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Driving and Operating 131
Warning (Continued)
on the exhaust brake and shift the
transmission to the next lower
gear. This will help control your
speed. Do not hold the brake
pedal down too long or too often
while going down a steep or long
grade. This could cause the
brakes to get hot and not to work
as well. As a result, the truck will
not slow down at the usual rate.
Failure to take these steps could
result in loss of vehicle control.
You and others could be seriously
injured.
Brake Effectiveness When the
Vehicle Has Been Driven on a
Flooded Road or Washed
{Warning
When the vehicle is driven on a
flooded road, parked on a flooded
road or washed, water can get(Continued)
Warning (Continued)
into the brakes and reduce their
effectiveness. If the brakes do not
work well afterward, drive slowly
and gently press the brake pedal
several times until the brakes dry
out and start working normally.
Always do this after driving
through water or washing the
vehicle to help reduce the risk of
personal injury. Before parking
the vehicle in winter, press the
brake pedal several times in the
same way to get rid of moisture in
the brakes. Otherwise, the
moisture in the brakes may freeze
and make the vehicle immovable.
You and others could be seriously
injured.
If the vehicle must be driven on a
flooded road or is parked in an area
that becomes flooded, promptly
perform a check for the following
points:
. Effectiveness of the brakes .
Water-ingress or damage to
drum brakes, disc brakes
. Engine damage due to
water-ingress
. Shorting of electrical
components
. Oil level and degradation
(cloudiness) of the engine,
transmission, differential
. Greasing of each components
(lubrication)
Steering
Do Not Leave the Steering
Wheel Fully Turned for a
Long Time
{Warning
If you leave the steering wheel
fully turned for a long time, the oil
in the power steering oil pump will
become extremely hot. This
would cause poor lubrication, oil
tank damage and seal
deterioration, leading to power
(Continued)

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132 Driving and Operating
Warning (Continued)
steering oil pump damage, power
steering unit damage and power
steering hose damage. As a
result the steering wheel could
become extremely hard to turn
and a fire or other accident could
occur.
You and others could be seriously
injured.
Steering Wheel
If the steering parts have excess
play or looseness or if any abnormal
condition is noted, have the steering
system checked immediately.
Driving on Wet Roads
Driving on Slippery Surface or
Driving in Bad Weather (Rain,
Icy Roads, Snowy Roads, etc.)
In bad weather, visibility is reduced
and slippery road surfaces increase
stopping distances. Drive more
slowly than you would in good
weather. Also, avoid sharp turns ofthe steering wheel and hard
braking. Use engine brakes together
with the foot brakes to decelerate.
Using the exhaust brake on a
slippery road surface could cause
the tires to slip.
You may not realize the surface is
slippery until the vehicle is skidding.
Learn to recognize warning clues—
such as enough water or ice on the
road to make a "mirrored surface"—
and slow down when there is any
doubt.
There is a risk of hydroplaning,
particularly where water tends to
collect on the road surface. Drive at
speeds that allow you to stay in
complete control.
If you cannot avoid driving on a
flooded road, first check the depth
of the water and then drive through
the water at a slow, constant speed.
There is a risk that water will get
into the engine's cylinders and
cause engine damage (water
hammering). Keep your speed
down, and drive with great care.
Hydroplaning :
If a vehicle is driven
at high speed on a road that is
covered with water, a layer of water
can form between the tires and road
surface, causing the tires to lose
their grip and slide across the water.
This phenomenon is called
hydroplaning. It is dangerous
because it makes the steering
wheel and brakes useless.
Refer to Wheels and Tires 0272.
Hill and Mountain Roads
Narrow or Congested Roads
When passing or overtaking a
vehicle on a narrow mountain road
or on a narrow or congested urban
road, pay careful attention to
obstacles on either side and to the
condition of the shoulder of
the road.
When turning, the rear wheels will
follow tighter curves than the front
wheels. Use the mirrors to confirm
safety.

