Page 297 of 420

04_SEQUOIA_U (L/O 0309)
289
2004 SEQUOIA from Sep. ’03 Prod. (OM34423U)
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.
Keep the back door and back win-
dow closed while driving. An open
or unsealed back door and back
window, 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 back
window 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.
Engine exhaust cautionsFacts about engine oil
consumption
Page 298 of 420

04_SEQUOIA_U (L/O 0309)
290
2004 SEQUOIA from Sep. ’03 Prod. (OM34423U)
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.
Oil consumption: Max. 1.0 L per 1000
km (1.1 qt./600 miles, 0.9 lmp. qt./600
miles) 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.
IMPORTANCE OF ENGINE OIL LEVEL
CHECK
One of the most important points in prop-
er vehicle maintenance is to keep the en-
gine oil at the optimum level so that oil
function will not be impaired. Therefore, it
is essential that the oil level be checked
regularly. Toyota recommends that the oil
level be checked every time you refuel
the vehicle.NOTICE
Failure to check the oil level regularly
could lead to serious engine trouble
due to insufficient oil.
For detailed information on oil level check,
see “Checking the engine oil level” on
page 370 in Section 7
−2.
Page 299 of 420

04_SEQUOIA_U (L/O 0309)
291
2004 SEQUOIA from Sep. ’03 Prod. (OM34423U)
The tandem master cylinder brake system
is a hydraulic system with two separate
sub−systems. If either sub −system s hould
fail, the other will still work. However, the
pedal will be harder to press, and your
stopping 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 engine vacuum to
power −assist the brakes. If the engine
should quit while you are driving, you can
bring the vehicle to a stop with normal
pedal pressure. There is enough reserved
vacuum for one or two stops—but no
more!
CAUTION
Do not pump the brake pedal if the
engine stalls. Each push on the
pedal uses up your reserved vacu-
um.
Even if the power assist is com-
pletely lost, the brakes will still
work. But you will have to push the
pedal hard, much harder than nor-
mal. And your braking distance will
increase.
ANTI LOCK BRAKE SYSTEM
(with “ABS” warning light)
The anti lock brake system is designed
to help prevent lock up of the wheels
during a sudden braking or braking on
slippery road surfaces. This assists in
providing directional stability and steer-
ing performance of the vehicle under
these circumstances.
Effective way to press the ABS brake
pedal: When the anti −lock brake system
function is in action, you may feel the
brake pedal pulsating and hear a noise.
In this situation, to let the anti −lock
brake system work for you, just hold the
brake pedal down more firmly. Do not
pump the brake in a panic stop. This
will result in reduced braking performan-
ce.
The anti −lock brake system becomes op-
erative after the vehicle has accelerated
to a speed in excess of approximately 10
km/h (6 mph). It stops operating when the
vehicle decelerates to a speed below
approximately 5 km/h (3 mph).
Brake system
Page 300 of 420

04_SEQUOIA_U (L/O 0309)
292
2004 SEQUOIA from Sep. ’03 Prod. (OM34423U)
Depressing the brake pedal on slippery
road surfaces such as on a manhole cov-
er, a steel plate at a construction site,
joints in a bridge, etc. on a rainy day
tends to activate the anti−lock brake sys-
tem.
You may hear a click or motor sound in
the engine compartment for a few seconds
when the engine is started or just after
the vehicle begins to move. This means
that the anti −lock brake system is in the
self −check mode, and does not indicate a
malfunction.
When the anti lock brake system is ac-
tivated, the following conditions may
occur. They do not indicate a malfunc-
tion of the system:
You may hear the anti −lock brake sys-
tem operating and feel the brake pedal
pulsating and the vibrations of the ve-
hicle body and steering wheel. You
may also hear the motor sound in the
engine compartment even after the ve-
hicle is stopped.
At the end of the anti −lock brake sys-
tem activation, the brake pedal may
move a little forward.
CAUTION
Do not overestimate the anti lock
brake system: Although the anti lock
brake system assists in providing ve-
hicle control, it is still important to
drive with all due care and maintain
a moderate speed and safe distance
from the vehicle in front of you, be-
cause there are limits to the vehicle
stability and effectiveness of steering
wheel operation even with the anti
lock brake system on.
If tire grip performance exceeds its
capability, or if hydroplaning occurs
during high speed driving in the rain,
the anti lock brake system does not
provide vehicle control.
Anti lock brake system is not de-
signed to shorten the stopping dis-
tance: Always drive at a moderate
speed and maintain a safe distance
from the vehicle in front of you.
Compared with vehicles without an
anti lock brake system, your vehicle
may require a longer stopping dis-
tance in the following cases:
Driving on rough, gravel or snow
covered roads.
Driving with tire chains installed.
Driving over the steps such as the
joints on the road.
Driving on roads where the road
surface is pitted or has other differ-
ences in surface height.
Install all 4 tires of specified size at
appropriate pressure: The anti lock
brake system detects vehicle speeds
using the speed sensors for respec-
tive wheels’ turning speeds. The use
of tires other than specified may fail
to detect the accurate turning speed
resulting in a longer stopping dis-
tance.
Page 301 of 420

04_SEQUOIA_U (L/O 0309)
293
2004 SEQUOIA from Sep. ’03 Prod. (OM34423U)
Ty p e A
Ty p e B
“ABS” warning light
The light comes on when the ignition key
is turned to the “ON” position. If the anti−
lock brake system and the brake assist
system work properly, the light turns off
after a few seconds. Thereafter, if either
of the systems malfunctions, the light
comes on again.
When the “ABS” warning light is on (and
the brake system warning light is off), the
anti −lock brake system, the brake assist
system and the traction control system
and/or the vehicle stability control system
do/does not operate, but the brake system
still operates conventionally.
When the “ABS” warning light is on (and
the brake system warning light is off), the
anti −lock brake system does not operate
so that the wheels could lock up during
a sudden braking or braking on slippery
road surfaces. If either of the following conditions
occurs, this indicates a malfunction
somewhere in the components moni-
tored by the warning light system. Con-
tact your Toyota dealer as soon as
possible to service the vehicle.
The light does not come on when the
ignition key is turned to the “ON” posi-
tion, or remains on.
The light comes on while you are dri-
ving.
A warning light turning on briefly during
operation does not indicate a problem.
CAUTION
If the “ABS” warning light remains on
together with the brake system warn-
ing light, immediately stop your ve-
hicle at a safe place and contact your
Toyota dealer.
In this case, not only the anti lock
brake system will fail but also the
vehicle will become extremely unsta-
ble during braking.
Page 302 of 420