1993 GMC SIERRA trailer

Features & Contmls
Four- Wheel Drive
CAUTION I
It can be dangerous to get out of your vehicle if the shift lever -is not
fully in
P (Park) with the parking brake firmly set. Your vehicle can
roll. Don’t leave your vehicle when the engine is running unless you
have
to. If you’ve left the engine running, the vehicle can ‘move
suddenly. You or -others could be injured.
To be sure your vehicle
won’t move, even when you’re on fairly level ground, always
set your
parking brake and move the shift lever
to P (Park).
If you have four-wheel drive and your transfer case is in N (Neutral),
your vehicle
will be free to roll, even if your shift lever is in P’(Park).
So, be sure the transfer case is in a drive gear-not in N (Neutral).
Follow the proper steps
to be suce your vehicle won’t move. See
“Shifting Into
P (Park)” in the Index.
If you are parking on a hill, or if you’re pulling a trailer, also see
“Parking ‘on Hills’’ or “Towing a Trailer” in this section.
I
If your vehicle has four-wheel drive, you can send your engine’\
s driving power
to all four wheels for extra traction. To get the most satisfaction out of
four-wheel drive, you must be familiar with it’s operation. \
Read the part that
follows before using four-wheel drive. You should use
2H for most normal
driving conditions.
Rear-wheel antilock brakes
do not work when you shift into four-wheel drive.
Your regular brakes will still work. When you shift back into two-w\
heel drive,
your rear-wheel antilock brakes will take over again.
I NOTICE
Driving in the 4H or 4L positions for a long time on dry or wet pavement
could shorten the life
of your vehicle’s drivetrain.
2-36
ProCarManuals.com

.
You can only drive for a short time with the reading in either warning zone. If
you must drive, turn
off all unnecessary accessories, and have the vehicle
serviced as soon as possible.
Camper Wiring Harness
The optional 5-wire harness is stored in’ the front stake pocket on the driver’s
side of’ the bed. The harness has no connector, and should be wired by\
a
qualified electrical service person.
It must be routed out of your vehicle and
securely attached
so that it won’t be pulled or rubbed while you’re using it.
Store the -harness in its original place. Wrap the harness together and tie it
neatly
so it won3 be damaged.
The optional 7-wire harness
is stored under your vehicle along the rear frame
crossmember. The harness has a’
30 amp. in-line fused battery feed wire and
no connector, and should be wired by a qualified electrical se\
rvice person.
Securely attach
the harness to the trailer, then tape or strap it to your
vehicle’s frame rail. Be sure you leave it loose enough
so the wiring won’t
bind
or break when turning with the trailer, but not so loose that it drags on
the ground.
Store the harness in its original position. Wrap the harness together and tie it
neatly so it won’t be damaged. ,
2-9 1
ProCarManuals.com

Parking on Hills ........................................................................\
........................... 4-49
Winter Driving
........................................................................\
.............................. 4-52
Towing a Trailer
........................................................................\
........................... 4-55
Power Winches ........................................................................\
............................ 4-62
Power Take-Off
........................................................................\
............................ 4-62
4-2
ProCarManuals.com

AM480043
Run your engine only as long as you musk. This saves fuel. When you run
the engine, make it go a little faster than just idle. That is, push the
accelerator slightly. This uses less fuel for the heat that yo\
u get and
it keeps
the battery (or batteries) charged. You will need a well-charged battery (or
batteries) to restart the' vehicle, and possibly for signaling later on with your
headlights. Let the heater run for awhile.
If you 'have a diesel engine, you
may have to run it at a higher speed
to lget enough heat. Then, shut the
engine
off and close the window almost all the way to preserve the heat.
Start the engine again and repeat this only when you feel really
uncomfortable from the cold. But
do it as little as'possible. Preserve the fuel
as long as you can.
To help keep warm, you can get out of the vehicle and
do some fairly vigorous exercises every half hour or so until help comes.
If You're Stuck in Deep Snow
This manual explains how to get the vehicle out of deep snow without
damaging it. See "Rocking Your Vehicle" in the Index.
Towing a mailer
CAUTION I
If you don't use the correct equipment and drive properly, you ca\
n
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.
I
i'- ." "
4-55
ProCarManuals.com

z
Your Driving and the Road
NOTICF
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 section.
Every vehicle
is ready for some trailer. towing. If it was .built with trailering
options, as many are,
it’s ready for‘heavier trailers. But trailering is different
than just driving your vehicle by itself. Trailering means chan\
ges isn handling,
durability, and fuel .economy. Successful, safe trailering .takes\
correct
equipment, and
it has to be used properly.
That’s the reason for this section. 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.
If You Do Decide To Pull A Trailer
If you do, here are some important .points. .
0 There are many different laws 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 if your trailer will weigh 4,000 pounds
(1 800 kg) or less. You should always use a sway control if your trailer
will weigh more than 4,000 pounds (1800 kg). You can ask a hitch
dealer about sway controls.
Don’t tow a trailer at all during the first 500 miles (800 km) ‘your new
vehicle is driven. Your engine, axle,
or other parts could be damaged.
Then, during the first 500 miles (800 km) that you tow a trailer, don’t
drive over
50 mph (80 km/ti) and don’t make ,starts at full throttle. T\
hat
will help your engine and other parts of your vehicle wear in at the
heavier load$.
Three important considerations have to do with weight:
Weight
Weight of the Trailer
How heavy can a trailer safely be?
It should never be more than 13,500 Ibs. (6125.6 kg). But even \
that can be
too heavy. It depends on how you plan to use your rig. For example, speed,
altitude, ‘road grades, outside temperature, and how much your vehicle is
4-56
ProCarManuals.com

