2007 GMC SIERRA change time

Getting Familiar with Off-Road Driving
It is a good idea to practice in an area that is
safe and close to home before you go into the
wilderness. Off-road driving does require some new
and different driving skills. Here is what we mean.
Tune your senses to different kinds of signals.
Your eyes, for example, need to constantly sweep
the terrain for unexpected obstacles. Your ears
need to listen for unusual tire or engine sounds.
With your arms, hands, feet, and body, you
will need to respond to vibrations and vehicle
bounce.
Controlling your vehicle is the key to successful
off-road driving. One of the best ways to
control your vehicle is to control your speed.Here are some things to keep in mind. At higher
speeds:You approach things faster and you have less
time to scan the terrain for obstacles.
You have less time to react.
You have more vehicle bounce when you
drive over obstacles.
You will need more distance for braking,
especially since you are on an unpaved
surface.
{CAUTION:
When you are driving off-road, bouncing
and quick changes in direction can easily
throw you out of position. This could
cause you to lose control and crash. So,
whether you are driving on or off the road,
you and your passengers should wear
safety belts.
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Towing a Trailer
If your vehicle has a diesel engine, see the
DURAMAX®Diesel manual for more information.
Do not tow a trailer during break-in. SeeNew
Vehicle Break-In on page 132for more information.
{CAUTION:
If you do not use the correct equipment
and drive properly, you can lose control
when you pull a trailer. For example, if the
trailer is too heavy, the brakes may not
work well — or even at all. You and your
passengers could be seriously injured. Pull
a trailer only if you have followed all the
steps in this section. Ask your dealer for
advice and information about towing a
trailer with your vehicle.Notice:Pulling a trailer improperly can
damage your vehicle and result in costly repairs
not covered by your warranty. To pull a trailer
correctly, follow the advice in this part, and see
your dealer for important information about
towing a trailer with your vehicle.
To identify the trailering capacity of your vehicle,
you should read the information in “Weight of
the Trailer” that appears later in this section.
Trailering is different than just driving your vehicle
by itself. Trailering means changes in acceleration,
braking, handling, durability and fuel economy.
Successful, safe trailering takes correct equipment,
and it has to be used properly.
That’s the reason for this part. In it are many
time-tested, important trailering tips and safety
rules. Many of these are important for your safety
and that of your passengers. So please read
this section carefully before you pull a trailer.
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Manual Trailer Brake Apply
The Manual Trailer Brake Apply Lever is located on
the Trailer Brake Control Panel and is used to apply
the trailer’s electric brakes independent of your
vehicle’s brakes. This lever is used in the Trailer
Gain Adjustment Procedure to properly adjust the
power output to the trailer brakes. Sliding the lever
to the left will apply only the trailer brakes. The
power output to the trailer is indicated in the Trailer
Brake Display Page in the DIC. If your vehicle’s
service brakes are applied while using the Manual
Trailer Brake Apply Lever, the trailer output power
will be the greater of the two.
The trailer and the vehicle’s brake lamps will come
on when either vehicle braking or manual trailer
brakes are applied.
Trailer Gain Adjustment Procedure
Trailer Gain should be set for a specic trailering
condition and must be adjusted any time
vehicle loading, trailer loading or road surface
conditions change.
Setting the Trailer Gain properly is needed for the
best trailer stopping performance. A trailer that
is over-gained may result in locked trailer brakes.
A trailer that is under-gained may result in notenough trailer braking. Both of these conditions
may result in poorer stopping and stability of
the vehicle and trailer.
Use the following procedure to correctly adjust
Trailer Gain for each towing condition:
1. Make sure the trailer brakes are in proper
working condition.
2. Connect a properly loaded trailer to the
vehicle and make all necessary mechanical
and electrical connections. SeeLoading Your
Vehicle on page 425for more information.
3. After the electrical connection is made to a
trailer equipped with electric brakes:
A TRAILER CONNECTED message will be
briey displayed on the DIC display.
The Trailer Brake Display Page will appear
on the DIC showing TRAILER GAIN and
TRAILER OUTPUT.
In the Trailer Output display on the
DIC, “------“will disappear if there is no
error present. Connecting a trailer without
electric brakes will not clear the six dashed
lines.
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4. Adjust the Trailer Gain by using the gain
adjustment (+ / -) buttons on the Trailer
Brake Control Panel.
5. Drive the vehicle with the trailer attached on a
level road surface representative of the towing
condition and free of traffic at about 20 to
25 mph (32 to 40 km/h) and fully apply
the Manual Trailer Brake Apply lever.
Adjusting trailer gain at speeds lower than
20 to 25 mph (32 to 40 km/h) may result in an
incorrect gain setting.
6. Adjust the Trailer Gain to just below the point
of trailer wheel lock-up, indicated by trailer
wheel squeal or puffs of tire smoke when
a trailer wheel locks.
Trailer wheel lock-up may not occur if towing
a heavily loaded trailer. In this case, adjust
the Trailer Gain to the highest allowable
setting for the towing condition.
