1993 GMC SIERRA ECU

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
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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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Pzloblenrs on the Road
Pull the retainer through the wheel center. Attach the ratchet,\
with the UP
side facing you, to the wheel wrench. Put the chisel end of the wheel wrench
into the hole in the rear bumper. Turn the ratchet until the tire is raised
against the underside
of the vehicle.
You will hear
two “clicks” when the tire is secure, but pull on the tire to
make sure.
Return the jack, ratchet, wheel wrench and jack extensions to their location
behind the passenger’s seat. Secure the items and replace th\
e jack cover
if
there is one.
Storing Tire ln Pickup Bed
K2534
1. Place the bolt through the bottom wheel nut hole. Be sure the valve
2. Place the nut on the bolt and turn it clockwise until the ti\
re is secure.
faces out.
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Service & Appearance Care
Windshield Wiper Blade Inserts
I -
r
PO232
To replace the windshield wiper blade insert, lift the wiper arm and rotate the
blade until it is facing away from the windshield. Unlatch the\
end of the insert
from the holding clips. Remove the insert and slide a new one\
in place.
Make sure the blade is secured in the clips.
Air Conditioning
Every now and then have your dealership check your air conditi\
oning system
to be sure it has not lost any cooling ability.
If you think the system is not
working properly, have your dealership check it out as soon as\
possible.
The air conditioning will not work when the temperature is bel\
ow 40°F
(4°C).
Fluid Leak Check
After the vehicle has been parked for a while, inspect the su\
rface under the
vehicle
for water, oil, fuel or other fluids. Water dripping from the air
conditioning system after it has been used is normal, If you notice fuel leaks
or fumes, the causes should be found and corrected at once.
Lubrication
Accelerator Control System
Your maintenance schedule will tell you how often the accelerator linkage
pivot points must be lubricated. See “Recommended Fluids and \
Lubricants” in
the Index for the proper lubricant to use.
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Loading Your Vehicle
The CertificationKire label is found on the rear edge of the driver’s door or in
the incomplete vehicle document in the cab. The label shows th\
e size of your
original tires and the inflation pressures needed
to obtain the gross weight
capacity of your vehicle. This is called the GVWR (Gross Vehicle Weight
Rating). The
GWVR includes the weight of the vehicle, all occupants, fuel and
cargo.
The CertificationKire label also tells you the maximum weights for the front
and rear axles, called Gross Axle Weight Rating (GAWR). To find out the
actual loads on .your front and rear axles, you need to go to a weigh station
and weigh your vehicle. Your dealer can help you with this. .Be sure to
spread out your load equally on both sides of the centerline+
.. , - :I. -I lrT1 I I -
Never exceed the GVWR for your vehicle, or the Gross, Axle Weight Rating-
(GAWR) for either the front or rear axle.
And,
if you do have a heavy load, you should spread it out.
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In the case of a sudden stop or collision, things carried in the bed of 7
injuring you and others. If you put things in the bed of your truck,
you should make sure they are properly secured.
r! your truck could shift forward and come into the passenger are\
a,
-
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Service & Appearance Care
A Do not load your vehicle any heavier than the GWR or the
- b maximum front and rear GAWRs. If you do, parts on your vehicle
can break, or it can change the way your vehicle handles. These
could cause you to lose control.
Also, overloading can shorten the
life
of your vehicle.
Using heavier suspension components to get added durability migh\
t not
change your weight ratings. Ask your dealer to help you load \
your vehicle the right way.
.,ur warranty does
nnt cover par nr componentg that fail becausl
overloading.
If you put things inside your vehicle-like suitcases, tools, packag\
es, or
anything else-they will go as fast as the vehicle goes. If you have to stop
or turn quickly, or if there is a crash, they’ll keep going.
* Things you put inside your vehicle can strike and injure peopl\
e in a
9 Put things in the cargo area of your vehicle. Try to spread the
9 Never stack heavier things, like suitcases, inside the vehicle so
d sudden stop or turn, or in a crash.
weight evenly.
that some
of them are above the tops of the seats.
When you
carry something inside the vehicle, secure it
whenever you can.
Don’t have a seat folded down unless you need to.
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Service & Appearance Care
Tire Chains
If your vehicle has dual wheels or LT265175R16 size tires, don’t use tire
chains; they can damage your vehicle.
__ you don’t have dual wheels or if you have a tire size other than
LT265/75R16, use tire chains only when you must. Use only
SAE
“S” type chains that are the proper size for your tires. Install \
them on the
tires of the rear axle. 3
Tighten the as tightly as possible with the ends securely fastened. Drive I
slowly and TOIIOW the chain manufacturer’s instructions. If you can hear the
chains contacting your vehicle, stop and retighten them.
If the contact
continues, slow down until
it stops. Driving too fast with chains on will ’
nage your vehicle.
1 CAUTION
Appearance Cam
I
Cleaning products can be hazardous. Some are toxic. Others can \
L burst into flame if you strike a match or get them on a hot part of
the vehicle. Some are dangerous
if you breathe their fumes in a
zlosed space. When you use anything in a container to clean your
vehicle, be sure
to follow the instructions. And always open your
doors or windows when you’re cleaning the inside.
I ter use these to clean your vehicle:
Gasoline
Benzene
Naphtha
Carbon Tetrachloride
Acetone
Paint Thinner
Turpentine
Lacquer Thinner
Nail Polish Remover
They can all be hazardous-some more than others-and they can
all damage your vehicle, too.
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