2007 GMC SIERRA Owner's Manual

Four-Wheel-Drive Vehicles
Use the following procedure to tow your vehicle:
1. Shift the transmission to PARK (P).
2. Turn the engine off, but leave the ignition on.
3. Firmly set the parking brake.
4. Securely attach the vehicle being towed to the
tow vehicle.
{CAUTION:
Shifting a four-wheel-drive vehicle’s
transfer case into NEUTRAL can cause
your vehicle to roll even if the
transmission is in PARK (P). You or
others could be injured. Make sure the
parking brake is rmly set before you shift
the transfer case to NEUTRAL.
5. Shift the transfer case to NEUTRAL. See
Four-Wheel Drive on page 147for the
proper procedure to select the neutral position
for your vehicle.
6. Release the parking brake only after the
vehicle being towed is rmly attached to
the towing vehicle.
7. Turn the ignition off and leave the steering
column unlocked.
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Dolly Towing
Front Towing (Front Wheels Off the
Ground)
Two-Wheel-Drive Vehicles
Notice:If you tow a two-wheel-drive vehicle
with the rear wheels on the ground, the
transmission could be damaged. The repairs
would not be covered by your warranty. Never
tow your vehicle with the rear wheels on the
ground.
Two-wheel-drive vehicles should not be towed
with the rear wheels on the ground.
Two-wheel-drive transmissions have no provisions
for internal lubrication while being towed.
To dolly tow a two-wheel-drive vehicle, you must
tow the vehicle with the rear wheels on the
dolly. See “Rear Towing (Rear Wheels Off the
Ground)” later in this section for more information.
Four-Wheel-Drive Vehicles
Use the following procedure to tow your vehicle:
1. Drive the vehicle up onto the tow dolly.
2. Shift the transmission to PARK (P).
3. Turn the engine off, but leave the ignition on.
4. Firmly set the parking brake.
5. Securely attach the vehicle being towed to the
tow dolly.
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{CAUTION:
Shifting a four-wheel-drive vehicle’s
transfer case into NEUTRAL can cause
your vehicle to roll even if the
transmission is in PARK (P). You or
others could be injured. Make sure the
parking brake is rmly set before you shift
the transfer case to NEUTRAL.
6. Shift the transfer case to NEUTRAL. See
Four-Wheel Drive on page 147for the
proper procedure to select the neutral position
for your vehicle.
7. Release the parking brake only after the
vehicle being towed is rmly attached to
the towing vehicle.
8. Turn the ignition off and lock the steering
column.
Rear Towing (Rear Wheels Off the
Ground)
Two-Wheel-Drive Vehicles
Use the following procedure to tow your vehicle
from the rear:
1. Drive the vehicle onto the dolly.
2. Firmly set the parking brake. SeeParking
Brake on page 162.
3. Put the transmission in PARK (P).
4. Follow the dolly manufacturer’s instructions to
attach and secure the vehicle being towed to
the dolly and then the loaded dolly to the
tow vehicle. Make sure the wheels are straight
before towing.
Use an adequate clamping device to ensure
that the front wheels are locked into the
straight position.
5. Release the parking brake only after the
vehicle being towed is rmly attached to
the tow vehicle.
6. Turn the ignition to LOCK.
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Four-Wheel-Drive Vehicles
Use the following procedure to tow your vehicle
from the rear:
1. Drive the vehicle onto the dolly.
2. Firmly set the parking brake. SeeParking
Brake on page 162.
3. Put the transmission in PARK (P).
4. Follow the dolly manufacturer’s instructions to
attach and secure the vehicle being towed to
the dolly and then the loaded dolly to the
tow vehicle.
Use an adequate clamping device to ensure
that the front wheels are locked into the
straight position.{CAUTION:
Shifting a four-wheel-drive vehicle’s
transfer case into NEUTRAL can cause
your vehicle to roll even if the
transmission is in PARK (P). You or
others could be injured. Make sure the
parking brake is rmly set before you shift
the transfer case to NEUTRAL.
5. Shift the transfer case to NEUTRAL. See
Four-Wheel Drive on page 147.
6. Release the parking brake only after the
vehicle being towed is rmly attached to
the tow vehicle.
7. Turn the ignition to LOCK.
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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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If You Do Decide To Pull A Trailer
If you do, here are some important points:
There are many different laws, including speed
limit restrictions, having to do with trailering.
Make sure your rig will be legal, not only where
you live but also where you’ll be driving. A
good source for this information can be state
or provincial police.
Consider using a sway control. See “Hitches”
later in this section.
