
Trailer Brakes
If your trailer weighs more than 1,500 lbs (680 kg) loaded,
then it needs its own brakes — and they must be
adequate. Be sure to read and follow the instructions for
the trailer brakes so you’ll be able to install, adjust and
maintain them properly.
Since your vehicle is equipped with StabiliTrak
®, your
trailer brakes cannot tap into the vehicle’s hydraulic brake
system.
Driving with a Trailer
{CAUTION:
If you have a rear-most window open and you
pull a trailer with your vehicle, carbon
monoxide (CO) could come into your vehicle.
You can not see or smell CO. It can cause
CAUTION: (Continued)
CAUTION: (Continued)
unconsciousness or death. SeeEngine
Exhaust on page 2-36. To maximize your safety
when towing a trailer:
Have your exhaust system inspected for
leaks and make necessary repairs before
starting on your trip.
Keep the rear-most windows closed.
If exhaust does come into your vehicle
through a window in the rear or another
opening, drive with your front, main
heating or cooling system on and with the
fan on any speed. This will bring fresh,
outside air into your vehicle. Do not use
the climate control setting for maximum air
because it only recirculates the air inside
your vehicle. SeeDual Climate Control
System on page 3-21orDual Automatic
Climate Control System on page 3-24.
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.
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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 connection, 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.
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.
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.
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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.
You can tow in DRIVE (D). You may want to shift the
transmission to THIRD (3) or a lower gear, under heavy
loads or hilly conditions.
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a lower
temperature than at normal 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 a
few minutes before turning the engine off. If you do get
the overheat warning, seeEngine Overheating on
page 5-30.
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. When parking uphill, turn your wheels
away from the curb. When parking downhill, turn
your wheels into the curb.
2. Have someone place chocks behind the trailer
wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4-57 

4. Reapply the regular brakes. Then apply your
parking brake, and then shift into PARK (P).
5. 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.
SeeFour-Wheel Drive on page 2-28.
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, and
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. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transmission  uid (don’t over ll),
engine oil, axle lubricant, belt(s), 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.
4-58 

Trailer Wiring HarnessYour vehicle may have a seven-wire trailer towing
harness. This harness may have a seven-pin universal
heavy-duty trailer connector (if equipped with the
trailering package) that is attached to a bracket on the
hitch platform or included with the four-pin trailer
towing harness. If your vehicle is not equipped with the
heavy-duty trailer connector, you may purchase one
from your dealer. The seven-wire harness contains the
following trailer circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Running Lamps
White: Ground
Light Green: Back-up Lamps
Dark Blue: Electric Brakes
Red: Battery Feed (The chassis wiring ring terminal
must be fastened to a stud on the underhood
electrical center before the trailer feed will become
active.)
If you need to tow a light-duty trailer with a standard
four-way round pin connector, an adapter connector is
available from your dealer.
4-59 

If you are charging a remote (non-vehicle) battery, turn
on the headlamps to boost the vehicle system voltage
and properly charge the battery.
Your vehicle is also equipped with wiring for an electric
trailer brake controller. These wires are located
inside the vehicle on the driver’s side under the
instrument panel. These wires should be connected to
an electric trailer brake controller by your dealer or
a quali ed service center.
Your vehicle may be equipped with a four-pin trailer
towing harness. This harness has a four-pin trailer
connector that contains the following trailer circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Running Lamps
White: GroundThis harness also contains the following trailer circuits
that are not connected to the four-pin trailer connector:
Light Green: Back-Up Lamps
Dark Blue: Electric Brakes
Red: Battery Feed
If your vehicle is a TrailBlazer SS, you were provided with
a trailer wiring harness extension, and instructions for
installing this extension, when your vehicle was delivered.
This extension will allow your vehicle’s trailer wiring
harness to be more easily accessible. There is a four-way
connector on the harness. A seven-way adapter plug is
also included in case your trailer requires it.
4-60