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172 Driving and Operating
.Any substance other than the
DEF may cause a breakdown to
the SCR system.
. Use the DEF handling
equipment made of correct
materials (Polyethylene or
Stainless-steel).
. Avoid contamination from using
dirty funnel for filling.
. If a fluid other than the specified
DEF is mistakenly added,
incorrect fluid may cause a
failure. Have it inspected and
serviced at a dealer immediately.
. Ammonia odor may be
generated when the DEF is
exposed to high temperature.
. Do not add DEF above the F
position on the level gauge. DEF
may leak from the breather hose
while driving. Also, the sensor
may be broken when DEF
freezes.
. Do not put your feet on or stand
on the DEF tank. The tank, pipe
or sensors may be damaged. .
After stopping the engine, a flow
sound may be heard from the
DEF tank or DEF supply pump.
This sound occurs as the DEF in
the piping is returning to the
tank, and does not indicate an
abnormality.
See Winter Driving 0133.
Adding DEF
1. Turn the engine control switch to the ACC or LOCK position
and make sure to stop the
engine.
2. Wipe off dust or dirt from around the filler port of the
DEF tank. 3. Turn and remove the filler cap.
4. Refill the tank up to the F
position in the level gauge on
the front face of the tank. The
DEF may overflow from the
filler port if it is added in excess
of the F position.
5. Tighten the cap after refilling is completed.
6. Wipe off DEF that is spilled at refilling.
{Warning
On occasion, you may notice an
odor when the DEF tank is
opened. Do not sniff the filler
port, etc.
When refilling the DEF tank:
Failure to follow the above
instructions could result in a fire
or a breakdown of the selective
catalytic reduction (SCR) system.
Do not dilute DEF with water.
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174 Driving and Operating
the engine is running. The vehicle
can be driven normally when DEF is
frozen in the DEF tank.
If the Refill DEF warning light is on
and the remaining DEF in the DEF
tank is frozen, the vehicle low level
warning system cannot be reset by
adding DEF. The DEF gauge will not
register correctly should the
remaining DEF freeze at this level.
Move the vehicle to a location to
allow the DEF to thaw. Once the
DEF is thawed the DEF gauge
should read correctly allowing the
low level warning system to reset.
To avoid this condition follow the
instructions for Adding DEF in Cold
Weather.
{Warning
Do not warm up the DEF tank
using a burner, heater, etc. You
and others could be seriously
injured.DEF Storage
Seal the container and store it in an
indoor place with good ventilation
avoiding direct sunlight.
When storing DEF, the shelf life
varies depending on the room
temperature of the storage place.
For details, please contact the
distributor of the DEF.
For storage of DEF, seal the
container to prevent the moisture
from evaporating.
Even when DEF has been frozen,
its quality is maintained when it is
thawed. It can be used as it is.
To store or carry DEF, use the
original container in which the DEF
was kept at the time of purchase.
Also, if other containers are used,
prepare a clean container for
exclusive use, which can be a
polyethylene resin tank (PE) or
stainless steel container, and do not
introduce foreign matter such as
water or contamination. DEF Disposal
Do not dispose of DEF and the
empty container into lakes, marine
areas, rivers, etc. DEF must be
disposed of in a method conforming
to the regulatory requirements in
your state.
Selective Catalytic Reduction
(SCR) System
The Selective Catalytic Reduction
(SCR) system reduces nitrogen
oxide (NOx) emissions emitted from
a diesel engine. The SCR system
reduces NOx by adding (injecting)
Diesel Exhaust Fluid (DEF) into the
exhaust system and inducing a
reaction converting NOx into water
vapor and nitrogen.
The SCR system consists of the
DEF tank, DEF Control Unit, DEF
Supply Pump and Injector, and the
SCR Catalyst. It is important to keep
a good supply of DEF in the DEF
tank at all times. Monitor the DEF
gauge to be sure the DEF tank level
does not become too low.

