turn the knob to adjust the fan speed—to
the right to increase, to the left to de-
crease.
Temperature selector
Turn the knob to adjust the temperature—
to the right to warm, to the left to cool.
Air flow selector
Turn the knob to select the vents used for
air flow.1. Panel— Air flows mainly from the
instrument panel vents.
2. Bilevel— Air flows from both the floor
vents and the instrument panel vents.
3. Floor— Air flows mainly from the floor
vents.
4. Floor/Windshield— Air flows mainly
from the floor vents and windshield
vents.
Turning the air flow selector to the
floor/windshield position turns on the
defogging function with the purpose of
clearing the front view. This position allows the air intake to
select FRESH automatically. This is to
clean up the front view more quickly.
If you want to return the setting to
RECIRCULATE mode, press the air in-
take selector button once again.
Vehicles with “A/C” button—
Press the “A/C” button for dehumidified
heating or cooling. This setting clears
the front view more quickly.
5. Windshield— Air flows mainly from the
windshield vents.
Turning the air flow selector to the
windshield position turns on the defog-
ging function with the purpose of clear-
ing the front view.
This position allows the air intake to
select FRESH automatically. This is to
clean up the front view more quickly.
If you want to return the setting to
RECIRCULATE mode, press the air in-
take selector button once again.
Vehicles with “A/C” button—
Press the “A/C” button for dehumidified
heating or cooling. This setting clears
the front view more quickly.

’03 Tacoma U (L/O 0209)
1762003 MY TACOMA (OM35800U)
If following another vehicle on a dusty
road, or driving in windy and dusty
conditions, it is recommended that the
air intake selector be temporarily set to
RECIRCULATE, which will close off the
outside passage and prevent outside
air and dust from entering the vehicle
interior.Heating
For best results, set controls to:
Fan speed— Any setting except “OFF”
Temperature— To w a r d s WARM
(red zone)
Air intake—FRESH (outside air)
Air flow—FLOOR
Air conditioning—OFF
For quick heating, select recirculated
air for a few minutes. To keep the
windows from fogging, select fresh af-
ter the vehicle interior has been
warmed.
Press the “A/C” button on for dehumidi-
fied heating.
Choose floor/windshield air flow to heat
the vehicle interior while defrosting or
defogging the windshield. Air conditioning
For best results, set controls to:
Fan speed— Any setting except “OFF”
Temperature— To w a r d s COLD
(blue zone)
Air intake—FRESH (outside air)
Air flow—PANEL
Air conditioning—ON
For quick cooling, move the air intake
selector to recirculate for a few min-
utes.
Ventilation
For best results, set controls to:
Fan speed— Any setting except “OFF”
Temperature— To w a r d s COLD
(blue zone)
Air intake—FRESH (outside air)
Air flow—PANEL
Air conditioning—OFF

’03 Tacoma U (L/O 0209)
1772003 MY TACOMA (OM35800U)
Defogging
The inside of the windshield
For best results, set controls to:Fan speed— Any setting except “OFF”
Temperature— To w a r d s WARM
(red zone) to heat;
COLD (blue zone) to
cool
Air intake—FRESH (outside air)
Air flow—WINDSHIELD
Turning the air flow selector to the wind-
shield or floor/windshield position turns on
the defogging function with the purpose of
clearing the front view.
When turning the air flow selector to wind-
shield or floor/windshield position, the air
intake selects FRESH automatically. This
is to clean up the front view more quickly.
If you want to return the setting to
RECIRCULATE mode, press the air intake
selector button once again.
Vehicles with “A/C” button—
Press the “A/C” button for dehumidified
heating or cooling. This setting clears the
front view more quickly.
On humid days, do not blow cold air
on the windshield—the difference be-
tween the outside and inside tempera-
tures could make the fogging worse.
Defrosting
The outside of the windshield
For best results, set controls to:
Fan speed— Any setting except “OFF”
Temperature— To w a r d s WARM
(red zone)
Air intake—FRESH (outside air)
Air flow—WINDSHIELD
Turning the air flow selector to the wind-
shield or floor/windshield position turns on
the defogging function with the purpose of
clearing the front view.
When turning the air flow selector to wind-
shield or floor/windshield position, the air
intake selects FRESH automatically. This
is to clean up the front view more quickly.
If you want to return the setting to
RECIRCULATE mode, press the air intake
selector button once again.
Vehicles with “A/C” button—
Press the “A/C” button for dehumidified
heating or cooling. This setting clears the
front view more quickly.
To heat the vehicle interior while de-
frosting the windshield, choose floor/
windshield air flow.

