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Brake system
TANDEM MASTER CYLINDER BRAKE SYSTEM
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 be longer. 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 reserve
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 vacuum reserve.
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
be longer.
ANTI-LOCK BRAKE SYSTEM (with
”ABS” warning light)
The anti-lock brake system is designed to
automatically help prevent lock −up of the
wheels during sudden braking or braking
on slippery road surfaces. This assists in
providing directional stability and steering
performance of the vehicle under these
circumstances.
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). You may hear a sound in the engine
compartment for a few seconds when the
engine is started or just after the vehicle
is started. This means that the anti-lock
brake system is in the self check mode,
and does not indicate a malfunction.
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. This will result in
reduced braking performance.
The brake pedal pulsation caused by the
anti-lock brake system may indicate haz-
ardous road surface conditions. Although
the anti-lock brake system assists in pro-
viding vehicle control, it is still important
to drive with all due care, because the
anti-lock brake system cannot overcome
the laws of physics that act on your ve-
hicle: Braking capability is dependent on tire
friction with the road surface.
T100(U)
136
However, if towing with a fifth wheel
trailer, the cargo load must be distrib-
uted so that the tongue load is 19 to
21% of the total trailer weight. Never
load the trailer with more weight in
the back than in the front. About 60%
of the trailer load should be in the
front half of the trailer and the re-
maining 40% in the rear.
HITCHES Use only a weight carrying hitch de-
signed for the total trailer weight.
Toyota does not recommend using a
weight distribution (load equalizing)
hitch.
The hitch must be bolted securely to
the vehicle frame and installed accord-
ing to the hitch manufacturer ’s instruc-
tions.
If using a fifth wheel hitch, the center
of the king pin must be forward of the
axis of the vehicle’s rear wheels, and
installed according to the manufactur-
er ’s instructions.
The hitch ball and king pin should have
a light coat of grease.
Toyota recommends that the trailer
hitch, except fifth wheel hitch, be re-
moved when not towing to prevent inju-
ry and/or damage by the hitch in event
of a rear end collision. After removing
the hitch, the installation area should
be sealed to prevent entry of exhaust
fumes and mud.
NOTICE
Do not use an axle-mounting hitch as
it may cause damage to the axle
housing, wheel bearings, wheels and/
or tires.
BRAKES AND SAFETY CHAINS
Toyota recommends trailers with brakes
that conform to any applicable federal
and state/provincial regulations.
A safety chain must always be used
between the towing vehicle and the
trailer. Leave sufficient slack in the
chain for turns. The chain should cross
under the trailer tongue to prevent the
tongue from dropping to the ground in
case it becomes damaged or sepa-
rated. For correct safety chain proce-
dures, follow the hitch or trailer
manufacturer ’s recommendations.
CAUTION
If the total trailer weight exceeds
453 kg (1000 lb.), trailer brakes are
required.
Never tap into your vehicle’s hy-
draulic system as it would lower its
braking effectiveness.
Never tow a trailer without using a
safety chain securely attached to
both the trailer and the vehicle. If
damage occurs to the coupling unit
or hitch ball, there is danger of the
trailer wandering over into another
lane.
TIRES
Ensure that your vehicle’s tires are
properly inflated. See Chapter 7 −2 for
instructions.
The trailer tires should be inflated to
the pressure recommended by the trail-
er manufacturer in respect to the total
trailer weight.