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Diesel Fuel Requirements and Fuel System.......5-2
Diesel Engine Fuel.........................................5-2
What Fuel to Use...........................................5-3
Very Cold Weather Operation...........................5-5
Water in Fuel.................................................5-5
Water in Fuel Light Chart................................5-6
Running Out of Fuel.....................................5-11
Fuel Filter Replacement.................................5-12
Filling the Tank............................................5-15
Filling a Portable Fuel Container.....................5-17Checking Things Under the Hood....................5-18
Engine Compartment Overview.......................5-18
Engine Oil...................................................5-21
Engine Oil Life System..................................5-24
Engine Air Cleaner/Filter................................5-25
Automatic Transmission Fluid.........................5-29
Engine Coolant.............................................5-34
Radiator Pressure Cap..................................5-39
Coolant Surge Tank Pressure Cap..................5-39
Engine Overheating.......................................5-39
Cooling System............................................5-41
Capacities and Speci cations..........................5-50
Specification Charts......................................5-50
Section 5 Service and Appearance Care
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Diesel Fuel Requirements and
Fuel System
Some states and provinces have restrictions on the
purchase of diesel fuel for light-duty vehicles and require
you to buy permits or pay special taxes. Some of these
restrictions apply only to residents, and others apply
to both residents and visitors. These restrictions can
change. To learn the current restrictions in any state
or province, contact your auto club, the police or other
officials.
Diesel Engine Fuel
Notice:Diesel fuel or fuel additives not
recommended in this manual could damage your
fuel system, fuel-operated heater (FOH) (Van models
only) and engine. Your warranty would not cover
this damage. And:
Diesel fuel that has been mixed with engine oil
or automatic transmission uid could damage
your engine and emission controls.
Aftermarket diesel fuel additives are not tested
by General Motors. Some additives, particularly
those which contain alcohol or water emulsi ers,
may damage your fuel system. If you believe that
unique circumstances call for a fuel additive to
be used, consult your dealer for advice.
If you ever run out of diesel fuel, it can be difficult
to restart your engine. To avoid all this, never let
your tank get empty.
If gasoline is ever accidentally added to the fuel
tank, to avoid severe engine damage, do not run
the engine until the fuel tank can be drained.
If you run out of fuel,Running Out of Fuel on page 5-11
tells you how to restart your engine.
5-2
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What Fuel to Use
In the United States, for best results use No. 2-D diesel
fuel year-round (above and below freezing conditions)
as oil companies blend No. 2-D fuel to address climate
differences. No. 1-D diesel fuel may be used in very
cold temperatures (when it stays below 0°F or−18°C);
however, it will produce a power and fuel economy loss.
Avoid the use of No. 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 the
latest version of ASTM specification D 975 (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.It is acceptable to use diesel fuel containing up to 5%
biodiesel (B5), but the final blended fuel must meet the
same specification, ASTM D 975 (Grade Low Sulfur),
as other fuels used in your vehicle, and the biodiesel
used for making this fuel must meet the latest version of
ASTM specification D 6751. Biodiesel is produced from
vegetable oils or animal fat that have been chemically
modified to reduce the possibility of damage to your fuel
system and engine. Higher concentration (i.e., greater
than B5) biodiesel-containing fuels or the use of
unmodified bio-oils blended into diesel fuel at any
concentration is not recommended and could damage
your fuel system and engine. Such damage would not be
covered by your warranty. If there are questions about
the biodiesel-containing fuels you are using, contact your
fuel supplier.
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Diesel fuel may foam when you fill your tank. This can
cause the automatic pump nozzle to shut off, even
though your tank is not 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 re could start and
people could be burned. To help avoid this, ll
your fuel tank only until the automatic nozzle
shuts off. Do not try to top it off.
What Fuel to Use in Canada
Canadian fuels are blended for seasonal changes. Diesel
Type “A” fuel is blended for better cold weather starting
(below 0°F or−18°C); however, you may notice some
power and fuel economy loss. If Type “A” fuel is used in
warmer temperatures, stalling and hard starting may
occur. Diesel Type “B” fuel is blended for temperatures
above 0°F (−18°C). The emission control system requires
the use of diesel fuel with low-sulfur (.05% by weight)
content. Both low- and higher-sulfur fuels will be available
in Canada. Only low-sulfur diesel fuels are available in
the United States. It is important that diesel-powered
trucks are refueled only with low-sulfur fuel. Use of
fuels with higher-sulfur content will affect the function
of the emission components and may cause reduced
performance, excessive smoke, and unpleasant odor.
At a minimum, the diesel fuel you use should meet
the latest version of specification CAN/CGSB-3.517
(Low Sulfur Diesel) in Canada. In addition, the Engine
Manufacturers Association (EMA) has identified
properties of an improved diesel fuel for better engine
performance and durability (FQP-1A). Diesel fuels
corresponding to the EMA description could provide
better starting, less noise, and better vehicle
performance. If there are questions about the
fuel you are using, contact your fuel supplier.
