1994 GMC SIERRA brakes

What can you do about highway hypnosis? First, be aware that it can
happen.
Then here are some tips:
0 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 mirrors and your instruments frequently.
0 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.
Hill and Mountain Roads
Driving on steep hills or mountains is different from driving in flat or
rolling terrain.
If you drive regularly in steep country, or if you're planning to visit there,
here are some tips that can make your trips safer and more enjoyable. (See
"Off-Road Driving" in the Index for information about driving off-road.)
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.
0 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.
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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 ability to 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.
Watch for slippery spots. The road might be fine until you hit a spot
that’s covered with ice. On an otherwise clear road, ice patches may
appear in shaded areas where the
sun can’t reach: around clumps of
trees, behind buildings, or under bridges. Sometimes the surface of
a
curve or an overpass may remain icy when the surrounding roads are
clear. If you see a patch
of ice ahead of you, brake before you are on it.
Try not to brake while you’re actually on the ice, and avoid sudden
steering maneuvers.
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I
Run your engine only as long as you must. This saves fuel. When you run
the engine, make it go a little faster than just idle. That is, push the
accelerator slightly. This uses less fuel for the heat that you get and it keeps
the battery (or batteries) charged.
You will need a well-charged battery (or
batteries) to restart the vehicle, and possibly for signaling later on with your
headlights. Let the heater run for awhile.
If you have a diesel engine, you may have to run it at a higher speed to get
enough heat. Then, shut the engine off and close
the window almost all the
way to preserve the heat. Start the engine again and repeat this only when
you feel really uncomfortable from the cold. But do it as little as possible.
Preserve the fuel
as long as you can. To help keep warm, you can get out of
the vehicle and do some fairly vigorous exercises every half hour or so until
help comes.
Power Winches
If you wish to use a power winch on your vehicle, only use it when your
vehicle
is stationary or anchored.
When operating a power winch on your vehicle, always leave the\

transmission
in "N" (Neutral). Leaving a automatic transmission
in "P" (Park) while using a power winch may damage the
transmission.
Also, leaving an automatic or manual transmission
in gear while using a power winch may damage the
transmission.
Use the regular brakes, set the parking brake, or block the wheels to keep
your vehicle
from rolling.
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Power Take-Off (PTO)
NOTICE:
If you will be using the PTO while the vehicle remains in one
place, drive the vehicle to warm it up before operating the
PTO.
Don’t use the PTO for more than four hours without driving
your vehicle again. If you don’t follow these guidelines, your
transfer case or transmission could be damaged.
NOTICE:
Don’t have a PTO that will exceed 35 horsepower installed on
your vehicle. It could damage your transmission or transfer
case.
Before using a power take-off, refer to the manufacturer’s or installer’s
instructions.
To engage a power take-oft
1. Set the parking brake.
2. Shift the transmission into “N” (Neutral).
3. Hold the clutch pedal down and engage the power take-off.
If you are going to drive
the vehicle, shift the transmission into the gear
you want.
Then shift the transfer case into the range you want (if you
have four-wheel drive), apply the regular brakes and release the
parking brake.
4. Release the clutch (and the regular brakes) as you normally would.
When
you release the clutch, the power take-off will start.
Using a Transfer Case Mounted Power Take-Off
(Manual Transmission)
1. Set the parking brake.
2. Shift the transfer case into “N” (Neutral).
3. Hold the clutch pedal down. If the vehicle will remain in the same
place, shift the transmission into the highest gear.
4. Engage the power take-off.
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If you are going to drive the vehicle, shift the transmission into th\
e gear
you want. Then shift the transfer case into the range you want, apply
the regular brakes and release the parking brake.
When you release the clutch, the power take-off will start.
5. Release the clutch (and the regular brakes) as you normally \
would.
Using a Transfer Case Mounted Power Take-Off
(Automatic Transmission)
1. Set the parking brake.
2. Shift the transfer case into “N’ (Neutral).
3. Shift the transmission into “N’ (Neutral).
4. Engage the power take-off.
If you are going to drive the vehicle, shift the transfer case into \
the
range you want. Then apply the regular brakes and release
the parking
brake.
5. Shift the transmission to “D” (Drive) to start the powe\
r take-off.
6. Release the regular brakes to drive the vehicle.
Towing a Trailer
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 section, and see your Veh\
icle
dealer for important information about towing a trailer with
your vehicle.
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from the front edge of the foot to the middle of the hitch ball socket. If
the distance is less than 12 inches, take the foot off the trailer tongue.
0 If you’ll be pulling a trailer that, when loaded, will weigh more than
4,000 pounds (1 8 14 kg) be sure to use a properly mounted,
weight-distributing hitch and sway control
of the proper size. This
equipment is very important for proper vehicle loading and good
handling
when you’re driving.
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. 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 pounds (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 your vehicle’s hydraulic brake system,
but consider
the following:
0 Will the trailer brake system use more than 0.02 cubic inch (0.3 cc) of
fluid from your vehicle’s master cylinder? If it will, don’t tap into your
vehicle’s brake system. Both braking systems won’t work well, and
you
could even lose your brakes altogether.
0 Will the trailer brake parts take 3,000 psi (20 650 kPa) of pressure? If
not, the trailer brake system must not be used with your vehicle.
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 so responsive as your vehicle is by itself.
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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 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
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
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 to turn,
change lanes or stop.
When towing a trailer, the green 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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Driving On Grades
Reduce speed and shift to a lower gear before you start down a long or
steep downgrade.
If you don’t shift down, you might have to use your
brakes
so much that they would get hot and no longer work well.
On a long uphill grade, shift down and reduce your speed to around
45 mph
(70 km/h) to reduce the possibility of engine and transmission overheating.
When towing at high altitude with steep uphill grades,you need to consider
the following information. The lower atmospheric pressure at high altitude
allows your vehicles engine coolant to boil at a lower temperature than at
normal altitudes.
If you immediately turn your engine off after towing at high altitude with
steep uphill grades, your vehicle may show signs similar
to engine
overheating.
To avoid this, let your vehicle operate in a parked position with
the transmission in
“N” (Neutral) for a few minutes before you turn off the
engine. If you do get the overheat warning, see “Engine Overheating” in
the Index.
If you have an automatic transmission, you should use
“D” (or, as you need
to, a lower gear) when towing a trailer. Operating your vehicle in
“D” when
towing a trailer will minimize heat buildup and extend the life
of your
transmission.
If you have a manual transmission and
you are towing a trailer, it’s better
not to use fifth gear. Just drive in fourth gear (or, as you need to, a lower
gear).
Parking on Hills
You really should not park your vehicle, with a trailer attached, on a hill. If
something goes wrong, your rig could start
to move. People can be injured,
and both your vehicle and the trailer can be damaged.
But if you ever have to park your rig on a hill, here’s how
to do it:
1.
2.
3.
4.
5.
6.
Apply your regular brakes, but don’t shift into “P’ (Park) yet, or in gear
for a manual transmission.
Have someone place chocks under the trailer wheels.
When the wheel chocks are in place, release the regular brakes until the
chocks absorb
the load.
Re-apply the regular brakes. Then apply your parking brake, and then
shift to
“P7, (Park), or “R” (Reverse) for a manual transmission.
If
you have a four-wheel-drive vehicle, be sure the transfer case is in a
drive gear-not in
“N7 (Neutral).
Release
the regular brakes.
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