used to pull a trailer all are important. And, it can also depend on any
special equipment that you have on your vehicle. You can ask your dealer
for
our trailering information or advice, or you can write us at the address listed
in your Warranty and Owner Assistance Information Booklet.
In Canada, write to:
General Motors of Canada Limited
Customer Assistance Center
1908 Colonel Sam Drive
Oshawa, Ontario
L1H 8P7
Weight of the Trailer Tongue
The tongue load (A) of any trailer is an important weight t\
o measure because
it affects the total, gross weight
of your vehicle. The gross vehicle weight
(GVW) includes the curb weight
of the vehicle, any cargo you may carry in it,
and the people who will be riding in the vehicle. And if you will tow a trailer,
you must add the tongue load to the GVW because your vehicle will be
carrying that weight, too. See “Loading Your Vehicle” in the Index
for more
information about your vehicle’s maximum load capacity.
A
m
B
AN490002
If you’re using a “dead-weight” hitch, the trailer tongue (A) should weigh 10%
of the total loaded trailer weight (B). If you have a “weight-distributing” hitch,
the trailer tongue (A) should weigh
12% of the total loaded trailer weight (B).
After you’ve loaded your trailer, weigh the trailer and then\
the tongue,
separately,
to see if the weights are proper. If they aren’t, you may be able
to get them right simply by moving some items around in the \
trailer.
4-57
ProCarManuals.com

Your Driving and the Road
Total Weight on Your Vehicle’s Tires
Be sure your vehicle’s tires are inflated to the limit for cold tires. You’ll find
these numbers on the Certification label at the rear edge of the driver’s door
(or see “Tire Loading” in the Index). Then be sure you don’t go over the
GVW limit for your vehicle.
Hitches
It’s important to have the correct hitch equipment. Crosswinds, large trucks
going by, and rough roads are a few reasons why you’ll need the righ\
t hitch.
Here are some rules
to follow:
If your vehicle has a step bumper and you are going to use a ball-type
hitch, remove the pad and cut holes in
it to match the hitch and safety
chain holes in the bumper.
If you’ll be pulling a trailer that, when loaded, will weigh more than 4,000
pounds (1800 kg) be sure to use a properly mounted weight-distributing
hitch and sway control of the proper size. This equipment is very
important for proper vehicle loading and good handling when you\
’re
driving.
Safety Chains
You should always attach chains between your vehicle and your trail\
er. Cross
the safety chains under the tongue of the trailer
so that the tongue will not
drop
to the road if it becomes separated from the hitch. Instructions about
safety chains may be provided by the hitch manufacturer
or by the trailer
manufacturer. Follow the manufacturer’s recommendation for atta\
ching safety
chains. Always leave just enough slack
so you can turn with your rig. And,
never allow safety chains to drag .on the ground.
Trailer Brakes
If your trailer weighs more than 1,000 pounds (450 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.
Don’t tap into your vehicle’s brake system
if the trailer’s brake system will use
more than
0.02 cubic inch (0.3~~) of fluid from your vehicles master cylinder.
If it does, both braking systems won’t work well. You could even lose your
brakes.
Will the trailer brake parts take 3,000 psi (20 650 kPa) of pressure? If
not, the trailer brake system must not be used with your vehi\
cle.
If everything checks out this far, then make the brake fluid tap at the
port on the master cylinder that sends fluid
to the rear brakes. But don’t
use copper tubing for this.
If you do, it will bend and finally break off.
Use steel brake tubing.
4-58
ProCarManuals.com

Driving with a Trailer
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
so responsive as your vehicle is by itself.
Before you start, check the trailer hitch and platform, safety \
chains, electrical
connector, lights, 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 lights and any trailer brakes are still working.
Following Distance
Stay at least twice as far behind the vehicle ahead as you w\
ould 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 g\
o 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 left, just move your 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
When you’re turning with a trailer, make wider turns than normal. Do this so
your trailer wheels 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
When you tow a trailer, your vehicle has to have a different turn signal
flasher and extra wiring. The green arrows on your instrument \
panel will flash
whenever you signal a turn or lane change. Properly hooked up, the trailer
lights will also flash, telling other drivers you’re about t\
o turn, change lanes,
or stop.
When towing a trailer, the green arrows on your instrument pan\
el will flash for
turns even
if the bulbs on the trailer are burned out. Thus, you may think
4-59
ProCarManuals.com