2006 GMC SIERRA 1500 Owners Manual

Towing a trailer requires a certain amount of experience.
Before setting out for the open road, you’ll want to get to
know your rig. Acquaint yourself with the feel of handling
and braking with the added weight of the trailer. And
always keep in mind that the vehicle you are driving is
now a good deal longer and not nearly as responsive as
your vehicle is by itself.
Before you start, check all trailer hitch parts and
attachments, safety chains, electrical connector, lamps,
tires and mirror adjustment. If the trailer has electric
brakes, start your vehicle and trailer moving and then
apply the trailer brake controller by hand to be sure the
brakes are working. This lets you check your electrical
connection at the same time.
During your trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer brakes
are still working.
While towing a trailer or when exposed to long periods
of sunshine, the oor of the truck bed may become very
warm. Avoid putting items in the truck bed that might be
affected by high ambient temperatures.Following Distance
Stay at least twice as far behind the vehicle ahead as you
would when driving your vehicle without a trailer. This can
help you avoid situations that require heavy braking and
sudden turns.
Passing
You’ll need more passing distance up ahead when
you’re towing a trailer. And, because you’re a good
deal longer, you’ll need to go much farther beyond
the passed vehicle before you can return to your lane.
Backing Up
Hold the bottom of the steering wheel with one hand.
Then, to move the trailer to the left, just move that hand
to the left. To move the trailer to the right, move your
hand to the right. Always back up slowly and, if possible,
have someone guide you.
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Making Turns
Notice:Making very sharp turns while trailering
could cause the trailer to come in contact with the
vehicle. Your vehicle could be damaged. Avoid
making very sharp turns while trailering.
When you’re turning with a trailer, make wider turns than
normal. Do this so your trailer won’t strike soft shoulders,
curbs, road signs, trees or other objects. Avoid jerky or
sudden maneuvers. Signal well in advance.
Turn Signals When Towing a Trailer
The arrows on your instrument panel will ash whenever
you signal a turn or lane change. Properly hooked up, the
trailer lamps will also ash, telling other drivers you’re
about to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument
panel will ash for turns even if the bulbs on the trailer are
burned out. Thus, you may think drivers behind you are
seeing your signal when they are not. It’s important to
check occasionally to be sure the trailer bulbs are still
working.
Driving On Grades
Reduce speed and shift to a lower gearbeforeyou start
down a long or steep downgrade. If you don’t shift down,
you might have to use your brakes so much that they
would get hot and no longer work well.If you have an automatic transmission, you can tow
in DRIVE (D). You may want to shift the transmission to
a lower gear selection if the transmission shifts too
often (e.g., under heavy loads and/or hilly conditions).
You may also want to activate the tow/haul mode if
the transmission shifts too often. SeeTow/Haul Mode
Light on page 3-50.
If you have a 5-speed manual transmission and you are
towing a trailer, it’s better not to use FIFTH (5) gear.
Just drive in FOURTH (4) gear (or, as you need to, a
lower gear).
If you have a 6-speed manual transmission and you are
towing a trailer, it’s better not to use SIXTH (6) gear.
Drive in FIFTH (5) gear (or, as you need to, a lower gear).
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant at or near sea level
will boil at a lower temperature than at higher altitudes.
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 the automatic transmission in PARK (P) for
at least ve minutes before turning the engine off. For
manual transmissions, let the engine run while parked,
preferably on level ground, with the transmission out
of gear and the parking brake applied, for at least ve
minutes before turning the engine off. If you do get the
overheat warning, seeEngine Overheating on page 5-37.
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Parking on Hills
{CAUTION:
You really should not park your vehicle, with
a trailer attached, on a hill. If something goes
wrong, your rig could start to move. People
can be injured, and both your vehicle and the
trailer can be damaged.
But if you ever have to park your rig on a hill, here’s
how to do it:
1. Apply your regular brakes, but don’t shift into
PARK (P) yet for an automatic transmission,
or into gear for a manual transmission.
2. Have someone place chocks under the trailer
wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4. Reapply the regular brakes. Then apply your
parking brake and shift into PARK (P) for an
automatic transmission, or REVERSE (R) for
a manual transmission.
5. If you have a four-wheel-drive vehicle, be sure the
transfer case is in a drive gear and not in NEUTRAL.
6. Release the regular brakes.
{CAUTION:
It can be dangerous to get out of your vehicle if
the shift lever is not fully in PARK (P) with the
parking brake rmly set. Your vehicle can roll.
If you have left the engine running, the vehicle
can move suddenly. You or others could be
injured. To be sure your vehicle will not move,
even when you are on fairly level ground, use
the steps that follow.
Always put the shift lever fully in PARK (P) with
the parking brake rmly set.