7. Re-adjust Trailer Gain any time vehicle
loading, trailer loading or road surface
conditions change or if you notice trailer wheel
lock-up at any time while you are towingOther ITBC Related DIC Messages
In addition to displaying TRAILER GAIN and
TRAILER OUTPUT through the DIC, trailer
connection and ITBC system status is displayed in
the DIC.
TRAILER CONNECTED – This message will be
briey displayed when a trailer with electric brakes
is rst connected to the vehicle. This message
will automatically turn off in about ten seconds.
The driver can also acknowledge this message
before it automatically turns off.
CHECK TRAILER WIRING – This message will be
displayed if:
1. The ITBC system rst determines connection
to a trailer with electric brakes and then the
trailer harness becomes disconnected
from the vehicle.
If the disconnect occurs while the vehicle is
stationary, this message will automatically turn
off in about thirty seconds. This message
will also turn off if the driver acknowledges this
message off or if the trailer harness is
re-connected.
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To ensure quick starts in the wintertime, the E85
fuel must be formulated properly for your
climate according to ASTM specication D 5798.
If you have trouble starting on E85, it could
be because the E85 fuel is not properly formulated
for your climate. If this happens, switching to
gasoline or adding gasoline to the fuel tank can
improve starting. For good starting and heater
efficiency below 32°F (0°C), the fuel mix in the fuel
tank should contain no more than 70% ethanol.
It is best not to alternate repeatedly between
gasoline and E85. If you do switch fuels, it
is recommended that you add as much fuel as
possible — do not add less than three gallons
(11 L) when refueling. You should drive the vehicle
immediately after refueling for at least seven miles
(11 km) to allow the vehicle to adapt to the
change in ethanol concentration.
E85 has less energy per gallon than gasoline, so
you will need to rell the fuel tank more often
when using E85 than when you are using gasoline.
SeeFilling the Tank on page 493.Notice:Some additives are not compatible
with E85 fuel and can harm your vehicle’s fuel
system. Damage caused by additives would
not be covered by your new vehicle warranty.
Notice:Your vehicle was not designed for
fuel that contains methanol. Do not use
fuel containing methanol. It can corrode metal
parts in the fuel system and also damage
plastic and rubber parts. That damage would
not be covered under your warranty.
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 nd. 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 your
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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Notice:Use only engine oil identied as
meeting GM Standard GM6094M and showing
the American Petroleum Institute Certied
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 of extreme cold, where the
temperature falls below−20°F (−29°C), it is
recommended that you use either an SAE 5W-30
synthetic oil or an SAE 0W-30 oil. Both provide
easier cold starting and better protection for
the engine at extremely low temperatures.
Engine Oil Additives
Do not add anything to the oil. The recommended
oils with the starburst symbol that meet GM
Standard GM6094M are all you 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 lter.
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 ENGINE OIL SOON
message will come on. SeeDIC Warnings
and Messages on page 279. 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
lter must be changed at least once a year and
at this time the system must be reset.
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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 lter 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 SOON message coming on, reset the system.Always reset the engine oil life to 100% after
every oil change. It will not reset itself. To reset
the Engine Oil Life System, do the following:
1. Display the OIL LIFE REMAINING on the DIC.
If your vehicle does not have DIC buttons, the
vehicle must be in PARK (P) to access this
display. SeeDIC Operation and Displays (With
DIC Buttons) on page 268orDIC Operation
and Displays (Without DIC Buttons) on
page 275.
2. Press and hold the SET/RESET button on
the DIC, or the trip odometer reset stem if
your vehicle does not have DIC buttons,
for more than ve seconds. The oil life will
change to 100%.
If the CHANGE ENGINE OIL SOON message
comes back on when you start your vehicle, the
Engine Oil Life System has not reset. Repeat
the procedure.
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Brake Pedal Travel
See your dealer/retailer if the brake pedal does
not return to normal height, or if there is a
rapid increase in pedal travel. This could be a sign
that brake service might be required.
Brake Adjustment
Every time you make a brake stop, the brakes
adjust for wear.
Replacing Brake System Parts
The braking system on a vehicle is complex. Its
many parts have to be of top quality and work well
together if the vehicle is to have really good
braking. Your vehicle was designed and tested
with top-quality brake parts. When you replace
parts of the braking system — for example, when
the brake linings wear down and you need
new ones put in — be sure you get new approved
replacement parts. If you do not, the brakesmight not work properly. For example, if someone
puts in brake linings that are wrong for your
vehicle, the balance between the front and rear
brakes can change — for the worse. The braking
performance you have come to expect can
change in many other ways if someone puts in the
wrong replacement brake parts.
Battery
Your vehicle has a maintenance free battery.
When it is time for a new battery, get one that has
the replacement number shown on the original
battery’s label. We recommend an ACDelco
®
replacement battery. SeeEngine Compartment
Overview on page 498for battery location.
Warning:Battery posts, terminals, and related
accessories contain lead and lead compounds,
chemicals known to the State of California
to cause cancer and reproductive harm. Wash
hands after handling.
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