1993 CHEVROLET SUBURBAN service

Your Driving and the Road
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.
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 seeing power you have.
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.
As in any driving situation, keep pace with traffic and allow ade\
quate
following distances.
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. .
6. Release the regular brakes.
CAUTION
It can be dangerous to get out of your vehicle if the shift lever is no
fully in
P (Park) wi-. 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 foll\
ow.
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
I “Parking On Hills” in the Index. I
When You Are Ready to Leave After Parking 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 stow the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re pulling a \
trailer. .See
the Maintenance Schedule for more on this. Things that are especially
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.
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Good Battery Dead Battery
4
K2506
10. Now start the vehicle with the good battery and run the engin\
e for
11. Try to start the vehicle with the dead battery.
awhile.
If it won’t start after a few tries, it probably needs service.
12. Remove the cables in reverse order to prevent electrical shorti\
ng.
Take
REMOVE CABLES IN THIS ORDER I
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Tiwing 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
damage.
If your vehicle has been changed since it was factory-new, by adding things
like fog lamps, aero skirting,
or special tires and wheels, these 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
If there was an accident, what was damaged.
case,
if you have one.
CAUTION I
To help avoid
injury to you or others:
A 9 Never let passengers ride in a vehicle that is being towed.
e Never tow faster than safe or posted speeds.
e 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
Neutral 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 kmlh) or farther than 50 miles (80
km) 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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If No Steam Is Coming From Your C gine:
If you get the overheat warning but see or hear no steam, the problem may
not be too serious. Sometimes the engine can get a little too hot when you:
Climb a long hill on a hot day.
Stop after high speed driving.
Idle for long periods in traffic.
Tow a trailer.
If you get the overheat warning with no sign of steam, try this for a minute
or so:
1. If you have an air conditioner, turn it off.
2. Turn on your heater to full hot at the highest fan speed and open the
3. If you’re in a traffic jam, shift to N (Neutral).
window
as necessary.
If you no longer have the overheat warning, you can drive. Just to be safe,
drive slower for about ten minutes.
If the warning doesn’t come back on, you
can drive normally.
If the warning continues, pull over, stop, and park your vehicle right away.
If there’s still no sign of steam, push the accelerator until the engine speed is
about twice as fast as normal idle speed. Bring the engine speed back to
normal idle speed after two or three minutes.
Now see if the warning stops.
But then,
if you still have the warning, TURN OFF THE ENGINE AND GET
EVERYONE
OUT OF THE VEHICLE until it cools down.
You may decide not
to lift the hood but to get service help right away.
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The coolant level should be at or above COLD. If it isn’t, you may have a
leak in the radiator hoses, heater hoses, radiator, water pump or somewhere
else in the cooling system.
CAUTION
A
Heater and radiator hoses, and other engine parts, can be very\
hot.
Don’t touch them. If you
do, you can be burned.
Don’t run the engine
if there is a leak. If you run the engine, 1‘ it coulc
lose all coolant. That could cause an engine fire, and you could
be
I burned. Get any leak fixed before you drive the vehicle.
I
If there seems to be no leak, check to see if the electric engine fan (if you
have one) is running. If the engine is overheating, the fan \
should be running.
If
it isn’t, your vehicle needs service.
Start the engine again to see
if the regular fan runs when the engine does.
If
it doesn’t, your vehicle needs service. Turn off the engine.
How to Add Coolant to the Coolant Recovery Tank
If you haven’t found a problem yet, but the coolant level \
isn’t at or above
COLD, add a 50150 mixture of clean water (preferably distilled) and a proper
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Service & Appearance Care
.
Here you will find information about the care of your vehicle . This section
begins with service and fuel information. and then it shows
how to check
important fluid and lubricant levels
. There is also technical information about
your vehicle. and a section devoted to its appearance care
.
Service ........................................................................\
........................................... 6-3
Fuel ........................................................................\
................................................ 6-4
Checking Things Under the Hood
....................................................................... \
6-8
Hood Release
........................................................................\
............................ 6-8
Engine Oil ........................................................................\
.................................. 6-9
Air Cleaner
........................................................................\
............................... 6-16
Automatic Transmission Fluid
........................................................................\
. 6-17
Manual Transmission Fluid ........................................................................\
..... 6-20
Hydraulic Clutch
........................................................................\
....................... 6-21
Transfer Case
........................................................................\
.......................... 6-23
Front
Axle ........................................................................\
................................. 6-24
Rear Axle
........................................................................\
................................. 6-24
Engine Coolant
........................................................................\
........................ 6-25
Power Steering Fluid
........................................................................\
............... 6-29
Windshield Washer Fluid
........................................................................\
......... 6-31
Brake Master Cylinder
........................................................................\
............. 6-32
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Service & Appearance Care
Replacing Brake System Parts ........................................................................\
.. 6-33
Other Maintenance Items
........................................................................\
........... 6-34
Lubrication
........................................................................\
.................................... 6-35
Electrical System
........................................................................\
......................... 6-37
Battery
........................................................................\
...................................... 6-37
Bulb Replacement
........................................................................\
.................... 6-37
Fuses and Circuit Breakers
........................................................................\
.... 6-43
Exhaust System
........................................................................\
........................... 6-45
Loading Your Vehicle
........................................................................\
.................. 6-46
Tires
........................................................................\
.............................................. 6-48
Inflation-Tire Pressure
........................................................................\
........... 6-49
Tire Inspection and Rotation
........................................................................\
.. 6-52
When It’s Time for New Tires ........................................................................\
6-53
Buying New Tires
........................................................................\
.................... 6-53
Uniform Tire Quality Grading
........................................................................\
.. 6-54
Wheel Alignment and Tire Balance
............................................................... 6-55
Wheel Replacement
........................................................................\
................. 6-55
Tire Chains
........................................................................\
............................... 6-56
Appearance Care
........................................................................\
........................ 6-57
Cleaning the Inside Of Your Vehicle
............................................................. 6-58
Cleaning the Outside
Of Your Vehicle .......................................................... 6-61
Appearance Care Materials
........................................................................\
........ 6-64
Vehicle Identification Number
........................................................................\
..... 6-65
Service Parts Identification Label
...................................................................... 6-67
Specification Charts ........................................................................\
..................... 6-68
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