1993 GMC SIERRA engine

I CAUTION
A Coasting downhill in N (Neutral) or with the ignition off is dangerous.
E ‘ Your brakes will have to do all the work of slowing down. They could
get
so hot that they wouldn’t work well. You could crash. Always
have your engine running and your vehicle in gear when you go
downhill.
l I
e
e
e
e
e
Know how to go uphill. You may want to shift down to a lower gear.
The lower gears help cool your engine and transmission, and yo\
u can
climb the hill better.
Stay .in your own lane when driving on two-lane roads in hills or
mountains. Don’t swing wide
or cut across the center of the road. Drive
at speeds that let you stay in your own lane. That way, you won’t be
surprised by a vehicle coming toward you in the same lane.
It takes longer to pass another vehicle when you’re going uphill. You’ll
want
to leave extra room to pass. If a vehicle is passing you and
doesn’t have enough room,
slow down to make it easier for the other
vehicle to get by.
As you go over the top of a hill, be alert. There could be something in
your lane, like a stalled car
or an accident.
You may see highway signs on mountains that warn of special problems.
Examples are long grades, passing or no-passing zones, a fallin\
g rocks
area, or winding roads. Be alert to these and take appropriate action.
Winter driving can present special problems. See “Winter Driv\
ing” in the
Index.
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Your Driving and the Road
If You’re Caught in a Blizzard
AM48002
If you are stopped by heavy snow, you could be in a serious situation. You
should probably stay with your vehicle unless you know for sur\
e that you are near help and you can hike through the snow. Here are some t\
hings
to do to
summon help and keep yourself and your passengers safe: Turn o\
n your
hazard flashers. Tie a red cloth to your vehicle to alert pol\
ice that you’ve
been stopped by the snow. Put on extra clothing or wrap a bl\
anket around
you. If you have no blankets or extra clothing, make body ins\
ulators from
newspapers, burlap bags, rags, floor mats-anything you can wrap \
around
yourself or tuck under your clothing
to keep warm.
You can run the engine to keep warm, but be careful,
I Snow can trap exhaust gases under your vehicle. This can cause\

deadly
CO (carbon monoxide) gas to get inside. CO could overcome
you and kill you. You can’t see
it or smell it, so you might not know
it is in your vehicle. Clear away snow from around the base of your
vehicle, especially any that
is blocking your exhaust pipe. And check
around again from time to time
to be sure snow doesn’t collect there.
Open a window just a little on the side of the vehicle that’\
s away
I from the wind. This will help keep CO out. I
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AM480043
Run your engine only as long as you musk. This saves fuel. When you run
the engine, make it go a little faster than just idle. That is, push the
accelerator slightly. This uses less fuel for the heat that yo\
u get and
it keeps
the battery (or batteries) charged. You will need a well-charged battery (or
batteries) to restart the' vehicle, and possibly for signaling later on with your
headlights. Let the heater run for awhile.
If you 'have a diesel engine, you
may have to run it at a higher speed
to lget enough heat. Then, shut the
engine
off and close the window almost all the way to preserve the heat.
Start the engine again and repeat this only when you feel really
uncomfortable from the cold. But
do it as little as'possible. Preserve the fuel
as long as you can.
To help keep warm, you can get out of the vehicle and
do some fairly vigorous exercises every half hour or so until help comes.
If You're Stuck in Deep Snow
This manual explains how to get the vehicle out of deep snow without
damaging it. See "Rocking Your Vehicle" in the Index.
Towing a mailer
CAUTION I
If you don't use the correct equipment and drive properly, you ca\
n
lose control when you pull a trailer. For example, if the trailer is too
heavy, the brakes may not work well-or even at all. You and your
passengers could be seriously injured. Pull a trailer only if \
you have
followed all the steps in this section.
I
i'- ." "
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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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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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CAUTION
It can be dangerous to get out of your vehicle if the shift lever is not
fully in
P (Park) with the parking brake firmly set. Your vehicle can
roll.
If you have left the engine running, the vehicle can move suddenl\
y.
You
or others could be injured. To be sure your vehicle won’t move,
when you’re on fairly level ground, use the steps that follow.
If you have four-wheel drive and your transfer case is in N (Neutral),
your vehicle will be free to
roll, even if your shift lever is in P (Park).
So, be sure the transfer case is in a drive gear-not in N (Neutral).
If you are parking on a hill, or if you’re pulling a trailer, also see
“Parking On Hills” in the Index.
When You Are Ready to Leave After Parklng 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 To wing
Your vehicle will need service more often when you’re pulling a trailer. See
the Maintenance Schedule for more on this. Things that are esp\
ecially
important in trailer operation are automatic transmission fluid (don’t overfill),
engine oil, axle lubricant, belts, cooling system, and brake ad\
justment. 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.
mailer Wiring Harness
See “Trailer Wiring Harness’’ in the Index.
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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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.
To turn off the flasher, pull out on the collar.
When the hazard warning flashers are on, your turn signals won’t work.
Other Warning Devices
If you carry reflective triangles, you can set one up at the side of the road
about
300 feet (100 m) behind your vehicle.
Jump Starting
If your battery (or batteries) has run down, you may want to use another
vehicle and some jumper cables to start your vehicle. But please follow the
steps- below
to do it safely.
CAUTION
Batteries can hurt you. They can be dangerous because: I
They contain acid that can burn you.
They contain gas that can explode c te. ..
They contain enough electricity to burn you.
n hurt you. I
If you don’t follow these ’ !ps exactly, some or all of tt- --e things
-I
To Jump Start Your Vehicle ’
1. Check the other vehicle. It must have a 12-volt battery with a negative
ground system.
If the other system isn’t a 12-volt system with a negative ground, bot
I vehicles can be damaged.
- -
If you have a diesel engine vehicle with two batteries (or more), you
should know before you begin that, especially in cold weather, you may
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