1997 GMC SIERRA Towing

Turn Signals When Towing a Trailer
The 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 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 km/h) to reduce the
possibility of engine and transmission overheating. If you have an automatic transmission, you can tow
in
AUTOMATIC OVERDRIVE (a). You
may want to
shift the transmission to THIRD
(3) or, if necessary, a
lower gear selection if the transmission shifts too often
(e.g., 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).
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
Parkine
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.
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.
Check periodically to see that all hitch nuts and bolts
are tight.
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Section 5 Problems on the Road
Here you’ll find what to do about some problems that can occur on the road.
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5-3
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5-1 1
Hazard Warning Flashers
Other Warning Devices
Jump Starting
Towing Your Vehicle
Engine Overheating (Gasoline Engine) Cooling
System
-- Gasoline Engines
Engine Fan Noise
If a Tire
Goes Flat
Changing
a Flat Tire
If You’re Stuck: In Sand,
Mud, Ice or Snow
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5-2 1
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10. Try to start the vehicle with the dead battery.
If it won’t start after a few tries, it probably
needs service.
11. Remove the cables in reverse order to prevent
electrical shorting. Take care that they don’t touch
each other or any other metal.
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:
0 That your vehicle has rear-wheel drive, or that it has
the four-wheel-drive option.
0 The make, model and year of your vehicle.
0 Whether you can move the shift lever for the
0 If there was an accident, what was damaged.
transmission and transfer
case, if you have one.
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.
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I A CAUTION:
To help avoid injury to you or others:
0 Never let passengers ride in a vehicle that is
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.
0 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.
front and rear
of vehicle.
being
towed.
For cab chassis models, use J-hooks on
I [ CAUTION:
t
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.
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 4. Put an automatic transmission in PARK (P) or
manual transmission in FIRST
(1).
5. Put the transfer case in NEUTRAL (N).
6. When the vehicle is hooked up, release the
7. Maximum speed 55 mph (88 kmh), distance
If your vehicle is a two-wheel drive or a four-wheel
drive with an electric shift transfer case,
use the
following directions: parking brake.
unlimited.
1.
2.
3.
If your vehicle is four-wheel drive with a manual transfer case, use the following directions:
1. Turn the ignition key to the OFF position.
2. Engage the parking brake.
3. Clamp the steering wheel in a straight-ahead position
with a clamping device designed for towing service.
(Do not use the vehicle’s steering column lock for this.)
4.
5.
6.
7.
Turn the ignition key to the OFF position.
Engage the parking brake.
Clamp the steering wheel in a straight-ahead
position with
a clamping device designed for
towing service.
(Do not use the vehicle’s steering
column lock
for this.)
Put an automatic transmission
in NEUTRAL (N) or
manual transmission in FIRST (1).
Put the transfer case
in 2HIGH (2HI).
When
the vehicle is hooked up, release the
parking brake.
Maximum speed
35 mph (55 km/h), maximum
distance
50 miles (80 km).
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Rear Towing
I NOTICE:
If your vehicle is equipped with a manual or
electric shift transfer
case, a towing dolly must be
used under the front wheels or vehicldpowertrain
damage
will occur.
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.
Engine Overheating (Gasoline Engine)
You will find a coolant temperature gage on your
vehicle’s instrument panel.
If your vehicle has a diesel engine, see “Engine
Overheating” in the Diesel Engine Supplement.
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Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When
the clutch is engaged, the fan spi.ns faster to provide
more air
to cool the engine. In most everyday 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 and/or high outside temperatures, the fan 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 disengages.
You may also hear this
fan 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. Take 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 may 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 flat, the next part shows how to
use your
jacking equipment
to change a flat tire safely.
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