Don’t tow a trailer at all during the rst
500 miles (800 km) your new vehicle is driven.
Your engine, axle or other parts could be
damaged.
Then, during the rst 500 miles (800 km) that
you tow a trailer, don’t drive over 50 mph
(80 km/h) and don’t make starts at full throttle.
This helps your engine and other parts of your
vehicle wear in at the heavier loads.
You can tow in DRIVE (D). You may want to
shift the transmission to THIRD (3), or
FOURTH (4) with the Allison or Hydra-matic
6-speed transmissions, or if necessary, a lower
gear selection if the transmission shifts toooften, such as under heavy loads and/or hilly
conditions. SeeTow/Haul Mode Light on
page 266.
Three important considerations have to do with
weight:
The weight of the trailer
The weight of the trailer tongue
The weight on your vehicle’s tires
Tow/Haul Mode
Press this button at the end of the shift lever to
enable/disable the tow/haul mode.
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Tow/Haul is a feature that assists when pulling a
heavy trailer or a large or heavy load. See
Tow/Haul Mode on page 144for more information.
Tow/Haul is designed to be most effective when
the vehicle and trailer combined weight is at
least 75 percent of the vehicle’s Gross Combined
Weight Rating (GCWR). See “Weight of the
Trailer” later in the section. Tow/Haul is most
useful under the following driving conditions:
When pulling a heavy trailer or a large
or heavy load through rolling terrain.
When pulling a heavy trailer or a large or
heavy load in stop and go traffic.
When pulling a heavy trailer or a large or
heavy load in busy parking lots where
improved low speed control of the vehicle is
desired.
Operating the vehicle in Tow/Haul when lightly
loaded or with no trailer at all will not cause
damage. However, there is no benet to the
selection of Tow/Haul when the vehicle is
unloaded. Such a selection when unloaded may
result in unpleasant engine and transmissiondriving characteristics and reduced fuel economy.
Tow/Haul is recommended only when pulling a
heavy trailer or a large or heavy load.
Weight of the Trailer
How heavy can a trailer safely be?
It depends on how you plan to use your rig. For
example, speed, altitude, road grades, outside
temperature and how much your vehicle is used to
pull a trailer are all important. It can also depend
on any special equipment that you have on
your vehicle, and the amount of tongue weight the
vehicle can carry. See “Weight of the Trailer
Tongue” later in this section for more information.
Maximum trailer weight is calculated assuming
only the driver is in the tow vehicle and it has all
the required trailering equipment. The weight
of additional optional equipment, passengers and
cargo in the tow vehicle must be subtracted
from the maximum trailer weight.
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Use one of the following charts to determine how much your vehicle can weigh, based upon your vehicle
model and options.
C-1500 Regular Cab
Standard Box (2WD)*Axle Ratio Maximum Trailer Weight GCWR
4.3L V63.23
3.734,800 lbs (2 177 kg)
5,300 lbs (2 404 kg)9,500 lbs (4 309 kg)
10,000 lbs (4 536 kg)
4.8L V83.23
3.735,200 lbs (2 359 kg)
7,200 lbs (3 266 kg)10,000 lbs (4 536 kg)
12,000 lbs (5 443 kg)
5.3L V83.42
3.737,200 lbs (3 266 kg)
8,200 lbs (3 719 kg)12,000 lbs (5 443 kg)
13,000 lbs (5 897 kg)
*Fifth-wheel or gooseneck kingpin weight 15 percent to 25 percent of trailer weight up to 1,500 lbs (680 kg)
maximum.
C-1500 Extended Cab
Standard Box (2WD)*Axle Ratio Maximum Trailer Weight GCWR
4.3L V63.23
3.734,300 lbs (1 950 kg)
4,800 lbs (2 177 kg)9,500 lbs (4 309 kg)
10,000 lbs (4 536 kg)
4.8L V83.23
3.734,700 lbs (2 132 kg)
6,700 lbs (3 039 kg)10,000 lbs (4 536 kg)
12,000 lbs (5 443 kg)
5.3L V83.42
3.736,700 lbs (3 039 kg)
7,700 lbs (3 493 kg)12,000 lbs (5 443 kg)
13,000 lbs (5 897 kg)
6.0L V8 3.73 10,300 lbs (4 717 kg) 15,500 lbs (7 031 kg)
*Fifth-wheel or gooseneck kingpin weight 15 percent to 25 percent of trailer weight up to 1,500 lbs (680 kg)
maximum.
*Fifth-wheel or gooseneck trailer rating limited to 6,800 lbs (3 084 kg) except with 6000 V8 engine limited to
6,900 lbs (3 130 kg).
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