4-14
Watch for traffic signs, pavement markings and lines.
If you can see a sign up ahead that might indicate a
turn or an intersection, delay your pass. A broken
center line usually indicates it's all right to pass
(providing the road ahead is clear). Never cross a
solid line on your side of the lane or a double
solid line, even if the road seems empty of
approaching traffic.
Do not get too close to the vehicle you want to
pass while you're awaiting an opportunity. For one
thing, following too closely reduces your area of
vision, especially if you're following a larger
vehicle. Also, you won't have adequate space if the
vehicle ahead suddenly slows or stops. Keep back a
reasonable distance.
When it looks like a chance to pass is coming up,
start to accelerate but stay in the right lane and don't
get too close. Time your move so you will be
increasing speed as the time comes to move into the
other lane. If the way is clear to pass, you will have a
ªrunning startº that more than makes up for the
distance you would lose by dropping back. And if
something happens to cause you to cancel your pass,
you need only slow down and drop back again and
wait for another opportunity.If other cars are lined up to pass a slow vehicle, wait
your turn. But take care that someone isn't trying to
pass you as you pull out to pass the slow vehicle.
Check your mirrors and start your left lane change
signal before moving out of the right lane to pass.
When you are far enough ahead of the passed vehicle
to see its front in your right outside mirror, activate
your right lane change signal and move back into the
right lane. (Remember that if your right outside
mirror is convex, the vehicle you just passed may
seem to be farther away from you than it really is.)
Try not to pass more than one vehicle at a time
on two
-lane roads. Reconsider before passing the
next vehicle.
Don't overtake a slowly moving vehicle too rapidly.
Even though the brake lamps are not flashing, it may
be slowing down or starting to turn.
If you're being passed, make it easy for the
following driver to get ahead of you. Perhaps you
can ease a little to the right.
4-18
Driving in Rain and on Wet RoadsRain and wet roads can mean driving trouble. On a wet
road, you can't stop, accelerate or turn as well because
your tire
-to-road traction isn't as good as on dry roads.
And, if your tires don't have much tread left, you'll get
even less traction. It's always wise to go slower and be
cautious if rain starts to fall while you are driving. The
surface may get wet suddenly when your reflexes are
tuned for driving on dry pavement.
The heavier the rain, the harder it is to see. Even if your
windshield wiper blades are in good shape, a heavy rain
can make it harder to see road signs and traffic signals,
pavement markings, the edge of the road and even
people walking.
It's wise to keep your wiping equipment in good shape
and keep your windshield washer tank filled with
washer fluid. Replace your windshield wiper inserts
when they show signs of streaking or missing areas on
the windshield, or when strips of rubber start to separate
from the inserts.
4-29
Tie a red cloth to your mirror arm to alert police that
you've been stopped by the snow.
Put on extra clothing or wrap a blanket around you.
If you have no blankets or extra clothing, make body
insulators from newspapers, burlap bags, rags, floor
mats
-- anything you can wrap around yourself or
tuck under your clothing to keep warm.
You can run the engine to keep warm, but be careful.
CAUTION:
Snow can trap exhaust gases under your vehicle.
This can cause deadly CO (carbon monoxide) gas
to get inside. CO could overcome you and kill
you. You can't see it or smell it, so you might not
know it is in your vehicle. Clear away snow from
around the base of your vehicle if any is blocking
your exhaust pipe. And check around again from
time to time to be sure snow doesn't collect there.
Open a window just a little on the side of the
vehicle that's away from the wind. This will help
keep CO out.
Run your engine only as long as you must. This saves
fuel. When you run the engine, make it go a little faster
than just idle. That is, push the accelerator slightly. This
uses less fuel for the heat that you get and it keeps the
battery (or batteries) charged. You will need a
well
-charged battery (or batteries) to restart the vehicle,
and possibly for signaling later on with your headlamps.
Let the heater run for a while.
5-26
Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When
the clutch is engaged, the fan spins faster to provide
more air to cool the engine. In most everyday driving
conditions, the clutch is not fully engaged. This
improves fuel economy and reduces fan noise. Under
heavy vehicle loading, trailer towing and/or high outside
temperatures, the fan speed increases when the clutch
engages. So you may hear an increase in fan noise.
This is normal and should not be mistaken as the
transmission slipping or making extra shifts. It is merely
the cooling system functioning properly. The fan will
slow down when additional cooling is not required and
the clutch disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch disengages.
If a Tire Goes Flat
It's unusual for a tire to ªblow outº while you're driving,
especially if you maintain your tires properly. If air goes
out of a tire, it's much more likely to leak out slowly.
But if you should ever have a ªblowout,º here are a few
tips about what to expect and what to do:
If a front tire fails, the flat tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel firmly.
Steer to maintain lane position, and then gently brake to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you'd use in a
skid. In any rear blowout, remove your foot from the
accelerator pedal. Get the vehicle under control by
steering the way you want the vehicle to go. It may be
very bumpy and noisy, but you can still steer. Gently
brake to a stop
-- well off the road if possible.
If a tire goes flat, avoid further tire and wheel damage
by driving slowly to a level place and turn on your
hazard warning flashers. The next part tells you what
to do.
6-6 What Fuel to Use
In the United States, for best results use Number 2-D
diesel fuel year
-round (above and below freezing
conditions) as oil companies blend Number 2
-D fuel to
address climate differences. Number 1
-D diesel fuel
may be used in very cold temperatures (when it stays
below 0F or
-18C); however, it will produce a power
and fuel economy loss. Avoid the use of Number 1
-D
diesel fuel in warm or hot climates. It may result in
stalling, poor starting when the engine is hot and may
damage the fuel injection system.
