1993 GMC SIERRA towing

Problenrs on the Road
Towing Your Vehicle
Try to have a GM dealer or a professional towing service tow your vehicle.
They can provide the right equipment and know how to tow it without dam-
age.
If your vehicle has been changed since it was factory-new, by adding things
like fog lamps, aero skirting, or special tires and wheels, th\
ese things could
be damaged during towing.
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 four-wheel drive
option.
The make, model, and year of your vehicle.
Whether you can move the shift lever for the transmission and \
transfer case,
if you have one.
If there was an accident, what was damaged.
I A To help avoid injury to you or others:
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.
When your vehicle is being towed, have the ignition key
off. 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 Neu-
tral and the parking brake released.
If you have a two-wheel drive vehicle, don’t have your vehicle \
towed on the
rear wheels, unless you must. If the vehicle must be towed on\
the rear
wheels, don’t go more than
35 mph (56 km/h) or farther than 50 miles (80
krn) or your transmission will be damaged. If these limits must be exceeded,
then the rear drive wheels have to be supported on a dolly.
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Engine Fan Noise
This vehicle has a clutched engine cooling fan. When the clutch is engaged,
the fan spins faster to provide more air to
cool the engine. In most every day
driving conditions the clutch is not engaged. This improves fue\
l economy and
reduces fan noise. Under heavy vehicle loading, trailer towing andlor high
outside temperatures, the fan speed increases when the clutch e\
ngages.
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 disengages.
If a Tire Goes Fiat
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, 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 your tire goes flat, the next part shows how to use your jacking equipment
to change a flat tire safely.
Changing a Flat Tire
If a tire goes flat, avoid further tire and wheel damage by driv\
ing slowly to a
level place. Turn on your hazard warning flashers.
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Underbody Carrier
I CAUTION
To help avoid personal injury and property damage, never remove or
restow a tire fromho a stowage position under the vehicle while the
vehicle is supported by a jack. Always tighten the tire fully against
the underside of the vehicle when restowing.
To Remove the Spare Tire
a
K2535
The ratchet has an UP marking and a DOWN marking.
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If You’re Stuck: In Sand,
Mud,
Ice or Snow
What you don’t want to do when your vehicle is stuck is to spin your
wheels. The method known as “rocking” can help you get o\
ut when you’re
stuck, but you must use caution.
CAUTION - --
I * If you let your tires spin at high speed, they can explode and you or
,A others could be injured. And, the transmission or other parts of the
vehicle can overheat. That could cause an engine compartment fire
or other damage. When you’re stuck, spin the wheels as little as
possible. Don’t spin the wheels above
35 mph (55 krnlh) as shown
I on the speedometer.
;pinning your wheels can destroy parts of your vehicle as well as the
res.
If you spin the wheels too fast while shifting your transmission back
.nd forth, you can destroy your transmission.
NOTICE 1
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
R and a forward gear
(or with a manual transmission, between First or Second gear and Reverse),
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 may 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.
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Service & Appearance Care
Trailer Recommendations
You must subtract your hitch loads from the CWR for your vehicle. Weigh
your vehicle with your trailer attached,
so that you won’t go over the GVWR
or the GAWR.
You’ll get the best performance
if you spread out the weight of your load the
right way, and
if you choose the correct hitch and trailer brakes.
For more information, see “Trailer Towing” in the Index.
If you want more information on curb weights, cargo weights, cargo wei\
ght
rating and the correct center of gravity zone for your vehicle, your dealer can
help you. Just ask for a copy of “Consumer Information, Truck-Cam\
per
Loading.”
Pickup Conversion lo. Chassis Cab
General Motors is aware that some vehicle owners may consider having the
pickup box removed and a commercial
or recreational body installed. Before
you do
so, first contact the GM Zone Office for your area for information on
such conversions. (See the “Warranty and Owner Assistance”\
booklet for
Zone Office.) Owners should be aware that, as manufactured, th\
ere are
differences between a chassis cab and a pickup with the box r\
emoved which may affect vehicle safety. The components necessary to adapt the pickup to
permit its safe use with a specialized body should be installed by a bod\
y
builder in accordance with the information available from the Z\
one Office.
Tires
We don’t make tires. Your new vehicle comes with high quali\
ty tires made by
a leading tire manufacturer. These tires are warranted by the \
tire
manufacturers and their warranties are delivered with every new \
vehicle.
If
your spare tire is a different brand than your road tires, you will have a tire
warranty folder from each of these manufacturers.
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23. EXHAUST PRESSURE REGULATOR VALVE INSPECTION* -Check that
the valve works properly. Correct any binding. Inspect hoses fo\
r cracks, chafing or decay. Replace parts as needed.
24.
TIRE AND WHEEL ROTATION AND INSPECTION -For proper wear
and maximum tire life, rotate tires at the first
6,000 miles (1 0 000
kilometers) for Schedule I (t) or 7,500 miles (12 500 kilometers) for
Schedule
II (.) and then every 15,000 miles (25 000 kilometers)
thereafter. Follow the instructions and patterns shown in Section 6.
Check tires for uneven wear or damage.
If irregular or premature wear is
apparent, check wheel alignment. Also, check for damaged wheels.\
See
“Tires” in the Index for more information.
For dual wheels, whenever the vehicle, wheels, or fasteners are new,
have the wheel fastener torque set at the first 100,
1,000 and 6,000
miles (160, 1600 and 10
000 km).
