When your engine is cold, let it run for a few minutes
before you move your vehicle. This lets oil pressure
build up. Your engine will sound louder when it’s cold.
Notice:If you are not in an idling vehicle and the
engine overheats, you would not be there to see the
overheated engine indication. This could damage
your vehicle. Do not let your engine run when you are
not in your vehicle.
Cold Weather Starting (Diesel Engine)
The following tips will help you get good starting in
cold weather.
Use the recommended engine oil when the outside
temperature drops below freezing. SeeEngine Oil on
page 5-21. When the outside temperature drops below
0° F (–18°C), use of the engine coolant heater is
recommended.
If you experience longer cranking times, notice an
unusual amount of exhaust smoke or are at higher
altitudes (over 7,000 ft. or 2 135 m), you may use your
engine coolant heater. SeeEngine Coolant Heater
on page 2-8.
SeeDiesel Fuel Requirements and Fuel System on
page 5-2for information on what fuel to use in cold
weather.
If Your Diesel Engine Won’t Start
If you’ve run out of fuel, look atRunning Out of Fuel
on page 5-11. SeeDiesel Fuel Requirements and Fuel
System on page 5-2.
If you’re not out of fuel, and your engine won’t start,
do this:
Turn your ignition key to RUN. Immediately after the wait
to start light goes off, turn the ignition key to START.
If the light doesn’t go off, wait a few seconds, then try
starting your engine again. See your dealer as soon
as you can for a starting system check.
If the light comes on and then goes off and you know your
batteries are charged, but your engine still won’t start,
your vehicle needs service.
If the light does not come on when the engine is cold,
your vehicle needs service.
If your batteries don’t have enough charge to start your
engine, see “Battery” in the owner’s manual Index.
Be sure you have the right oil for your engine, and that
you’ve changed the oil at the proper times. If you use
the wrong oil, your engine may be harder to start.
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Oil Pressure GageThe oil pressure gage shows the engine oil pressure in
psi (pounds per square inch) when the engine is running.
Canadian vehicles indicate pressure in kPa (kilopascals).
Oil pressure may vary under different driving conditions
and oil types. The DURAMAX
®engine may generate
oil pressure in excess of 80 psi (548 kPa) under certain
conditions, especially in cold temperatures. This is a
normal operating range.
{CAUTION:
Do not keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Lack of proper engine oil maintenance may
damage the engine. The repairs would not be covered
by your warranty. Always follow the maintenance
schedule in this manual for changing engine oil. United States
(Pickup Models)Canada
(Pickup Models)
United States
(Van Models)Canada
(Van Models)
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Towing
Towing a Trailer
When towing at high altitude on steep uphill grades,
consider the following:
Engine coolant will boil at a lower temperature than sea
level. If you turn your engine off immediately after towing
at high altitude on steep uphill grades, your vehicle may
show signs similar to engine overheating.To avoid this, let the engine run while parked (preferably
on level ground) with automatic transmission equipped
vehicles in PARK (P) or manual transmission equipped
vehicles in NEUTRAL with the park brake applied for at
least five minutes before turning the engine off. If you do
get the overheat warning, seeEngine Overheating on
page 5-39.
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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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A. Battery
B. Coolant Surge Tank
C. Automatic Transmission Dipstick
D. Engine Fan
E. Engine Air Cleaner/Filter
F. Engine Oil Fill Cap
G. Power Steering Fluid Reservoir
H. Brake Fluid Reservoir
I. Windshield Washer Fluid Reservoir
Engine Oil
Checking Engine Oil
It is a good idea to check your engine oil level every
time you get fuel.
The engine oil dipstick handle is a yellow loop.
SeeEngine Compartment Overview on page 5-18
for the location of the engine oil dipstick.In order to get an accurate reading, the oil must be
warm, at normal operating temperature, and the vehicle
must be on level ground.
1. Turn off the engine and give the oil at least
five minutes to drain back into the oil pan. With a
cool engine, allow 30 minutes. If you do not do this,
the oil dipstick might not show the actual level.
