1993 GMC SIERRA Towing on the road

Featums & Contmls
R (Reverse)
Use this gear to back up.
Shifting
to R (Reverse) while your vehicle is moving forward could damage
your transmission. Shift
to R (Reverse) only after your vehicle is stopped. I
b
1
damaging your transmission, see “If Yo$re Stuck: In Sand, Mud, Ice or
Snow” in the Index.
N (Neutral)
In this position, your engine doesn’t connect with the wheels.
To restart when
you’re already moving, use
N (Neutral) only. Also, use N (Neutral) when your
vehicle is being towed.
CAUTION I
Shifting out of P (Park) or N (Neutral) while your engine is “racing”
(running at high speed) is dangerous. Unless your foot is fi\
rmly on
the brake pedal, your vehicle could move very rapidly. You cou\
ld lose
control and hit people
or objects. Don’t shift out of P (Park) or N
wI ! your enaine is racing.
I
NOTICE
I
1
Damage to your transmission caused by shifting out of P (Park) or N
(Neutral) with the engine racing isn’t covered by your war\
ranty.
OD (Automatic Overdrive)
This position is
for normal driving. If you need more power for passing, and
you’re:
- Going less than about 35 mph (56 km/h), push your accelerator
- Going about 35 mph (56 kmlh) or more, push the accelerator all the
pedal about halfway down
way down
You’ll shift down
to the next gear and have more power.
OD should not be used when towing a trailer, carrying a heavy load, driving
on steep hills,
or for off-road driving. Select D (third gear) when operating the
vehicle under any of these conditions.
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D (Third Gear)
This is like
OD, but you never go into Overdrive. You should use D when
towing a trailer, carrying a heavy load, driving on steep hills, or for off-road
driving.
2 (Second Gear)
This position gives you more power but lower fuel economy. You can use
2
on hills. It can help control your speed as you go down steep mountain
roads, but then you would also want to use your brakes
off and on.
If you manually select 2, the transmission will drive in second gear. You may
use this feature for reducing torque to the rear wheels when you are trying
to
start your vehicle from a stop on slippery road surfaces.
1 (First Gear)
This position gives you even more power (but lower fuel econo\
my) than
2.
You can use it on very steep hills, or in deep snow or mud. If the selector
lever
is put in 1, the transmission won’t shift into first gear until the vehic\
le is
going slowly enough.
NWTIGE
If your rear wheels can’t rotate, don’t try to drive. This might happen if
you were stuck in very deep sand or mud or were up against a. solid
object. You could damage your transmission.
AWZ , <,*,~l,<.,. ...
Also, if you stop when going uphill, don’t hold your vehic there with only the
accelerator pedal.
This could overheat and damage ,the transmission. Use your
brakes or shii into P (Park) to hdd your vehicle in position on a hill.
.,$*’,,&:&> ._,, , . ~ ~ ,>&:a
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Features & Controls
that the pedal is harder to push. Or, the pedal may go closer to the floor.\
It
may take longer to stop. If the light is still on, have the vehicle towed for
service. (See “Towing Your Vehicle” in the Index.)
CAUTION
* Your brake system may not be working properly if the brake warning
light is on. Driving with the brake warning light on can lead\
to an
accident.
If the light is still on after you’ve pulled off the road and
stopped carefully, have
+hq vehicle towed for service.
“WATER IN FUEL” Light
WATER
IN
FUEL I
-l PB010
This light will come on to warn you if there is too much water in the diesel
fuel system. For more information on how this light works, see\
“Diesel Fuel
Requirements and Fuel System” in the Index.
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z
Your Driving and the Road
NOTICF
Pulling a trailer improperly can damage your vehicle and result in costly
repairs
not covered by your warranty. To pull a trailer correctly, follow the
advice in this section.
Every vehicle
is ready for some trailer. towing. If it 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 chan\
ges isn handling,
durability, and fuel .economy. Successful, safe trailering .takes\
correct
equipment, and
it has to be used properly.
That’s the reason for this section. 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. .
0 There are many different laws 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
(1 800 kg) or less. You should always use a sway control if your trailer
will weigh more than 4,000 pounds (1800 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 km/ti) and don’t make ,starts at full throttle. T\
hat
will help your engine and other parts of your vehicle wear in at the
heavier load$.
Three important considerations have to do with weight:
Weight
Weight of the Trailer
How heavy can a trailer safely be?
It should never be more than 13,500 Ibs. (6125.6 kg). But even \
that can be
too heavy. It depends on how you plan to use your rig. For example, speed,
altitude, ‘road grades, outside temperature, and how much your vehicle is
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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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Your Driving and the Road
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 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
45 mph (70
kmlh) or less to reduce the possibility of engine and transmission overheating.
IT you have an automatic transmission, you should use D (or, as you need to,
a lower gear) when towing a trailer. Operating your vehicle i\
n
D when towing
a trailer will minimize heat buildup and extend the life of your transmission.
Or, if you have a manual transmission with fifth gear and you are towing a
trailer, it’s better not to use fifth gear. Just drive in fourth gear
(or, as you
need to, a lower gear).
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. Apply your regular brakes, but don’t shift into P (Park) yet, or into gear
2. Have someone place chocks under the trailer wheels.
for a manual transmission.
3. When the wheel chocks are
in place, release the regular brakes until the
chocks absorb the load.
4. Reapply the regular brakes. Then apply your parking brake, and \
then
5. If you have a four-wheel-drive vehicle, be sure the transfer case is in a
6. Release the regular brakes.
shift
to
P (Park), or R (Reverse) for a manual transmission.
drive gear-not in
N (Neutral).
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Pmb/ems on the Road
1 Section
Here you’ll find what to do about some problems that can occur on the road .
Hazard Warning Flasher ........................................................................\
............... 5-2
Other Warning Devices ........................................................................\
................. 5-3
Jump Starting ........................................................................\
................................ 5-3
Towing Your Vehicle ........................................................................\
...................... 5-8
Engine Overheating ........................................................................\
....................... 5-9
If
If
a Tire Goes Flat ........................................................................\
...................... 5-17
Changing a Flat Tire
........................................................................\
............... 5-17
Jack Storage
........................................................................\
............................ 5-19
Spare Tire
........................................................................\
................................ 5-20
You’re Stuck: In Sand. Mud. Ice or Snow ................................................... 5-33
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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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