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Driving and Operating 175
If the DEF level becomes too low or
incorrect fluid is added to the DEF
tank, the warning buzzer will sound,
warning and indicator lights will
come on and engine power will be
reduced. If you see these warning
and indicator lights, add DEF as
soon as possible or have your
vehicle serviced as soon as
possible.
Continuing to drive for too long after
these lights come on will result in
additional warnings, more engine
power reduction and will eventually
result in a severe vehicle speed
limitation. See“Diesel Exhaust
Fluid (DEF) Low Level Warning” and
“Incorrect Diesel Exhaust Fluid
(DEF)/SCR System Malfunction
Warnings” later in this section.
{Warning
Do not touch the water that
comes out from the muffler. The
water is mildly acidified due to the
action of oxidation catalyst inside
the muffler. In the event that the
(Continued)
Warning (Continued)
fluid does come into contact with
your skin, completely wash it off
with water. You and others could
be seriously injured.
Do not relocate or modify the
exhaust pipe, muffler, DPF, SCR,
or DEF tank, which may affect the
exhaust gas cleaning performance.
If any relocation or modification is
necessary, consult your dealer.
The SCR system continues to
operate for approximately 3 minutes
after the engine control switch is
turned to the "LOCK" position. It is
normal to hear a buzzing type noise
from the DEF supply pump
(mounted on the left side frame rail
behind the cab) during the
shutdown process.
If it is necessary to disconnect the
batteries for any reason, be sure to
wait at least 3 minutes after turning
the engine control switch to the
"LOCK" position. This will allow the SCR system to properly complete
its shutdown processes. See
Winter
Driving 0133.
Diesel Exhaust Fluid (DEF) Low
Level Warning
Diesel Exhaust Fluid (DEF) is a
required fluid for the operation of
your diesel engine just as diesel fuel
is required. To avoid running out of
DEF your vehicle will turn on
warning and indicator lights and
reduce engine power in progressive
stages to encourage adding DEF.
The following is a summary of the
diesel exhaust fluid (DEF) low level
warning lights, indicator lights and
engine power reductions.
Continuing to drive for too long after
these lights come on will eventually
result in a severe vehicle speed
limitation.
These warning and indicator lights
will go out automatically and engine
power will be restored to normal
after the SCR system detects that
the DEF tank is refilled with DEF.

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206 Driving and Operating
Exhaust Brake Function
Diesel Vehicles Equipped with
Exhaust Brake-interlocked Cruise
Automatic activation of the exhaust
brake during cruise control driving
suppresses an increase in the
speed on a downhill slope,
decreasing the need for the driver to
apply the regular brake pedal. The
exhaust brake does not activate
when the exhaust brake switch is
turn off.
The maximum slope angle at which
the system can control the vehicle
speed increase is different
depending on the load the vehicle is
carrying.
Automatic Activation and
Automatic Release of Exhaust
Brake
The exhaust brake is engaged when
the vehicle speed exceeds the set
speed on a downhill slope.
The exhaust brake is disengaged
when the vehicle slows down close
to the set.
Fuel
Fuel for Diesel Engines
Diesel Fuel Requirement and
Fuel System
Fuel Requirements
Use of fuels other than ultra
low-sulfur fuel may not conform to
emission regulations.
The fuel supply pump, injector or
other parts of the fuel system and
engine can be damaged if you use
any fuel or fuel additive other than
those specifically recommended by
the dealer.
To help avoid fuel system or engine
damage, pay attention to the
following:
.Some service stations mix used
engine oil with diesel fuel. Some
manufacturers of large diesel
engines allow this; however, for
your diesel engine, do not use
diesel fuel which has been
contaminated with engine oil.
Besides causing engine
damage, such fuel can also affect emission control. Before
using any diesel fuel, check with
the service station operator to
see if the fuel has been mixed
with engine oil.
. Do not use any fuel additive
(other than as recommended
under "Biocides" in Water in
Fuel 0209). At the time this
manual was printed, no other
fuel additive was recommended.
(See your authorized dealer to
find out if this has changed.)
