tire pressure GMC SIERRA 1997 Owners Manual

Here’s how anti-lock works. Let’s say the road is wet.
You’re driving safely. Suddenly an animal jumps out
in
front of you.
You slam on the brakes. Here’s what happens with ABS.
A computer senses that wheels are slowing down. If one
of the wheels is about
to stop rolling, the computer will
separately work the brakes at each front wheel
and at the
rear wheels. The anti-lock system can change the brake 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.
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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.
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.
Driving in Water
Light rain causes no special off-road driving problems.
But heavy rain can mean flash flooding, and flood
waters demand extreme caution.
Find out how deep
the water is before you drive through
it.
If it’s deep enough to cover your wheel hubs, axles or
exhaust pipe, don’t try it
-- you probably won’t get
through. Also, water that deep can damage your axle
and other vehicle parts.
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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
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
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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When you want to leave the freeway, move to the proper
lane well in advance. If you miss your exit, do not,
under any circumstances,
stop and back up. Drive on
to the next exit.
The exit ramp can be curved, sometimes quite sharply.
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 be well 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:
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Windshield Washer Fluid: Is the reservoir full?
Are all windows clean inside and outside?
Wiper Blades: Are they in good shape?
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?
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Loading Your Vehicle
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GAWR FRT
RIM COLD TIRE PRESSURE
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The Certificationrnire 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 GVWR
(Gross Vehicle Weight Rating). The GVWR includes the
weight
of the vehicle, all occupants, fuel and cargo.
The Certificationmire 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.
/;1 CAUTION:
In the case of a den 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.
Using heavier suspension components to get added
durability might not change your weight ratings. Ask
your dealer to help you load
your vehicle the right way.
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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:
The trailer parts can withstand 3,OOO psi (20 650 Wa)
of pressure.
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.
During your trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer brakes
are still working.
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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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6-32 Service
Fuel (Gasoline Engine)
Fuels
in Foreign Countries - - Gasoline
Engines
Filling Your Tank
Checking Things Under the Hood
Noise Control System
Engine Oil (Gasoline Engine)
Air Cleaner Filter (Gasoline Engines)
Automatic Transmission Fluid
Manual Transmission Fluid
Hydraulic Clutch
Rear Axle
Four-wheel Drive
Engine Coolant Radiator Pressure Cap (Gasoline Engine)
Thermostat 6-33
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6-64
6-68
6-69
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6-78 Power Steering Fluid
Windshield Washer Fluid
Brakes
Battery
Bulb Replacement
Windshield Wiper Blade
R
Tires
Appearance Care .eplacement
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 Specifications
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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.
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A CAUTION:
Poorly maintained and improperly used tires
are dangerous.
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.
CAUTION: (Continued)
0 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.
cut, punctured or broken by a sudden
impact
-- such as when you hit a pothole.
Keep tires at the recommended pressure.
0 Worn, old tires can cause accidents. If your
tread
is badly worn, or if your tires have
been damaged, replace them.
0 Overinflated tires are more likely to be
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Inflation -- Tire Pressure
The Certificationmire 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 km).
You can operate some vehicles at reduced inflation
pressures only when you’ll be carrying reduced loads.
On those vehicles, the minimum cold inflation pressures
for
a typical reduced load are printed on the Improved
Ride Tire Pressure label located on the driver’s door.
Weigh the vehicle to find the load on each tire and see
the label for the minimum cold inflation pressures for
that load.
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:
Too much flexing
Too much heat
0 Tire overloading
Bad wear
Bad handling
Bad fuel economy.
If your tires have too much air (overinflation),
you can get the following:
Unusual wear
Bad handling
Rough ride
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.
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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. odoff road)
than
the rear tires, don’t rotate your tires front to rear.
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