For 3500 H.D. Models, block the tires opposite those being removed to
keep the vehicle from rolling.
25.
DRIVE AXLE SERVICE -Check readfront axle fluid level and add as
needed. Check constant velocity joints and axle seals for leaki\
ng.
Locking differential-Drain fluid at first oil change and refill. Check
fluid level and add as needed at subsequent oil changes.
In dusty
areas, or trailer towing applications drain fluid at every 15,0\
00 miles
(24 135 kilometers) and refill$
every oil change. In dusty areas, or trailer towing applications, drain
fluid every 15,000 miles
(24 135 kilometers) and refi1l.t
More frequent lubrication may be required on heavy-duty or off-road
use.
Standard differential -Check fluid level and add as needed at
26.
BRAKE SYSTEM INSPECTION -When the engine oil is changed,
inspect the lines and hoses for proper hookup, binding, leaks, \
cracks,
chafing, etc. Check the parking brake adjustment, and the fluid level in
the master cylinder.
A low fluid level can indicate worn disc brake pads
which may need to be sewiced.t
*An Emission Control Service
tA fluid
loss in these systems may indicate a problem. Have them
inspected and repaired at once.
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To contact NHTSA, you may either call the Auto Safety Hotline tol\
l-free at
1-800-424-9393
(or 366-0123 in the Washington, D.C. area) or write to:
NHTSA, U.S. Department of Transportation, Washington, D.C. 20590. You can
also obtain other information about motor vehicle safety from t\
he Hotline.
Reporting Safety Defects to the
Canadian Government
If you live in Canada, and you believe that your vehicle has a safety defect,\

you should immediately notify Transport Canada, in addition to notifying
General Motors
of Canada Limited. You may write to: Transport Canada at
Box 8880, Ottawa, Ontario K1G 3J2.
Reporting Safety Defects to General
Motors
In addition to notifying NHTSA (or Transport Canada) in a situation like this.
we certainly hope you'll notify us. Please call us at 1-800-GMC-TR\
UCK
(1-800-462-8782),
or write: GMC Truck, Consumer Relations, 31 E. Judson
Street 1607-07, Pontiac, Michigan 48342-2230. In Canada, please \
call us at 1-800-263-3777 (English)
or 1-800-263-7854 (French). Or, write: General
Motors of Canada Limited, Customer Assistance Center, 1908 Colonel Sam
Drive, Oshawa, Ontario L1H 8P7.
Roadside Assistance
GMC Truck's Roadside Assistance provides stranded owners with
over-the-phone roadside repairs
or towing service for disabled vehicles. This
service combines the efforts of technically trained telephone representatives
with a network of GMC Truck's dealer services.
Just dial GMC Truck Roadside Assistance at 1-800-GMC-TRUCK
(1 -800-462-8782)
to reach a qualified representative who can assist you in
repair
or arrange a tow. Other recommended services can also be arranged
for situations such as retrieving locked-in keys, changing a tire, or delivering
gasoline, at a charge
to the owner. We also provide dealer information at no
charge such as location of the nearest GMC Truck dealer and their hours
of
operation.
Roadside Assistance is available 24 hours a day, seven days a \
week, 365
days a year, including weekends and holidays. Should you have \
any
questions about Roadside assistance, call the GMC Truck Roadside
Assistance Center
or Contact your dealer.
In Canada, call 1-800-268-6800 for details on Roadside Assistance.
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Towing
A Trailer ...................................... 4-55
Maintenance
.............................. 4-61
Recommendations
................... 6-72
Turn Signals
.............................. 4-59
Traffic Lights
................................... 4-8
Trailer Brakes
.............................. 4-58
Trailering Package
........................ 6-69
Transfer Case
..................... 2.37. 6-39
Transmission
Automatic
.................................. 2-2 1
Five-Speed Manual ........ 2.24. 2-25
Fluid
................................ 6.33. 6-36
Fluid. To Add
................. 6.35. 6-37
Four-wheel
Manual Shift Speeds
............... 2-28
Shift Light
.................................. 2-27
Torque Lock (Automatic Transmission)
............. 2.30. 4-51
Trip Odometer
............................... 2-77
Turn SignaVMuItifunction Lever
.. 2.42
Indicator
...................... 2.43. 2-86
Following Distance
................... 4.59
Wiring Harness
.............. 2.91, 6-64
(See “Four-Wheel Drive”)
Turn SignaVLane Change
V
Damage Warnings ...................... 0-3
Vehicle Identification Number
............... 6-93
Loading
...................................... 4-26
Symbols
...................................... 0-4
Ventilation System
......................... 3-2
Air Vents
...................................... 3-3
Voltmeter
....................................... 2-90
Tips
............................................... 3.2
W
Warning
and Indicator Lights .... 2-78
Devices. Other
............................ 5-3
Wheels Alignment and Tire
Balance
.................................... 6-82
Aluminum
.................................. 6-89
Hub Caps and
Wheel Nut Caps
..................... 5-24
Nut Torque ..................... 6.51. 6-95
Replacement
............................. 6-83
Used Replacement
................... 6-83
Windows
........................................ 2-39
Sliding Rear
.............................. 2-40
Swing-Out
.................................. 2-40
Windshield Washer
...................... 2-46
Washer Fluid
............................ 6-48
Winter Driving
.............................. 4-52
Wipers, Windshield
........ 2-45, 6-64, 6-100
Blade Chatter
............................ 6-88
Blade Inserts
............................ 6-52
Cleaning Blades
........................ 6-88
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