If the transfer case on four-wheel-drive vehicles
is in NEUTRAL, your vehicle will be free to roll,
even if your shift lever is in PARK (P). So, be
sure the transfer case is in a drive gear — not
in NEUTRAL.
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When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
Start your engine
Shift into a gear
Release the parking brake
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the
chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re
pulling a trailer. SeeScheduled Maintenance (Gasoline
Engine) on page 6-4for more information. Things that
are especially important in trailer operation are automatic
transmission uid (don’t overll), engine oil, axle
lubricant, belt, cooling system and brake system. Each of
these is covered in this manual, and the Index will help
you nd them quickly. If you’re trailering, it’s a good idea
to review these sections before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Trailer Wiring Harness
Your vehicle is equipped with one of the following wiring
harnesses for towing a trailer or hauling a slide-in
camper.
Basic Trailer Wiring
All regular, extended cab and crew cab pickups have an
eight-wire trailer towing harness.
For vehicles not equipped with heavy duty trailering, the
harness is clipped to the vehicle’s frame behind the spare
tire mount. The harness requires the installation of a
trailer connector, which is available through your dealer.
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If your trailer is equipped with electric brakes, you can
get a jumper harness (electric trailer brake control)
with a trailer battery feed fuse from your dealer.
If you need to tow a light-duty trailer with a standard
four-way round pin connector, you can also get an
adapter form your dealer.
Heavy-DutyTrailer Wiring Harness
Package
For vehicles equipped with heavy duty trailering, the
harness is connected to the trailer plug mounted to the
hitch platform.The eight-wire harness contains the following trailer
circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Taillamps
White: Ground
Light Green: Back-up Lamps
Light Blue: CHMSL*
Red: Battery Feed**
Dark Blue: Trailer Brake
* The Center High-Mounted Stoplamp (CHMSL) wire
is tied next to the trailer wiring harness for use with
a trailer, slide-in camper or cap.
**If you are charging a remote (non-vehicle) battery,
turn on the headlamps to boost the vehicle system
voltage and properly charge the battery.
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Camper/Fifth-Wheel Trailer Wiring Package
The eight-wire camper harness is located under the front
edge of the pickup box on the driver’s side of the vehicle,
attached to the frame bracket. A connector will have to be
added to the wiring harness which connects to the
camper.
The eight-wire harness contains the following
camper/trailer circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Taillamps
White: Ground
Light Green: Back-up Lamps
Light Blue: Center High-Mounted
Stoplamp (CHMSL)
Red: Battery Feed
Dark Blue: Trailer BrakeIf your vehicle is equipped with the “Heavy-Duty
Trailering” option, please refer to “Heavy-Duty Trailer
Wiring Package” earlier in this section.
When the camper-wiring harness is ordered without the
heavy-duty trailering package, an eight-wire harness with
a seven-pin connector and separate CHMSL connector
are located at the rear of the vehicle and are tied to the
vehicle’s frame.
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Electric Brake Control Jumper
{CAUTION:
Be sure to use only the correct trailer brake
harness, the one intended for use on your
vehicle. If you use some other trailer brake
harness, even if it seems to t, your trailer
brakes may not work at all. You could have a
crash in which you or others could be injured.
Use only the trailer brake harness intended for
your vehicle. If it is no longer available to you,
be sure to get a proper replacement from your
dealer.This harness is included with your vehicle as part of the
heavy-duty trailer wiring package.
This harness is for an electric brake controller and
includes a trailer battery feed fuse. It should be installed
by your dealer or a qualied service center.
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Auxiliary Battery
The auxiliary battery provision can be used to supply
electrical power to additional equipment that you
may choose to add, such as a slide-in camper.
If your vehicle has this
provision, this relay will be
located on the passenger’s
side of the vehicle, next
to the auxiliary battery.
When using this provision, connection should only be
made to the upper stud (A) of the relay. Do not make
connections to the lower stud (B) of the relay.
The auxiliary battery circuit is protected by a megafuse
located behind the auxiliary battery.
Be sure to follow the proper installation instructions that
are included with any electrical equipment that you install.Notice:Leaving electrical equipment on for
extended periods will drain the battery. Always turn
off electrical equipment when not in use and do not
use equipment that exceeds the maximum amperage
rating for the auxiliary battery provision.
Power Winches
If you wish to use a power winch on your vehicle, only
use it when your vehicle is stationary or anchored.
Trailer Recommendations
You must subtract your hitch loads from the CWR for your
vehicle. Weigh your vehicle with the trailer attached, so
that you won’t go over the GVWR or GAWR. If you are
using a weight-distributing hitch, weigh the vehicle
without the spring bars in place.
You’ll get the best performance if you spread out the
weight of your load the right way, and if you choose
the correct hitch and trailer brakes.
For more information, seeTowing a Trailer on
page 4-67.
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