tire pressure GMC SIERRA 1998 Owners Manual

The anti-lock system can change the brlzke pressure faster
than any driver could. The computer is programmed
to
make the most of available tire and road conditions.
You can steer around the obstacle while braking hard.
As you brake, your computer keeps receiving updates on
wheel speed and controls braking pressure accordingly. Remember: Anti-lock doesn’t change the
time you need
to get your foot
up to the brake pedal or always decrease
stopping distance.
If you get too close to the vehicle in
front of you, you won’t have time to apply your brakes
if that vehicle. suddenly slows or stops. Always leave
enough room
up ahead to stop, even though you have
anti-lock brakes.
Using Anti-Lock
Don’t pump the brakes. Just hold the brake pedal down
firmly and let anti-lock work for you.
You may feel the
brakes vibrate, or you may notice some noise, but this is
normal. On vehicles
with four-wheel drive, your
anti-lock brakes work at all times
-- whether you are in
two-wheel drive or four-wheel drive.
Braking in Emergencies
With anti-lock, you can steer and brake at the same
time. In many emergencies, steering can help you more
than even the very best braking.
Steering
Power Steering
If you lose power steering assist because the engine
stops
or the system is not functioning, you can steer but
it will take much more effort.
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I-
I A CAUTION:
-
~ Getting out on the downhill (low) side of a vehicle
~ stopped across an incline is dangerous. If the
vehicle
rolls over, you could be crushed or killed.
Always get out on the uphill (high) side of the
~ vehicle and stay well clear of the rollover path.
Driving in Mud, Sand, Snow or Ice
When you drive in mud, snow or sand, your wheels
won’t get good traction. You can’t accelerate
as
quickly, turning is more difficult, and you’ll need
longer braking distances.
It‘s best to use a low gear when you’re
in mud -- the
deeper the mud, the lower the gear.
In really deep mud,
the idea
is to keep your vehicle moving so you don’t
get stuck.
When you drive on sand, you’ll sense
a change in wheel
traction. But
it will depend upon how loosely packed the
sand is. On loosely packed sand (as on beaches or sand
dunes) your tires will tend to sink into the sand. This has
an
effect on steering, accelerating and braking. You may
want to reduce the air pressure in your tires slightly
when driving on sand. This will improve traction.
Hard packed snow and ice offer the worst tire traction.
On these surfaces, it’s very easy to lose control. On wet
ice, for example, the traction is
so poor that you will
have difficulty accelerating. And
if you do get moving,
poor steering
and difficult braking can cause you to slide
out of control.
r A CAUTION:
Driving on frozen lakes, ponds or rivers can be
dangerous. Underwater springs, currents under
the ice, or sudden thaws can weaken the ice. Your
vehicle could fall through the ice and you and
your passengers could drown. Drive your vehicle
on safe surfaces only.
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J L
Wet brakes can cause accidents. They won’t work
as well in a quick stop and may cause pulling to
one side. You could lose control
of the vehicle.
After driving through
a large puddle of water or
a car wash, apply your brake pedal lightly until
your brakes work normally.
Hydroplaning
Hydroplaning is dangerous. So much water can build up
under your tires that they can actually ride
on the water.
This can happen if the road
is wet enough and you’re
going
fast enough. When your vehicle is hydroplaning,
it has little or no contact with the road.
Hydroplaning doesn’t happen often. But it can if your
tires do not have much tread or if the pressure in
one or
more
is low. It can happen if a lot of water is standing on
the road. If you can see reflections from trees, telephone
poles or other vehicles, and raindrops “dimple” the
water’s surface, there could be hydroplaning. Hydroplaning usually happens at higher
speeds, There
just
isn’t a hard and fast rule about hydroplaning. The
best advice
is to slow down when it is raining.
Driving Through Deep Standing Water
c
NOTICE:
If you drive too quickly through deep puddles or
standing water, water can come in through your
engine’s air intake and badly damage your
engine. Never drive through water that is slightly
lower than the underbody
of your vehicle. If you
can’t avoid deep puddles or standing water, drive
through them very slowly.
