1998 GMC SIERRA brakes

Rain and wet roads can mean driving trouble. On a wet
road,
you can’t stop, accelerate or turn as well because
your tire-to-road traction
isn’t as good as on dry roads.
And, if your tires don’t have much tread left, you’ll get
even less traction. It’s always wise to go slower and be
cautious if rain starts to fall while
you are driving. The
surface may get wet suddenly when your reflexes are
tuned for driving on dry pavement.
The heavier the rain, the harder
it is to see. Even if your
windshield wiper blades are in good shape, a heavy rain
can make it harder to see road signs and traffic signals,
pavement markings, the edge of the road and even
people walking.
It’s wise
to keep your wiping equipment in good shape
and keep your windshield washer tank filled with
washer fluid. Replace your windshield wiper inserts
when
they show signs of streaking or missing areas on
the windshield, or when strips of rubber start to separate
from the inserts. Driving too fast
through large water puddles or even
going through some car washes can cause problems, too.
The water may affect your brakes. Try to avoid puddles.
But if you can’t, try to slow down before you hit them.
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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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0
0
Keep your vehicle in good shape. Check all fluid
levels and also the brakes, tires, cooling system and
transmission. These parts can work hard on
mountain roads.
Know how to go down hills. The most important
thing to know
is this: let your engine do some of the
slowing down. Shift to
a lower gear when you go
down a steep or long hill.
I A CAJTION: I
If you don’t shift down, your brakes could get so
hot that they wouldn’t work well. You would then
have poor braking or even none going down
a hill.
You could crash. Shift down to let your engine
assist your brakes on a steep downhill slope. Coasung
aownhill in NEUTRAL
(N) or with the
ignition
off is dangerous. Your brakes will have
to do all the work
of slowing down. They could
get
so hot that they wouldn’t work well. You
would then have poor braking or even none going
down
a hill. You could crash. Always have your
engine running and your vehicle in gear when
you go downhill.
0
0
Know how ro g6 uphill. You may want to shift down
to a lower gear.
The lower gears help cool your engine
and transmission, and you 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.
0
0 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 falling rocks area or winding
roads. Be alert
to these and take appropriate action.
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Driving on Snow or Ice
Most of the time, those places where your tires meet the
road probably have good traction.
However, if there is snow or ice between your tires and
the road,
you can have a very slippery situation. You’ll
have a
lot less traction or “grip” and will need to be
very careful. What’s the worst time
for this? “Wet ice.” Very cold
snow or ice can be slick and hard to drive
on. But wet
ice can be even more trouble because it may offer the
least traction of all. You
can get wet ice when it’s about
freezing
(32°F; 0°C) and freezing rain begins to fall.
Try to avoid driving
on wet ice until salt and sand crews
can get there.
Whatever
the condition -- smooth ice, packed, blowing
or loose snow
-- drive with caution.
Accelerate gently. Try not to break the fragile traction. If
you accelerate too fast, the drive wheels will spin and
polish the surface under the tires even more.
Your anti-lock brakes improve your vehicle’s stability
when
you make a hard stop on a slippery road. Even
though you have
an anti-lock braking system, you’ll
want to begin stopping sooner than you would on dry
pavement. See “Anti-Lock‘’ in the Index.
Allow greater following distance on any
slippery road.
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If your slide-in camper and its load weighs less than the
CWR, the center
of gravity zone for your vehicle may
be larger.
Your dealer can help you make a good vehicle-camper
match. He’ll also help
you determine your CWR.
After you’ve loaded your vehicle and camper, drive to a
weigh station and weigh the front and rear wheels
separately. This will tell you
the loads on your axles.
The loads on the front and rear axles shouldn’t be more
than either of
the GAWRs. The total of the axle loads
should
not be more than the GVWR.
Open your driver’s door and look at the
CertificatiodTire label to find
out your GAWR
and GVWR.
If you’ve gone over your weight ratings, move or take
out some things until all the weight falls below the
ratings.
Of course, you should always tie down any
loose items when you load your vehicle or camper. When you
install and load your slide-in camper, check
the manufacturer’s instructions.
If you want more information
on curb weights, cargo
weights, Cargo Weight Rating and the correct center of
gravity zone for your vehicle, your dealer can help
you.
Just ask for a copy of “Consumer Information,
Truck-Camper Loading.”
Trailer Recommendations
You must subtract your hitch loads from the CWR for
your vehicle. Weigh your vehicle with the trailer attached,
so that you won’t go over the GVWR or GAWR.
You’ll get the best performance if you spread out the
weight
of your load the right way, and if you choose the
correct hitch and trailer brakes.
For more information, see “Trailer Towing”
in the Index.
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Towing a Trailer
If you don’t use the correct equipment and drive
properly, you can 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. Ask your dealer for advice
and information about towing a trailer with
your vehicle.
NOTICE:
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 part, and see your dealer for
important information about towing a trailer
with your vehicle.
Every vehicle is ready for some trailer towing. If yours
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 changes
in handling, durability and fuel economy. Successful,
safe trailering takes correct equipment, and it has to be
used properly.
That’s the reason for this part. 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.
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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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During your trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer brakes
are still working.
Following Distance
Stay at least twice as far behind the vehicle ahead as you
would 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 go 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
to the left, just move that 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
I NOTICE:
Making very sharp turns while trailering could
cause the trailer to come in contact with the
vehicle. Your vehicle could be damaged. Avoid
making very sharp turns while trailering.
When you’re turning with a trailer, make wider turns than
normal. Do this
so your trailer 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
The arrows on your instrument panel will flash
whenever
you signal a turn or lane change. Properly
hooked up, the trailer lamps will also flash, telling other
drivers you’re about to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument
panel
will flash for turns even if the bulbs on the trailer are
burned out. Thus,
you may think 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.
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