1993 GMC SIERRA change time

Tune your senses to different kinds of signals. -Your eyes, for example, meed
to constantly sweep the terrain for unexpected obstacles. Your .ears need
to
listen for unusual tire or engine sounds. With your arms, hands, feet, and
body you’ll need to respond
to vibrations and vehicle bounce.
Controlling your vehicle is the key
to successful off-road driving. One of the
best ways
to control your vehicle is to control your speed. Here .are some
things
to keep in mind. At higher speeds:
e you approach things fastar and you have less time to scan the terrain
for obstacles.
you have less time
to react. ‘I , ’C _. ’.
you have more vehicle bounce when you drive over obstacles.
you’ll need more distance for braking, especially since you’\
re on an unpaved surface.
CAUTION
When you’re driving off road, bouncing and quick changes in
direction can easily throw you out of position. This could cause you
to lose control and crash. So, whether you’re driving on or off the
road, you and your passengers should wear safety belts.
Scanning the Terrain
Off-road driving can take you over many different kinds of terrain. You need
to be familiar with the terrain and its many different features. Here are some
things
to consider.
Surface Conditions
Off-roading can ta.ke you. over hard-packed dirt, gravel, rocks,\
grass, sand, mud, snow or ice. Each of these sutfaces affects the steering, acceleration,
and braking of your vehicle in different ways. Depending upon the kind of
. surface you are on, you may experience slipping, sliding, wheel\
spinning,
delayed acceleration, poor traction, and longer braking distances\
.
Surface Obstacles
Unseen or hidden obstacles can be hazardous. A rock, log, hole, rut, or
bump can startle you if you’re not prepared for them. Often these obstacles
are hidden by grass, bushes, snow or even the rise and fall of the terrain
itself. -.Here are some things
to consider:
Is the path ahead clear?
Will the surface texture change abruptly up ahead?
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Your Driving and the Road
Does the travel take you uphill or downhill? (There’s more \
discussion of
Will you have to stop suddenly or change direction quickly? these subjects later.)
When you drive over obstacles
or rough terrain, keep a firm grip on the
steering wheel. Ruts, troughs, or other surface features can jerk the wheel
out of your hands
if you’re not prepared.
When you drive over bumps, rocks, or other obstacles, your whe\
els can leave
the ground.
If this happens, even with one or two wheels, you can’t contro\
l
the vehicle as well
or at all.
Because you will be on an unpaved surface, it’s especially \
important
to avoid
sudden acceleration, sudden turns,
or sudden braking.
In a way, off-road driving requires a different kind of alertness from driving on
paved roads and highways. There are no road signs, posted spee\
d limits
or
signal lights. You have to use your own good judgment about what is safe
and what isn’t.
* Drinking and driving can be very dangerous on any road. And this is I
1 certainly true for off-road driving. At the very time you need special
alertness and driving skills, your reflexes, perceptions and jud\
gment
can be affected by even a small amount of alcohol. You could have
a serious-or even fatal-accident
if you drink and drive or ride with
a driver who has been drinking. (See “Drunken Driving”
in the
Index.)
Driving On Off-Road Hills
Off-road driving often takes you up, down, or across a hill. Driving safely on
hills requires good judgment and an understanding of what your vehicle can
and can’t do. There are some hills that simply can’t be \
driven, no matter how
well built the vehicle.
A, Many hills are simply too steep for any vehicle. If you drive up them,
- IOU will stall. If you drive down them, you can’t control your speed. If
you drive across them, you will roll over. You could be seriously
injured or killed.
If you have any doubt about the steepness, don’t
drive the hill.
I I
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‘
Your Driving and the Road
Weather Forecasts: What’s the weather outlook along your route?
Should -you delay your trip a short time to avoid a major storm system?
Maps: Do you have up-to-date maps? . .. .. . -1 .. On fhe Road
Unless you are the only driver, ‘it is good .to share the driving task’with
others. Limit turns behind the wheel to about
100 miles (160 km) or two
hours at a sitting. Then, either change drivers or stop for s\
ome- refreshment
like coffee, tea or soft drinks and some limbering up. But do\
stop and move
around. Eat lightly along the way. Heavier meals tend
to make some people
sleepy.
.. . .- , - .~
On two-lane highways or undivided multilane highways that do no\
t have
controlled access, you’ll want to watch for some situations \
not usually found
on freeways. Examples are: stop signs and signals, shopping cen\
ters with
direct access to the highway, no passing zones and school zone\
s, vehicles
turning’ left and right
off the road, pedestrians, cyclists, parked vehicles, and
even animals.
Highway Hypnosis
Is there actually such a condition as “highway hypnosis?” Or \
is it just plain ,
falling asleep at the wheel? Call it highway hypnosis, lack of awareness, or
whatever.
’ There is something about an easy stretch of road with the sam\
e scenery,
along with the hum
of the tires on the road, the drone of the engine, and the
, rush of the wind against the vehicle that can make you sleepy\
. Don’t let it ’.
happen to you! If it does, your vehicle can leave the road in less than a
second,
and you could crash and be injured.
What can you do about highway hypnosis? First, be aware that it
can
happen.
Then here are some tips:
Make sure your vehicle is well - ventilated, with a comfortably cool interior.
Keep your eyes moving. Scan the road ahead and to the sides. \
Check
your rearview mirrors frequently and your instruments from time \
to time.
This can help you avoid a fixed stare.