Some Other Rainy Weather Tips
0 Besides slowing down, allow some extra following
distance. And be especially careful when you pass
another vehicle. Allow yourself more clear room
ahead, and be prepared to have your view restricted
by road spray.
0 Have good tires with proper tread depth. (See
“Tires”
in the Index.)
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The exit speed is usually posted.
Reduce your speed according
to your speedometer, not
to your sense of motion. After driving for any distance
at higher speeds,
you may tend to think you are going
slower than you actually are.
Before Leaving on a Long Trip
Make sure you’re ready. Try to oe wed rested. If you
must start when you’re not fresh
-- such as after a day’s
work
-- don’t plan to make too many miles that first part
of the journey. Wear comfortable clothing and shoes you
can easily drive in.
Is your vehicle ready for a long trip? If you keep it
serviced and maintained, it’s ready to
go. If it needs
service, have
it done before starting out. Of course,
you’ll find experienced and able service experts in
GM
dealerships all across North America. They’ll be ready
and willing
to help if you need it.
Here are some things you can check before a trip:
0 Windshield Washer Fluid: Is the reservoir full? Are
all windows clean inside and outside?
Wiper Blades: Are they in good shape?
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0
0
0
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Fuel, Engine Oil, Other Fluids: Have you checked
all levels?
Lamps: Are they all working? Are the lenses clean?
Tires: They are vitally important to a safe,
trouble-free trip.
Is the tread good enough for
long-distance driving? Are the tires all inflated to the
recommended pressure?
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?
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
same 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 n second, and you could crash and be injured.
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Loading Your Vehicle
~EE ~NER'S MANUAL FOR ADDITIONAL INFORMATION. TI
The CertificatiodTire label is found on the rear edge of
the driver's door or in the Incomplete Vehicle Document
in the cab.
The label shows the size of your original tires and the
inflation pressures needed to obtain the gross weight
capacity
of your vehicle. This is called the Gross Vehicle
Weight Rating (GVWR). The GVWR includes the
weight
of the vehicle, all occupants, fuel and cargo.
The CertificatiodTire 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.
Never exceed the GVWR
for your vehicle, or the
GAWR for either the front or rear axle.
And,
if you do have a heavy load, you should spread
it out.
A CAUTION:
In the case of a sudden stop or collision, things
carried in the bed of your truck could shift
forward and come into the passenger area,
injuring
you and others. If you put things in the
bed of your truck, you should make sure they are
properly secured.
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Safety Chains
You should always attach chains between your vehicle
and your trailer. Cross the safety chains under the tongue
of the trailer so that’the tongue will not drop to the road
if it becomes separated from the hitch. Instructions
about safety chains may be provided by the hitch
manufacturer or by the trailer manufacturer. Follow the
manufacturer’s recommendation for attaching safety
chains and do not attach them to the bumper. Always
leave just enough slack
so you can turn with your rig.
And, never allow safety chains
to drag on the ground.
Trailer Brakes
If your trailer weighs more than 1,000 Ibs. (450 kg)
loaded, then it needs its own brakes
-- and they must be
adequate. Be sure to read and follow the instructions for
the trailer brakes so you’ll be able to install, adjust and
maintain them properly.
Your trailer brake system can tap into the vehicle’s
hydraulic brake system only if
0 The trailer parts can withstand 3,000 psi
(20 650 kPa) of pressure.
0 The trailer’s brake system will use less than
0.02 cubic inch (0.3 cc) of fluid from your vehicle’s
master cylinder. Otherwise, both braking systems
won’t work well. You could even lose your brakes.
If everything checks out this far, make the brake tap at
the port
on the master cylinder that sends the fluid to the
rear brakes.
But don’t use copper tubing for this. If you
do,
it will bend and finally break off. Use steel
brake tubing.
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 as
responsive as your vehicle
is by itself.
Before you start, check
the trailer hitch and platform
(and attachments), safety chains, electrical connector,
lamps, 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.
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Section 6 Service and 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 part devoted to its appearance care.