2. Pull out the dipstick and clean it with a paper towel
or a cloth, then push it back in all the way. Remove
it again, keeping the tip down.
When to Add Engine Oil
If the oil is below the cross-hatched area at the tip of the
dipstick, you will need to add at least two quarts/liters of
oil. But you must use the right kind. This section explains
what kind of oil to use. For engine oil crankcase capacity,
seeSpeci cation Charts on page 5-50.
Notice:Do not add too much oil. If the engine
has so much oil that the oil level gets above the
cross-hatched area that shows the proper operating
range, the engine could be damaged.
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•SAE 15W-40
As shown in the viscosity chart, SAE 15W-40 is
best for your vehicle. However, you can use
SAE 10W-30 at temperatures above 0°F (−18°C).
When it is very cold, below 0°F (−18°C), you should
use SAE 5W-40 to improve cold starting. 5W-40
is not recommended for use at high temperatures,
above 100°F (38°C).
These numbers on the oil container show its
viscosity, or thickness. Do not use other viscosity
oils such as SAE 10W-40 or SAE 20W-50.
This doughnut-shaped logo
(symbol) is used on most
oil containers to help you
select the correct oil. It
means that the oil has been
certified by the American
Petroleum Institute.
You should look for this on the oil container, and use
onlythose oils that display this logo.
GM Goodwrench
®oil of the recommended viscosity
grades meets all the requirements for your vehicle.
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Engine Oil Additives
Do not add anything to your oil. The recommended oils
with the API service symbol are all you will need for
good performance and engine protection.
Engine Oil Life System
When to Change Engine Oil
Your vehicle has a computer system that lets you know
when to change the engine oil and filter. This is based on
engine timing, engine load, and engine temperature, and
not on mileage. Based on driving conditions, the mileage
at which an engine 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 ENGINE OIL message in pickup models
or a change engine oil light in van models will come on.
Change your oil as soon as possible within the next
600 miles (1 000 km). 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. Your dealer has GM-trained service people who
will perform this work using genuine GM parts and reset
the system. 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.
How to Reset the Engine Oil Life
System
The Engine Oil Life System calculates when to change
your engine oil and filter based on vehicle use. Anytime
your oil is changed, reset the system so it can calculate
when the next oil change is required. If a situation occurs
where you change your oil prior to a CHANGE ENGINE
OIL message (pickup models) or a change engine oil light
(van models) being turned on, reset the system.
To reset the Engine Oil Life System, do the following:
1. Turn the ignition key to RUN with the engine off.
2. Fully press and release the accelerator pedal
three times within five seconds.
Pickup Models: If the OIL LIFE RESET message
flashes for 10 seconds, the system is resetting.
Van Models: If the change engine oil light flashes
for five seconds, the system is reset.
3. Turn the key to LOCK.
If the message or light comes back on when you start
your vehicle, the engine oil life system has not reset.
Repeat the procedure. If it still does not reset, see your
dealer for service.
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Automatic Transmission Fluid
When to Check and Change
(Pickup Models)
A good time to check your automatic transmission fluid
level is when the engine oil is changed.
Change both the fluid and filter every 25,000 miles
(41 500 km) if the vehicle is mainly driven under one
or more of these conditions:
•In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
•In hilly or mountainous terrain.
•When doing frequent trailer towing.
•Uses such as found in taxi, police or
delivery service.
If you do not use your vehicle under any of
these conditions, change the fluid and filter
every 50,000 miles (83 000 km).
SeeScheduled Maintenance on page 6-4.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at the dealership service
department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
Notice:Too much or too little uid can damage your
transmission. Too much can mean that some of the
uid could come out and fall on hot engine part or
exhaust system parts, starting a re. Too little uid
could cause the transmission to overheat. Be sure
to get an accurate reading if you check your
transmission uid.
Wait at least 30 minutes before checking the
transmission fluid level if you have been driving:
•When outside temperatures are above 90°F (32°C).
•At high speed for quite a while.
•In heavy traffic — especially in hot weather.
•While pulling a trailer.
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