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It is acceptable to use diesel fuel containing up to 5%
biodiesel (B5), but the final blended fuel must meet the
same specification, CAN/CGSB-3.517 (Low Sulfur
Diesel) in Canada, as other fuels used in your vehicle,
and the biodiesel used for making this fuel must meet the
latest version of ASTM specification D 6751. Biodiesel is
produced from vegetable oils or animal fat that have been
chemically modified to reduce the possibility of damage
to your fuel system and engine. Higher concentration
(i.e., greater than B5) biodiesel-containing fuels or the
use of unmodified bio-oils blended into diesel fuel at any
concentration is not recommended and could damage
your fuel system and engine. Such damage would not be
covered by your warranty. If there are questions about
the biodiesel-containing fuels you are using, contact your
fuel supplier.
Very Cold Weather Operation
Follow the instructions listed previously under the
heading “What Fuel to Use.”
Notice:Never use home heating oil or gasoline in
your diesel engine. They can cause engine damage.
In cold weather, your fuel filter may become clogged
(waxed). To unclog it, move the vehicle to a warm garage
area and warm the filter to between 32°F and 50°F
(0°C to 10°C). You will not need to replace it. Additional
information on the fuel filter follows.
Water in Fuel
{CAUTION:
Diesel fuel containing water is still ammable.
You could be burned. If you ever try to drain
water from your fuel, keep sparks, ames and
smoking materials away from the mixture.
Notice:If there is water in your diesel fuel and the
weather is warm or humid, fungus and bacteria can
grow in the fuel. They can damage your fuel system
and fuel operated heater (FOH) (if equipped). A diesel
fuel biocide can be used to sterilize your fuel system.
However, your fuel system may still need to be
cleaned. Your dealer can advise you of the
appropriate solution.
If your fuel tank needs to be purged to remove
water, see your dealer or a quali ed technician.
Improper purging can damage your fuel system
and block your FOH.
Sometimes, water can be pumped into your fuel tank
along with your diesel fuel. This can happen if a service
station doesn’t regularly inspect and clean its fuel tanks,
or if it gets contaminated fuel from its suppliers.
5-5
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If you have a pickup model and this happens, a WATER
IN FUEL message will appear on the Driver Information
Center (DIC). The water must be drained.
If you have a van model
and this happens, this
water in fuel warning
light will appear on the
instrument panel cluster.
The water must be drained from both chassis mounted
fuel filters. Your dealer can show you how to do this.Water in Fuel Light Chart
If the WATER IN FUEL DIC message or water in fuel
warning light comes on, use this chart.
Water In Fuel Light/Message Chart
Problem Recommended Action
Light/Message comes on
intermittently.Drain water from fuel
filter.
Light/Message stays on:
•At temperatures
above freezing.Drain fuel filter
immediately. If no water
can be drained and light
stays on, see your dealer
for assistance.
•At temperatures
below freezing.Drain fuel filter
immediately. If no water
can be drained — water
may be frozen in water
drain system. Water may
be frozen in the fuel lines.
Move the vehicle to a
warm location to thaw
out, and then drain filter
system.
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Water In Fuel Light/Message Chart
(cont’d)
Problem Recommended Action
•Immediately after
refueling, large
amount of water
possibly pumped
into fuel tank.Fuel tank purging
required. See your
dealer for assistance.
Notice:If you drive when this warning indicator is
on, you can damage your fuel injection system and
your engine. If the indicator comes on right after you
refuel, it means water was pumped into your fuel
tank. Turn off your engine immediately. Then, have
the water drained at once.
Hard starting, hesitation or flat performance at high speed
or during hard acceleration may be an indication of
premature fuel filter plugging due to dirty or contaminated
fuel. The filter element may need to be changed if this
happens. SeeFuel Filter Replacement on page 5-12.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(s). For pickup models, the filter drain valve
is located in the engine compartment, on the
passenger’s side of the vehicle, on the bottom of the
fuel filter. For van models, the filter drain valves for
the primary and secondary fuel filters are located in
the chassis (inside frame rail) compartment. They
are on the driver’s side of the vehicle, below the
fuel filters.
4. For pickup models,
open the drain valve
by turning it two to
three turns. When fuel
empties from the valve,
all the water has been
drained. Close the
valve hand tight. To
help remove all the
water, press the priming
pump several times.
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5. For van models, in order to drain the water from the
system, you will have to repeat the operation for the
primary and secondary fuel filters.6. Remove the fuel-resistant container and properly
dispose of the contaminated fuel. To find out how
to properly dispose of contaminated diesel fuel,
see “What to Do With Used Oil” underEngine Oil
on page 5-21.
7. Install the fuel cap.
8. For pickup models, 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. For van models, start the engine and let it
run for a few minutes.
If the WATER IN FUEL message/warning light 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.
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