-
,x ! - : ,-.:.&---z-.- ..* .-7
0 d
Wear good sunglasses in bright light. Glare can cause drowsiness. But
don’t wear sunglasses at night. They will drastically reduce \
your overall
-%
vision at the very time you need all the s.eeing power you h\
ave.
If you get sleepy, pull off the road into a rest, service, or parking area
and take a nap, get some exercise, or both. For safety, treat\
drowsiness
on the highway as an emergency.
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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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I CAUTION
Sust or dirt on the wheel, or on the parts to which it is fastened,
could come
off and cause an accident. When you change a wheel,
remove any rust or dirt from the places where the wheel attac\
hes to
the vehicle. In an emergency, you can use a cloth or a paper towel
to
do this; but be sure to use a scraper or wire brush later- if vou
need to, to get all the rust or dirt
off.
A :an make the wheel nuts become loose after a time. The wheel
Remove any rust
or dirt from the wheel bolts, mounting surfaces or spare
wheel. Place the spare on the wheel mounting surface.
1 CAUTION I
Never use oil or grease on studs or nuts. If you do, the nuts migh
come loose. Your wheel could fall
off, causing a serious accident.
K2530
Replace the wheel nuts with the rounded end of the nuts toward the wheel.
Tighten each wheel nut by hand until the wheel is held against the hub.
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Service & Appearance Care
This light also should come on when you start your engine, as\
a check. If it
doesn’t, have it fixed
so it will be there to let you know if you ever do get
water in your fuel.
If the light comes on at any other time, use this chart.
“WATER IN FUE
PROBLEM
Light comes on intermittently.
1) Temperatures above freezing.
Light stays on
2) Temperatures below freezing.
3) Immediately after refueling -
Large amounts of water
probably pumped into the
tank.
.” LIGHT CHART
RECOMMENDED ACTION
Drain water from fuel filter.
Drain fuel filter immediately.
If nc
water is drained and light stays on
-
replace fuel filter.
Drain fuel filter immediately.
If no
water can be drained
- water may be
frozen. Open air bleed
to check for
fuel pressure.
If no fuel pressure
replace filter.
Fuel tank purging required. See your
dealer for assistance.
1
iesitation or “flat” performance at high speed or hard acceleration may be an
ndication of premature fuel filter plugging due to dirty
or contaminated fuel.
The filter element may need
to be changed if this happens. See your dealer
or assistance.
f you drive when this warning light is on, you can damage your fuel I
njection system and your engine. If the light comes on right after you
efuel,
it means water was pumped into your fuel tank. Turn off your
mgine immediately. Then, have the water drained at once.
I
To drain water:
1. Remove the fuel tank cap.
2. Connect a hose going from the water drain valve to a fuel-resistant
container.
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2. Unplug the Shut-Off solenoid wire from the fuel pump to prevent the
engine from starting.
3. With the air bleed valve open, turn your ignition key to Start for 10 to
15 seconds to crank (but not start) your engine. Keep doing this until
you can just see some clear fuel at the air bleed valve.
I A Diesel fuel is flammable. It could start a fire if it gets on hot engine
b parts. You could be burned. Don’t let too much fuel flow from the air
bleed valve or screw, and wipe up any spilled fuel with a cloth.
4. Close the air bleed valve, or replace the screw and reconnect \
the
Shut-Off solenoid wire.
5. Turn the ignition key to Start for 10 to 15 seconds at a time until your
engine starts.
Fuel Filter Replacement (6.5L Diesel Engines)
If you want to change the fuel filter yourself, here’s how \
to do it:
1 CAUTION
A Diesel fuel is flammable. It could start a fire if something ignites it,
-L and you could be burned. Don’t let it get on hot .engine parts, and
I keep matches or other ignition sources away.
1. Turn off your engine and set your parking brake.
2. Take off the fuel tank cap. This releases pressure in the tank.
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These numbers on an oil container show its viscosity, or thickness.
Do not use other viscosity oils such as
SAE IOW-40 or SAE 2OW-50.
Energy Conserving II
Oils with these words on the container will help you save fuel.
This doughnut-shaped logo (symbol) is used on most oil containers to help
you select the correct oil.
You should look for this on the oil container, and use
only those oils that
display the logo.
GM Goodwrench@ oil (in Canada, GM Engine Oil) meets all the requirements
for your vehicle.
Engine Oil Additives:
Don’t add anything to your oil. Your GM dealer is ready to advise if you think
something should be added.
When to Change Engine Oil:
See if any one of these is true for you:
Most trips are less than 4 miles (6 km).
It’s below freezing outside and most trips are less than 10 miles
(16 km).
The engine is at low speed most of the time (as in door to door
delivery, or in stop-and-go traffic).
You tow a trailer often.
Most trips are through dusty places.
The vehicle is frequently operated off-road.
If any one of these is true for your vehicle, then you need to change your
oil and filter every 3,000 miles (5000 km) or 3 months-whichever comes
first.
Vehicles with Light Duty Emissions (8500 GVWR or less).
If none of them is true, change the oil every 7,500 miles (12 500 km) or 12
months-whichever comes first. Change the filter at the first oil change and at
every other oil change after that.
Vehicles with Heavy Duty Emissions (8501 GVWR or more).
If none of them is true, change the oil every 6,000 miles (10 000 km) or 12
months-whichever comes first. Change the filter at the first oil change and at
every other oil change after that
‘if mileage determines when you change your
oil.
If time determines when you change your oil, change the filter ea\
ch time
you change your oil.
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