towing GMC SIERRA 1996 User Guide

0 If you have an automatic transmission, you can tow
in OVERDRIVE
(@). You may want to shift the
transmission to THIRD (3) or, if necessary, a lower
gear selection if the transmission shifts too often
(eg, under heavy loads and/or hilly conditions). 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:
the weight
of the trailer,
the weight
of the trailer tongue
and the weight
on your vehicle’s tires.
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. Use
one
of the following charts to determine how much
your vehicle can weigh, based upon your vehicle model
and options.
Maximum trailer weight is calculated assuming the
driver and
one passenger are 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.
Above
the 2,000 lbs. (908 kg) trailer rating, the engine
oil cooler is required
on C/K- 1500 models with gas
engines and
C/K-2500 models with gas engines and
3.73 (or lower) axle ratio.
Above
the 4,000 lbs. (1 800 kg) trailer rating,
heavy-duty or gas shock absorbers are required
on
C- 1500 models, and heavy-duty shock absorbers
or
the off-road chassis package are required on
K-1500 models.
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Y
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.
If your trarler weighs more than
1,000 lbs. (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
the vehicle’s
hydraulic brake system
only if:
The trailer parts can withstand 3,000 psi
(20 650 kPa) of pressure.
0 The trailer’s brake system will use less than
0.02 cubic inch (0.3 cc) of fluid from your vehicle’s
master cylinder. Otherwise, both braking systems
won’t work well. You could even lose your brakes. If
everything checks out this far, make the brake tap
at the port
on the master cylinder that sends the 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.
rrailer
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.
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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 slowlv 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.
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Turn Signals When Towing a Trailer
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 be~m 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 km/h) to reduce the
possibility
of engine and transmission overheating.
If you have an automatic transmission, you should use
THIRD
(3) (or, as you need to, a lower gear) when
towing a trailer. Operating your vehicle in THIRD
(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).
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) (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.
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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:
0 Start your engine;
Shift into a gear; and
0 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 Wiring Harness
A seven-wire harness is stored under the rear end of
your vehicle. between the frame rails. An electrical
connector
will need to be installed at the trailer end of
the harness, by a qualified electrical technician. For
additional trailer wiring and towing information please
consult your
GM dealer. 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. If you
tow a trailer, your Center High-Mounted Stoplamp
(CHMSL) may not be properly visible from behind.
You should select a trailer with
a CHMSL on it or, if
one is not available, have one installed. See your GM
dealer about how to connect your vehicle’s wiring to
a trailer CHMSL.
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12. Remove the cables in reverse order to prevent
electrical shorting. Take care that they don’t touch
each other or any other metal.
I
A. Heavy Metal Engine Part
B. Good Battery
C. Dead Battery
Towing Your Vehicle
Try to have your GM dealer or a professional towing
service tow your vehicle. See “Roadside Assistance”
in the Index.
If your vehicle has been changed since it was
factory-new, by adding such things as fog lamps,
aero skirting, or special tires and wheels, these’
instructions may not be correct.
Before you do anything, turn on the hazard
warning flashers.
When you call, tell the towing service:
That your vehicle .has rear-wheel drive, or that it has
The make, model and year of your vehicle.
Whether you can move the shift lever for the
If there was an accident, what was damaged.
When the towing service arrives, let the tow operator
know that this manual contains detailed towing
instructions and illustrations. The operator may want to
see them.
the four-wheel-drive
option.
transmission
and transfer case, if you have one.
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/A CAUTION:
To help avoid injury to you or others:
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Never let passengers ride in a vehicle that is
being towed.
Never tow faster than safe
or posted speeds.
Never tow with damaged parts not
fully secured.
Never get under your vehicle after it has
been lifted by the tow truck.
Always use separate safety chains on each
side when towing a vehicle.
For pickups (except cab chassis models),
use T-hooks on front of vehicle, J-hooks
on rear.
For cab chassis models, use J-hooks on
front and rear of vehicle.
I A CAUTION:
A vehicle can fall from a car carrier if it isn’t
adequately secured. This can cause
a collision,
serious personal injury and vehicle damage. The
vehicle should be tightly secured with chains or
steel cables before it is transported.
Don’t use substitutes (ropes, leather straps,
canvas webbing, etc.) that can be cut by sharp
edges underneath the towed vehicle.
When your vehicle
is being towed, have the ignition
key in the OFF position. The steering wheel should be
clamped in a straight-ahead position,
with a clamping
device designed
for towing service. Do not use the
vehicle’s steering column lock for this. The transmission
and transfer case,
if you have one, should be in
NEUTRAL (N) and the parking brake released.
Don’t have your vehicle towed
on the drive wheels
unless
you must. If the vehicle must be towed on the
drive wheels, be sure to follow the speed and distance
restrictions later
in this section or your transmission will
be damaged.
If these limitations must be exceeded, then
the drive wheels have to be supported on
a dolly.
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Front Towing
Tow Limits -- 35 mph (56 kdh), 50 miles (SO km)
If these limits must be exceeded, then the rear wheels
have
to be supported on n dolly.
Rear Towing
NOTICE:
Towing pickup models from the rear while loaded
with heavy cargo may cause the frame side rails
to flex sufficiently to allow the pickup box to contact the cab and
could cause damage to the
cab and/or box.
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Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When the
clutch
is engaged, the fan spins fdster to provide more air
to cool the engine.
In most every day driving conditions,
the fan
is spinning slower and the clutch is not fully
engaged. This improves fuel economy and reduces fan
noise. Under heavy vehicle loading, trailer towing andor
high outside temperatures, the
fm speed increases as the
clutch more fully engages.
So you may hear an increase
in fan noise. This is normal and should not be mistaken
as the transmission slipping or making extra shifts.
It is
merely the cooling system functioning properly. The fan
will slow down when additional cooling is not required
and the clutch partially disengages.
You may also hear this
fm noise when you start
the engine.
It will go away as the fan clutch
partially disengages.
If a Tire Goes Flat
It’s unusual for a tire to “blow out” while you’re driving,
especially
if you maintain your tires properly. If air goes
out
of a tire, it’s much more likely to leak out slowly.
But if you should ever have a “blowout,” here are a few
tips about what
to expect and what to do:
If a front tire fails, the flat tire will create a. drag that
pulls the vehicle toward that side. Fake your foot off the
accelerator pedal and grip the steering wheel firmly.
Steer to maintain
lane position, and then gently brake to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like
a skid and
ITMY require the same correction you’d use in
a skid. In any rear blowout, remove your foot from the
accelerator pedal. Get the vehicle under control by
steering the way you want the vehicle to
go. It may be
very bumpy and
noisy, but you can still steer. Gently
brake to a stop
-- well off the road if possible.
If a tire goes tlat, the next part shows how to use your
jacking equipment to change
a flat tire safely.
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Rocking your vehicle to get it out:
First. turn your steering wheel left and right. That will
clear the area around your front wheels. Then shift back
and forth between REVERSE
(R) and a forward gear (or
with a manual transmission, between FIRST (1) or
SECOND (2) and REVERSE(R)), spinning the wheels
as little as possible. Release the accelerator pedal while
you
shift. and press lightly on the accelerator pedal
when the transmission is
in gear. If that doesn't get you
out after a few tries. you nlay need to be towed out. Or,
you
can use your recovery hooks if your vehicle has
them.
If you do need.to be towed out, see "Towing Your
Vehicle" in the Index.
Using the Recovery Hooks
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