2001 TOYOTA TUNDRA cooling

'01 TUNDRA_U (L/O 0008)
872001 TUNDRA (OM 34416U)
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 stop±and±go traffic.

Towing a trailer.
NOTICE
Do not remove the thermostat in
the engine cooling system as thismay cause the engine to overheat.The thermostat is designed to con-
trol the flow of coolant to keep thetemperature of the engine withinthe specified operating range.
Do not continue driving with anoverheated engine. See ªIf your ve-hicle overheatsº in Section 4.
Oil pressure gauge
Idling Normal
driving
The oil pressure gauge indicates engine
oil pressure when the ignition switch is
on. Check it while driving to make sure
that the needle is in the proper range.
If the oil pressure should stay below the
normal range, pull off the road to a safe
place and stop the engine immediately.
Call a Toyota dealer or qualified repair
shop for assistance.
Oil pressure may not build up when the
oil level is too low. The oil pressure
gauge is not designed to indicate oil level,
and the oil level must be checked using
the level dipstick.
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'01 TUNDRA_U (L/O 0008)
1492001 TUNDRA (OM 34416U)
Fan speed selector
Turn the knob to adjust the fan speedÐto
the right to increase, to the left to de-
crease.
Temperature selector
Turn the knob to adjust the temperatureÐ
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. PanelÐ Air flows mainly from the
instrument panel vents.
2. Bi±levelÐ Air flows from both the floor
vents and the instrument panel vents.
3. FloorÐ Air flows mainly from the floor
vents.
It is recommended to close the lower
vent. For details about it, see ªInstru-
ment panel ventsº in this section. 4. Floor/WindshieldÐ
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.
It is recommended to close the lower
vent. For details about it, see ªInstru-
ment panel ventsº in this section.
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 ªA/Cº buttonÐ
Press the ªA/Cº button for dehumidified
heating or cooling. This setting clears
the front view more quickly.
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'01 TUNDRA_U (L/O 0008)
1502001 TUNDRA (OM 34416U)
5. WindshieldÐ 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 ªA/Cº buttonÐ
Press the ªA/Cº button for dehumidified
heating or cooling. This setting clears
the front view more quickly.
It is recommended to close the lower
vent. For details about it, see ªInstru-
ment panel ventsº in this section.
For details about air flow selector settings,
see ªAir flow selector settingsº described
below. Air intake selector
The air intake selector button is used to
switch the air intake
FRESH mode that
draws outside air into the system and RE-
CIRCULATED mode that recirculates the
air inside vehicle.
To turn the air source to RECIRCULATED
mode, press the button. The indicator will
come on. To turn the air source to FRESH
mode, press the button again. The indica-
tor will go off.
To prevent fogging up of the windshield,
the air intake mode may change automati-
cally to FRESH depending on the condi-
tion of the air conditioning system.
ªA/Cº button
To turn on the air conditioning, press the
ªA/Cº button. The ªA/Cº button indicator
will come on. To turn the air conditioning
off, press the button again.
If the ªA/Cº button indicator flashes, there
is a problem in the air conditioning system
and the air conditioning automatically
shuts off. If this happens, take your ve-
hicle to a Toyota dealer for service.
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'01 TUNDRA_U (L/O 0008)
1522001 TUNDRA (OM 34416U)

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 speedÐ Any setting except ªOFFº
TemperatureÐ To w a r d s WARM
(red zone)
Air intakeÐFRESH (outside air)
Air flowÐFLOOR
Lower ventÐCLOSED
Air conditioningÐOFF

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 ªA/Cº 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 speedÐ Any setting except ªOFFº
TemperatureÐ To w a r d s COLD
(blue zone)
Air intakeÐFRESH (outside air)
Air flowÐPANEL
Air conditioningÐON

For quick cooling, move the air intake
selector to recirculate for a few min-
utes.
Ventilation
For best results, set controls to:
Fan speedÐ Any setting except ªOFFº
TemperatureÐ To w a r d s COLD
(blue zone)
Air intakeÐFRESH (outside air)
Air flowÐPANEL
Air conditioningÐOFF
Defogging
The inside of the windshield
For best results, set controls to:
Fan speedÐ Any setting except ªOFFº
TemperatureÐ To w a r d s WARM (red
zone) to heat; COLD
(blue zone) to cool
Air intakeÐFRESH (outside air)
Air flowÐWINDSHIELD
Lower ventÐCLOSED
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 RE-
CIRCULATE mode, press the air intake
selector button once again.
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'01 TUNDRA_U (L/O 0008)
1532001 TUNDRA (OM 34416U)
Vehicles with ªA/Cº buttonÐ
Press the ªA/Cº button for dehumidified
heating or cooling. This setting clears the
front view more quickly.

On humid days, do not blow cold air
on the windshieldÐthe 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 speedÐ Any setting except ªOFFº
TemperatureÐ To w a r d s WARM
(red zone)
Air intakeÐFRESH (outside air)
Air flowÐWINDSHIELD
Lower ventÐCLOSED
Turning the air flow selector to the wind-
shield or floor/windshield position turns on
the defrosting 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 RE-
CIRCULATE mode, press the air intake
selector button once again. Vehicles with ªA/Cº buttonÐ
Press the ªA/Cº 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.
Instrument panel vents
Side vents
Lower vent
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'01 TUNDRA_U (L/O 0008)
1752001 TUNDRA (OM 34416U)
NOTICE
A large amount of unburned gases
flowing into the three±way catalyticconverter may cause it to overheatand create a fire hazard. To prevent
this and other damage, observe thefollowing precautions:
Use only unleaded gasoline.
Do not drive with an extremely lowfuel 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 atidle speed for more than 20 minu-
tes.
Avoid racing the engine.
Do not push±start or pull±start yourvehicle.
Do not turn off the ignition while
the vehicle is moving.
Keep your engine in good runningorder. Malfunctions in the engineelectrical system, electronic ignitionsystem/distributor ignition system
or fuel systems could cause an ex-tremely high three±way catalyticconverter temperature.
If the engine becomes difficult tostart or stalls frequently, take yourvehicle in for a check±up as soon
as possible. Remember, your Toyotadealer knows your vehicle and itsthree±way catalytic converter sys-
tem best.
To ensure that the three±way cata-lytic converter and the entire emis-sion control system operate proper-ly, your vehicle must receive the
periodic inspections required by theToyota Maintenance Schedule. Forscheduled maintenance information,
refer to the ªScheduled MaintenanceGuideº or ªOwner 's Manual Supple-mentº.
Engine exhaust cautions
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.
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'01 TUNDRA_U (L/O 0008)
1762001 TUNDRA (OM 34416U)

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 slide±in 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 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 expressway, making it
appear that oil is excessively consumed
after driving at high speeds.
Facts about engine oil
consumption
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'01 TUNDRA_U (L/O 0008)
2472001 TUNDRA (OM 34416U)
API service symbol
ILSAC certification mark
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 SJ. The center
portion of the label shows the SAE viscos-
ity grade such as SAE 5W±30. ªEnergy±
Conservingº shown in the lower portion,
indicates that the oil has fuel±saving ca-
pabilities.
The ILSAC (International Lubricant Stan-
dardization and Approval Committee) Certi-
fication Mark is displayed on the front of
the container. Look at the see±through coolant reser-
voir when the engine is cold. The cool-
ant level is satisfactory if it is between
the ªFº and ªLº 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 ªLº line, add
coolant. Bring the level up to the ªFº line.
Always use ethylene±glycol 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.
CAUTION
To prevent burning yourself, do not
remove the radiator cap when the en-
gine is hot.
Checking the engine coolant
level
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