. Take care not to run out of diesel
fuel. If you do run out of fuel,
you may need to bleed air out of
the supply pump to re-start the
engine after fuel has been filled.
Your vehicle is designed to use
either Number 1-D or Number 2-D
diesel fuel. However, for better fuel
economy, use Number 2-D diesel
fuel whenever possible. At
temperatures below -7 °C (20 °F),
Number 2-D fuel may pose
operating problems (see "Cold
Weather Operation" which follows).
At colder temperatures, use Number
1-D fuel (if available) or use a

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Driving and Operating 209
To reduce the risk of poor quality
fuel, purchase biodiesel blends from
a fuel supplier or fueling station
which sells BQ-9000 certified
biodiesel. See www.bq-9000.org for
a list of certified marketers.
Biodiesel Blends in Canada
Biodiesel blends that meet the CAN/
CGSB-3.522 specifications up to
20% (B20) can be used. Do not use
biodiesel blends above 20%, as
they may damage the engine and
fuel system.
Cold Weather Operation
Diesel fuel is sensitive to
temperature. All diesel fuel has a
certain amount of paraffin
components, which are high in
energy value and help improve fuel
economy. But, when temperatures
are below -7 °C (20 °F), the paraffin
components begin turning into wax
flakes. If temperatures are low
enough, these flakes can obstruct
the fuel filters and stop fuel from
reaching the engine.At low temperatures, wax flakes are
more likely to form in Number 2-D
fuel than in Number 1-D (or
"winterized" Number 2-D) fuel. For
best operation at temperatures
below -7 °C (20 °F), use Number
1-D, or Number 2-D which has been
blended with Number 1-D for winter
use. When temperatures are
consistently below (or near) -18 °C
(0 °F), use Number 1-D if at all
possible. Bear in mind, however,
that even Number 1-D fuel will form
wax flakes when temperatures are
extremely low.
Do not use home heating oil or
gasoline in your diesel engine;
either may cause engine damage.
The addition of kerosene will not
unplug a filter plugged with wax.
Warming a "waxed" filter to a
temperature of 0 °C to 10 °C (32 °F
to 50 °F) will return the wax to
solution. Filter replacement is not
normally required.
Water in Fuel
During refueling, it is possible for
water (and other contaminants) to
be pumped into your fuel tank along
with the diesel fuel. This can occur if
a service station does not regularly
inspect and clean its fuel tanks, or if
a service station receives
contaminated fuel from its
supplier(s).
To protect your engine from
contaminated fuel, there is a water
separator system on the engine
which allows you to drain excess
water from the fuel.
{Warning
The drained water/diesel fuel
mixture is flammable, and could
be hot. To help avoid personal
injury or death and/or property
damage, do not touch the fuel
coming from the water separator
drain valve, and do not expose
the fuel to open flames or sparks.
(Continued)

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Driving and Operating 211
Fuel will be mixed in the drained
water. Dispose of it in a method
conforming to the regulatory
requirements in your state.
If the water separator (fuel filter)
requires frequent draining, have the
fuel system inspected at your
dealer.
Pre Fuel Filter (Chassis-side)1. Attach a plastic hose to the drain plug (2) on the bottom of
the chassis-side fuel filter and
put the other end of the hose in
a container placed beneath the
filter. 2. Loosen the drain plug and
move the priming pump (1) up
and down by hand between
10 and 20 times.
3. Fully tighten the drain plug (2) and move the priming pump (1)
several times.
Fuel Filter (Engine-side)1. Attach a plastic hose to the drain plug (2) on the bottom of
the engine-side fuel filter (1)
and put the other end of the
hose in a container placed
beneath the filter.
2. Loosen the drain plug andmove the priming pump up and
down by hand between 10 and
20 times.
3. Fully tighten the drain plug and move the priming pump several
times.
4. Test run the engine and check that there are no fuel leaks
from the drain plug of the
engine-side fuel filter. Also
check that the water separator
(fuel filter) warning light
stays off.