At a minimum, the diesel fuel you use should meet
specifications ASTM D975
-00 (Grade Low Sulfur) in
the United States. In addition, the Engine Manufacturers
Association (EMA) has identified properties of an
improved diesel fuel for better engine performance and
durability. Diesel fuels corresponding to the EMA
Recommended Guideline on Premium Diesel Fuel
(FQP
-1A) could provide better starting, less noise and
better vehicle performance. If there are questions about
the fuel you are using, contact your fuel supplier.Diesel fuel may foam when you fill your tank. This can
cause the automatic pump nozzle to shut off, even
though your tank isn't full. If this happens, just wait for
the foaming to stop and then continue to fill your tank.
CAUTION:
Heat coming from the engine may cause the fuel
to expand and force the fuel out of your tank. If
something ignites the fuel, a fire could start and
people could be burned. To help avoid this, fill
your fuel tank only until the automatic nozzle
shuts off. Don't try to ªtop it off.º
6-10
To drain water, do the following:
1. Stop and park the vehicle in a safe place. Turn off
the engine and apply the parking brake.
2. Remove the fuel cap.
3. Place a fuel
-resistant container under the fuel filter.
The filter drain valve is located on the bottom of the
fuel filter. The fuel filter is located in the engine
compartment on the passenger's side of the vehicle,
or on the driver's side frame rail near the engine.
4. Open the drain valve by
turning two to three
turns. When fuel
empties from the valve,
all the water has been
drained. Close the valve
hand tight.5. Remove the fuel
-resistant container and properly
dispose of the contaminated fuel. To find out how to
properly dispose of contaminated diesel fuel, see
ªWhat to Do with Used Oilº in the ªEngine Oil
(Diesel Engines)º part, later in this section.
6. Install the fuel cap.
7. Start the engine and let it run for a few minutes.
If the engine stalls, the fuel system may need to be
primed. While draining the water from the fuel filter,
air may enter the fuel system. If air has entered the
fuel system the fuel system will need to be primed.
Refer to ªFuel Primingº later in this section.
If the water in fuel indicator comes on again after
driving a short distance or the engine runs rough or
stalls, a large amount of water has probably been
pumped into the fuel tank. The fuel tank should
be purged.
Fuel Priming
In order for the DURAMAX diesel engine fuel system
to work properly, the fuel lines must be full of fuel and
contain no air. If air gets into the fuel lines, it will be
necessary to prime the fuel lines to eliminate air before
operating the vehicle.
6-25
As in the chart shown previously, SAE 5W-30 is best for
your vehicle. However, you can use SAE 10W
-30 if it's
going to be 0F (
-18C) or above. These numbers on
an oil container show its viscosity, or thickness. Do not
use other viscosity oils, such as SAE 20W
-50.
NOTICE:
Use only engine oil with the American Petroleum
Institute Certified For Gasoline Engines
starburst symbol. Failure to use the
recommended oil can result in engine damage not
covered by your warranty.
GM Goodwrench oil meets all the requirements for
your vehicle.
If you are in an area where the temperature falls
below
-20F (-29C), consider using either an
SAE 5W
-30 synthetic oil or an SAE 0W-30 oil. Both
will provide easier cold starting and better protection for
your engine at extremely low temperatures.
Engine Oil Additives
Don't add anything to your oil. The recommended oils
with the starburst symbol are all you will need for good
performance and engine protection.
When to Change Engine Oil
(GM Oil Life System)
Your vehicle has a computer system that lets you know
when to change the engine oil and filter. This is based on
engine revolutions and engine temperature, and not on
mileage. Based on driving conditions, the mileage at
which an oil change will be indicated can vary
considerably. For the oil life system to work properly,
you must reset the system every time the oil is changed.
When the system has calculated that oil life has been
diminished, it will indicate that an oil change is
necessary. A change oil light will come on. Change your
oil as soon as possible within the next two times you
stop for fuel. It is possible that, if you are driving under
the best conditions, the oil life system may not indicate
that an oil change is necessary for over a year. However,
your engine oil and filter must be changed at least once
a year and at this time the system must be reset. It is also
important to check your oil regularly and keep it at the
proper level.
If the system is ever reset accidentally, you must change
your oil at 3,000 miles (5 000 km) since your last oil
change. Remember to reset the oil life system whenever
the oil is changed.
6-78 Headlamp Wiring
The headlamp wiring is protected by a circuit breaker in
the light switch. An electrical overload will cause the
lights to go on and off, or in some cases to remain off.
If this happens, have your headlamp wiring checked
right away.
Windshield Wiper Fuses
The windshield wiper motor is protected by a circuit
breaker inside the motor and a circuit breaker or fuse in
the fuse block. If the motor overheats, the wipers will
stop until the motor cools. If the overload is caused by
an electrical problem, be sure to get it fixed.
Fusible Links
A fusible link is a short piece of wire several gauge sizes
smaller than the circuit it protects. It will melt in an
overload situation, opening the circuit.
Your starter and other circuits have these fusible links.
The size is printed on the insulation. If the insulation is
burned beyond recognition, consult your GM dealer for
the proper size. Replace a fusible link with one of the
same size and insulation type. Fusible link insulation is a
special purpose high
-temperature material.
The hydraulic brake booster motor feed circuit and
starter circuit are protected by a fusible link. Vehicles
with a diesel engine have a fusible link for the intake
heater feed circuit.