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1962003 MY TACOMA (OM35800U)
NOTICE
A large amount of unburned gases
flowing into the threeway catalytic
converter may cause it to overheat
and create a fire hazard. To prevent
this and other damage, observe the
following precautions:
Use only unleaded gasoline.
 Do not drive with an extremely low
fuel level; running out of fuel could
cause the engine to misfire, creat-
ing an excessive load on the three
way catalytic converter.
 Do not allow the engine to run at
idle speed for more than 20 minu-
tes.
 Avoid racing the engine.
 Do not pushstart or pullstart your
vehicle.
 Do not turn off the ignition while
the vehicle is moving.
Keep your engine in good running
order. Malfunctions in the engine
electrical system, electronic ignition
system/distributor ignition system
or fuel systems could cause an ex-
tremely high threeway catalytic
converter temperature.
 If the engine becomes difficult to
start or stalls frequently, take your
vehicle in for a checkup as soon
as possible. Remember, your Toyota
dealer knows your vehicle and its
threeway catalytic converter sys-
tem best.
 To ensure that the threeway cata-
lytic converter and the entire emis-
sion control system operate proper-
ly, your vehicle must receive the
periodic inspections required by the
Toyota Maintenance Schedule. For
scheduled maintenance information,
refer to the “Scheduled Maintenance
Guide” or “Owner ’s Manual Supple-
ment”.CAUTION
Avoid inhaling the engine exhaust.
It contains carbon monoxide, which
is a colorless and odorless gas. It
can cause unconsciousness or even
death.
Make sure the exhaust system has
no holes or loose connections. The
system should be checked from
time to time. If you hit something,
or notice a change in the sound of
the exhaust, have the system
checked immediately.
Do not run the engine in a garage
or enclosed area except for the
time needed to drive the vehicle in
or out. The exhaust gases cannot
escape, making this a particularly
dangerous situation.
Do not remain for a long time in a
parked vehicle with the engine run-
ning. If it is unavoidable, however,
do so only in an unconfined area
and adjust the heating or cooling
system to force outside air into the
vehicle.
Engine exhaust cautions

’03 Tacoma U (L/O 0209)
1972003 MY TACOMA (OM35800U)
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. Have the cause immediately
located and corrected.
Toyota does not recommend occu-
pying the rear cargo area when it
is fitted with a slidein camper,
camper shell or other type cover
while the engine is running. This
caution applies to both driving and
stopped or parked situations with
the engine running. Particular care
should be taken to prevent exhaust
gases from entering camper bodies,
trailers or other enclosures on or
around your vehicle. If exhaust
fumes are detected, open all win-
dows and thoroughly ventilate the
area.
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 highspeed 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 expressway, making it
appear that oil is excessively consumed
after driving at high speeds.
Facts about engine oil
consumption

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2142003 MY TACOMA (OM35800U)
CAUTION
The maximum gross trailer weight
(trailer weight plus cargo weight)
must never exceed the following.Twowheel drive models except
Pre Runner2RZFE and 5VZFE engines 1587 kg (3500 lb.)
Fourwheel drive models and Pre
Runner 3RZFE engine
1587 kg (3500 lb.)
5VZFE engine Without towing package
∗
1587 kg (3500 lb.)
With towing package∗
2721 kg (6000 lb.)
If towing a trailer and cargo weigh-
ing over 907 kg (2000 lb.), it is
necessary to use a sway control
device with sufficient capacity. The
combination of the gross trailer
weight added to the total weight of
the vehicle, occupants and vehicle
cargo must never exceed a total of
the following.
Twowheel drive models except Pre
Runner 2RZFE engine 3035 kg (6700 lb.)
5VZFE engine 3080 kg (6800 lb.)
Fourwheel drive models and Pre
Runner 3RZFE engine 3355 kg (7400 lb.)
5VZFE engine Without towing package
∗
3401 kg (7500 lb.)
With towing package∗
4535 kg (10000 lb.)
Exceeding the maximum weight of
the trailer, the vehicle, or the ve-
hicle and trailer combination, can
cause an accident resulting in seri-
ous personal injuries.
∗: To distinguish towing package, refer to
the following illustration.
GreenWith towing package
OrangeWithout towing package
How to distinguish towing package
Engine compartment
Cooling fan
Front of vehicle

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2682003 MY TACOMA (OM35800U)
Oil identification marks
Either or both API registered marks are
added to some oil containers to help
you select the oil you should use.
The API Service Symbol is located any-
where on the outside of the container.
The top portion of the label shows the oil
quality by API (American Petroleum Insti-
tute) designations such as SL. The center
portion of the label shows the SAE viscos-
ity grade such as SAE 5W30. “Energy
Conserving” shown in the lower portion,
indicates that the oil has fuelsaving ca-
pabilities.
The ILSAC (International Lubricant Stan-
dardization and Approval Committee) Certi-
fication Mark is displayed on the front of
the container.
To ensure excellent lubrication perfor-
mance for your engine, the “Toyota
Genuine Motor Oil” range is available,
which has been specifically tested and
approved for all Toyota engines.
Please contact your Toyota dealer for fur-
ther details of the “Toyota Genuine Motor
Oil” range.Look at the seethrough coolant reser-
voir when the engine is cold. The cool-
ant level is satisfactory if it is between
the “F” and “L” lines on the reservoir.
If the level is low, add ethyleneglycol
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 “L” line, add
coolant. Bring the level up to the “F” line.
Always use ethyleneglycol type coolant
for a proper corrosion protection of alumi-
num 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. Visually check the
radiator, hoses, radiator cap and drain
cock and water pump.
If you can find no leak, have your Toyota
dealer test the cap pressure and check
for leaks in the cooling system.
Checking the engine coolant
level