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6-3
6-5
6-6
6- 8
6-9
6- 13
6- 14
6-18
6-2
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6-24
6- 25
6-26
6-26
6-28 6-32
6-32 Service
Fuel (Gasoline Engine)
Fuels
in Foreign Countries (Gasoline Engines)
Filling Your Tank (Gasoline Engine)
Filling a Portable Fuel Container
Checking Things Under the Hood
Noise Control System
Engine Oil (Gasoline Engine)
Air Cleaner Filter (Gasoline Engine)
Automatic Transmission Fluid
Manual Transmission Fluid
Hydraulic Clutch
Rear Axle
Four-wheel Drive
Engine Coolant Radiator Pressure Cap (Gasoline Engine)
Thermostat
, 6-33
6-3 3
6-35
6-39
6-39
6-50
6-5
1
6-6 1
6-62
6-65 6-69
6-70
6-70
' 6-76
6-77 6-79 Power
Steering Fluid
Windshield Washer Fluid
Brakes
Battery
Bulb Replacement
Windshield Wiper Blade Replacement
Tires
Appearance Care
Cleaning the Inside
of Your Vehicle
Cleaning the Outside of Your Vehicle
Appearance Care Materials Chart
Vehicle Identification Number (VIN)
Electrical System Replacement
Bulbs
Capacities and Specifications
Air Conditioning Refrigerants
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Tires
Your new vehicle comes with high-quality tires made by
a leading tire manufacturer.
If you ever have questions
about your tire warranty and where to obtain service, see
your
GM Warranty booklet for details.
A CAUTION:
Poorly maintained and improperly used tires
are dangerous.
0
0
0
0
Overloading your tires can cause
overheating as
a result of too much friction.
You could have an air-out and
a serious
accident. See “Loading Your Vehicle” in
the Index. Underinflated tires pose the same danger as
overloaded tires. The resulting accident could cause serious injury. Check all tires
frequently to maintain the recommended
pressure. Tire pressure should be checked when your tires are cold.
Overinflated tires are more likely to be cut,
punctured
or broken by a sudden impact --
such as when you hit a pothole. Keep tires
at the recommended pressure.
Worn, old tires can cause accidents. If your
tread is badly worn, or if your tires have
been damaged, replace them.
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Inflation -- Tire Pressure
The CertificationlTire label, which is on the rear edge of
the driver’s door, or on the incomplete vehicle document
in the cab, shows the correct inflation pressures for your
tires when they’re cold.
“Cold” means your vehicle has
been sitting for at least three hours or driven no more
than
1 mile (1.6 krn).
NOTICE:
Don’t let anyone tell you that underinflation or
overinflation is all right.
It’s not. If your tires
don’t have enough
air (underinflation), you can
get the following:
0 Too much flexing
Too much heat
0 Tire overloading
0 Bad wear
Bad handling
0 Bad fuel economy.
If your tires have too much air (overinflation),
you can get the following:
0 Unusual wear
0 Bad handling
0 Rough ride
0 Needless damage from road hazards.
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When to Check
Check your tires once a month or more. Also, check the
tire pressure of the spare tire.
How to Check
Use a good quality pocket-type gage to check tire
pressure. You can’t tell if your tires are properly inflated
simply by looking at them. Radial tires may
look
properly inflated even when they’re underinflated.
Be sure
to put the valve caps back on the valve stems.
They help prevent leaks by keeping out dirt and moisture.
Tire Inspection and Rotation
Tires should be rotated every 6,000 to 8,000 miles
(10 000 to 13 000 km). Any time you notice unusual
wear, rotate your tires as soon as possible and check
wheel alignment.
Also check for damaged tires or
wheels.
See “When It‘s Time for New Tires” and
“Wheel Replacement” later in this section for more
information. If your vehicle has dual rear wheels, also
see “Dual Tire Operation” later
in this section. The purpose
of regular rotation
is to achieve more
uniform wear
for all tires on the vehicle. The first
rotation is the most important. See “Scheduled
Maintenance Services”
in the Index for scheduled
rotation intervals.
1
FRT FRT
[x[
If your vehicle has single rear wheels, always use one of
the correct rotation patterns shown here when rotating
your tires.
If your vehicle has front tires with different load ranges
or tread designs (such as all season vs. on/off road) than
the rear tires, don’t rotate your tires front
to rear.
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