1995 GMC SIERRA Owners Manual

Most vehicles are ready for some trailer towing. If yours 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 changes
in 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.
If You Do Decide To Pull A Trailer
If you do, here are some important points.
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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 if your trailer will weigh 4,000 pounds
(I 800 kg) or less. You should always use a sway control if your trailer
will weigh more than
4,000 pounds (1 800 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 kdh) and don’t make starts at full throttle. This
helps your engine and other parts of your vehicle wear
in at the heavier
loads.
If you have an automatic transmission, you should use DRIVE (3) (or,
as you need to, a lower gear) when towing a trailer. Operating your
vehicle in DRIVE
(3) when towing a trailer will minimize heat
build-up and extend the life
of your transmission. If you have a 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).
Three important considerations have
to do with weight:
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. And, it can
also depend on any special equipment
that you have on your vehicle.
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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
Ll H 8P7
Weight of the Trailer Tongue
The tongue load (A) of any trailer is an important weight to measure
because
it affects the total or 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 B
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.
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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, includins the weight of the trailer tongue.
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 right hitch.
Here are some rules to follow:
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If you use a step bumper hitch, and your trailer tongue has a V-shaped
foot. your bumper could be damaged
in sharp turns. Check the distance
from the front edge
of the foot to the middle of the hitch ball socket. If
the distance is less than 12 inches, take the foot off the trailer tongue.
If you‘ll be pulling a trailer that, when loaded,
will weigh more than
4,000 pounds
( 1 8 14 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 trailer.
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
attaching safety chains and do not attach them to the bumper. 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.
Your trailer brake system can tap into your vehicle’s hydraulic brake system,
but consider the following:
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 vehicle’s
master cylinder.
Tf it does, both braking systems won’t work well. You
could even lose your brakes.
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Will the trailer brake parts take 3,000 psi (20 650 Wa) of Ijressure? If
not, the trailer brake system must not be used with your vehicle.
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 as responsive as your vehicle is by itself.
Before you start, check the trailer hitch and platform (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.
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.
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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
I NOTICE:
Making very sharp turns while trailering could cause the traile\
r 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
When you tow a trailer, your vehicle has to have extra wiring (included in
the optional trailering package). The green arrows
on your instrument panel
will flash whenever
you signal a turn or lane change. Properly hooked up,
the trailer lamps will also flash, telling other drivers you’re about to turn,
change lanes or stop.
When towing a trailer, the green arrows on your instrument panel will flash
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 gear before you 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.
On
a long uphill grade, shift down and reduce your speed to around 45 mph
(70 kmh) to reduce the possibility of engine and transmission overheating.
If you have an automatic transmission
you should use DRIVE (3) (or, as
you need to, a lower gear) when towing a trailer. Operating your vehicle in
DRIVE (3) when towing a trailer will minimize heat build-up and extend
the life
of your transmission.
If you have a 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).
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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 (Pj (or the manual transmission
out
of gear and the parking brake applied) for a few minutes before turning
the engine off.
If you do get the overheat warning, see “Engine
Overheating”
in the Index.
Parking on Hills
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.
2.
3.
4.
5.
6.
Apply your regular brakes, but don’t shift into PARK (P) yet, or in gear
for a manual transmission.
Have someone place chocks under the trailer wheels.
When the wheel chocks are
in place, release the regular brakes until the
chocks absorb the load.
Re-apply the regular brakes. Then apply your parking brake, and then
shift
to PARK (P), or REVERSE (Rj for a manual transmission.
If you have
a four-wheel-drive vehicle, be sure the transfer case is in a
drive gear-not in NEUTRAL
(N).
Release the regular brakes.
A 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 firmly set. Your
vehicle can rofl.
If you have Ieft 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, use the
steps that follow.
If you have four-wheel drive and your transfer case is in
NEUTRAL (N), 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 (N).
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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; 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 fluid (don’t
overfill), engine oil, axle lubricant, belt, cooling system, and brake
adjustment. Each of these is covered
in this manual, and the Index will help
you find 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 Lighting Systems Wiring
See “Trailer Wiring Harness” in the Index.
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