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Steering in Emergencies
There are times when steering can be more effective
than braking. For example, you come over a hill and find
a truck stopped in your lane, or a car suddenly pulls
out from nowhere, or a child darts out from between
parked cars and stops right in front of you. These
problems can be avoided by braking — if you can stop
in time. But sometimes you cannot stop in time
because there is no room. That is the time for evasive
action — steering around the problem.
The vehicle can perform very well in emergencies like
these. First apply the brakes. SeeBraking on page 4-4.
It is better to remove as much speed as possible
from a collision. Then steer around the problem, to the
left or right depending on the space available.
An emergency like this requires close attention and
a quick decision. If holding the steering wheel at the
recommended 9 and 3 o’clock positions, it can be turned
a full 180 degrees very quickly without removing either
hand. But you have to act fast, steer quickly, and just as
quickly straighten the wheel once you have avoided the
object.
The fact that such emergency situations are always
possible is a good reason to practice defensive driving
at all times and wear safety belts properly.
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3. Remove the rubber
cap from the rear of
the chamber.
4. Put the release stud, nut and flat washer into the
chamber.
5. Turn the stud clockwise a quarter of a turn.6. Turn the stud nut
clockwise several turns
to release the brakes.
Follow the same
procedure to release
the other brake or
brakes.
7. At the repair facility, apply air pressure of at least
70 psi (480 kPa) to the brake chambers, either
from an external air supply or the vehicle’s
air system.
8. Turn the stud nut counterclockwise several turns.
Remove the stud from the chamber.
9. Replace the stud and washer and tighten the nut
into the side of the chamber.
10. Replace the rubber cap.
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5. Open the fuel filter vent
valve by turning the
screw counterclockwise
several full turns.
6. Repeatedly push down
on the fuel filter primer
pump with the palm of
your hand. Let the
pump return upward
between pushes.7. Operate the priming pump until a small amount of
fuel seeps from the vent valve. When fuel is seen,
the filter is full of fuel and the system should be
primed.
8. Close the vent valve.
9. Clean any fuel that accumulated on the fuel filter.
10. Start the engine and let it idle for a few minutes.
11. Check the filter for leaks.
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Priming the 7.8L Duramax®Diesel Engine
If the vehicle is equipped with the 7.8L Duramax®diesel
engine, use the following procedure to prime the engine:
1. Make sure there is fuel in the fuel tank.
2. Make sure the specified fuel filter is properly
installed.
3. Make sure the fuel lines are securely connected.4. Make sure the fuel filter is cool to the touch.
5. Use a clean cloth to remove dirt and oil from the
fuel filter head and breather valve.
6. Use the palm of your hand to repeatedly press
and release the plunger at the top of the fuel filter
priming pump. Continue until the plunger resistance
becomes firm. This may take from 20 to 100 times,
depending upon fuel tank location.
7. Turn the fuel filter breather valve screw
counterclockwise several turns to open the
breather valve.
8. Use the palm of your hand to repeatedly press and
release the plunger at the top of the fuel filter
priming pump until fuel begins to seep from the
breather valve.
9. Tighten the fuel filter breather screw to the specified
torque, 4.9Y(43 lbs. in.).
10. Use the palm of your hand to press and release the
plunger at the top of the fuel filter priming pump
about 20 more times. This sends fuel to the engine.
11. Use a clean cloth to remove any fuel from the fuel
filter and surrounding area.
12. Start the engine and allow it to idle for a few
minutes.
13. Check the fuel filter for leakage.
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4. Install the new filter element.
5. Reinstall and tighten the filter container and
reconnect the water sensor wire to the filter.
6. Use the fuel filter priming procedure earlier in this
section to prime the fuel filter.
7. Tighten the air bleed valve by turning it clockwise
until hand-tight.
8. Start the engine and let it idle for five minutes.
Check the fuel filter and air bleed valve for leaks.
How to Reset Fuel Filter Change
Light - DURAMAX 6.6L (LMM) Engine
The engine controller calculates when to change the fuel
filter based on vehicle and fuel use. Whenever the
fuel filter is changed, reset the fuel filter light so
the engine controller can calculate when the next fuel
filter change is required. If the fuel filter is ever changed
prior to a change fuel filter light being turned on,
reset the fuel filter change light.To reset the Fuel Filter Change light:
1. Turn the ignition key to ON/RUN with the engine off
2. Fully press the accelerator and brake pedals at the
same time for 10 seconds. If the Fuel Filter Change
light flashes for 5 seconds, the system is resetting.
3. Turn the key to OFF.
If the Fuel Filter Change light comes back on when you
start the vehicle, the light has not been reset. Repeat
the procedure. SeeChange Fuel Filter Warning Light on
page 3-45for more information.
Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel might be hard
to find. Never use leaded gasoline or any other fuel
not recommended in the previous text on fuel. Costly
repairs caused by use of improper fuel would not
be covered by the vehicle warranty.
To check the fuel availability, ask an auto club, or
contact a major oil company that does business in the
country where you will be driving.
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Filling the Tank
{CAUTION:
Fuel vapor is highly flammable. It burns violently,
and that can cause very bad injuries. Do not
smoke if you are near fuel or refueling the vehicle.
Keep sparks, flames and smoking materials away
from fuel.
The fuel cap can be on either or both sides of the
vehicle depending on option content.
To take off the cap, turn it slowly counterclockwise. Fuel caps for all
gasoline applications,
and all diesel between
frame rail fuel tank
applications
Fuel caps for all side
mounted diesel
applications
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{CAUTION:
If you get fuel on yourself and then something
ignites it, you could be badly burned. Fuel can
spray out on you if you open the fuel cap too
quickly. This spray can happen if the tank is nearly
full, and is more likely in hot weather. Open the
fuel cap slowly and wait for any “hiss” noise to
stop. Then unscrew the cap all the way.
When reinstalling the cap, turn it clockwise until it is
tight.
Notice:If you need a new fuel cap, be sure to get
the right type. Your dealer/retailer can get one
for you. If you get the wrong type, it may not fit
properly. This may cause the malfunction indicator
lamp to light and may damage the fuel tank and
emissions system. SeeMalfunction Indicator Lamp
on page 3-36.If the vehicle has dual tanks, fill the driver side tank,
or forward tank, first. The fuel gage will give better
readings this way. The gage will show the total fuel left
in both tanks.
If the vehicle is a C4/C5 model and has dual tanks, the
engine must be off when refueling or the fuel transfer
system may become inoperable.
If the vehicle has a single tank with dual fillers, where
there is a filler on each side of the vehicle, do not
attempt to fill the tank through both fillers at the same
time. Do not fill the tank with both caps removed or
over-filling the tank and fuel spillage can result.
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{CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol and
it will burn if the engine parts are hot enough. Do
not spill coolant on a hot engine.
1. You can remove the
coolant surge tank
pressure cap when
the cooling system,
including the coolant
surge tank pressure
cap and upper radiator
hose, is no longer hot.
Turn the pressure cap slowly counterclockwise
about one full turn. If you hear a hiss, wait for that to
stop. A hiss means there is still some pressure left.
2. Then keep turning the pressure cap slowly, and
remove it.3. Fill the coolant surge tank with the proper mixture,
to the FULL COLD mark.
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