1994 GMC SIERRA brake

A rear blowout, particularly on a curve, acts much like a skid and may
require the same correction you’d use in
a skid. In any rear blowout, remove
your foot from the accelerator pedal. Get
the vehicle under control by
steering the way you want the vehicle to go. It may be very bumpy and
noisy, but you can still steer. Gently brake to a stop, well \
off the road if
possible.
If a tire goes flat, the next section shows how to use your jac\
king equipment
to change a flat tire safely.
Changing a Flat Tire
If a tire goes flat, avoid further tire and wheel damage by driving slowly to a
level place. Turn
on your hazard warning flashers.
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Checking Things Under the Hood (continued)
Windshield Washer Fluid
................................. 6-45
Brake Master Cylinder
................................... 6-46
Replacing Brake System Parts
................................ 6-49
Other Maintenance Items
.................................... 6-49
Windshield Wiper Blade Inserts
.............................. 6-50
FluidLeakCheck
.......................................... 6-51
Lubrication
............................................... 6-51
Battery .................................................. 6-52
Vehiclestorage
......................................... 6-52
Bulb Replacement
......................................... 6-53
Fuses and Circuit Breakers
.................................. 6-62
Exhaustsystem
........................................... 6-64
Loading Your Vehicle
...................................... 6-64
Tires .................................................... 6-71
Inflation-Tire Pressure
.................................. 6-71
Tire Inspection and Rotation
............................... 6-73
When it’s Time for New Tires
............................. 6-74
Buying New Tires
....................................... 6-76
Uniform Tire Quality Grading
............................. 6-77
Wheel Alignment and Tire Balance
......................... 6-78
Wheel Replacement
..................................... 6-78
Tire Chains
............................................ 6-79
Appearancecare
.......................................... 6-80
Cleaning the Inside of Your Vehicle
......................... 6-81
Cleaning the Outside
of Your Vehicle ....................... 6-84
Appearance Care Materials
.................................. 6-87
Vehicle Identification Number
................................ 6-88
Service Parts Identification
Label ............................. 6-90
Specifications Charts
..................................... 6-91
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If the light comes on at any other time, use this chart.
“Water in Fuel” Light Chart
Problem
Light comes on intermittently.
Light stays on:
1. At temperatures above
freezing.
2. At temperatures below
freezing.
Recommended Action
Drain water from fuel filter.
Drain fuel filter immediately. If no
water
can be drained and light stays
on, see your dealer for assistance.
Drain fuel filter immediately. If no
water can be drained
- water may
be frozen. Open the air bleed valve
to check
for fuel pressure. If no fuel
pressure is present, replace the
fuel
filter.
3. Immediately after refueling - Fuel tank purging required. See
large amount of water possibly your dealer for assistance.
pumped into fuel tank.
Hesitation or “flat” performance at high speed or during hard acceleration
may be an indication of premature fuel filter plugging due
to dirty or
contaminated fuel, The filter element may need to be changed
if this
happens. See your dealer for assistance.
NOTICE:
If you drive when this warning light is on, you can damage y\
our
fuel injection system and your engine. If the light comes on right
after you refuel,
it means water was pumped into your fuel tank.
Turn off your engine immediately. Then, have the water drained \
at once.
To drain water:
1. Stop and park the vehicle in a safe place. Turn off the engine and apply
the parking brake.
2. Remove the fuel tank cap.
3. Place a fuel-resistant container under the filter drain hose.
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A CAUTION:
Diesel fuel is flammable. It could start a fire if it gets on hot
engine parts. You could be burned. Don’t let too much fuel flow
from the air bleed valve, and wipe up any spilled fuel with
a
cloth.
3. Close the air bleed valve.
4. Turn the ignition key to “Start” for 10 to 15 seconds at a time until your
engine starts.
Fuel Filter Replacement (Diesel Engines)
If you want to change the fuel filter yourself, here’s how to do it:
Before you remove the filter, drain any water that may have collected in the
fuel filter or filter head. See “Water in Fuel” earlier in this section to find
out how to remove water from the fuel system.
Then, drain
fuel from the filter by opening the air bleed valve and the water
drain valve. This prevents the fuel from spilling as
you replace the filter.
Drain the fuel into
a fuel-resistant container and dispose of it properly.
A CAUTION:
Diesel fuel is flammable. It could start a fire if something ignites
it, and you could be burned. Don’t let it get on hot engine parts,
and keep matches or other ignition sources away.
I. Turn off the engine and apply the parking brake.
2. Take off the fuel tank cap. This releases vacuum in the tank.
3. The filter is located at the rear of the intake manifold.
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Things that burn can get on hot engine parts and start a fire.
These include liquids like gasoline or diesel fuel, oil, coolant,
brake fluid, windshield washer and other fluids, and plastic or
rubber. You or others could be burned. Be careful not to drop or
I spill things that will burn onto a hot engine.
Before closing the hood, be sure all filler caps are on properly. Pull down
the hood and close it firmly.
Cleaning Your Diesel Engine
NOTICE:
If you spray or pour water or any other liquid on your engine
when it is warm or hot, or when it is running,
you could cause
serious damage to it.
If you ever clean the engine, clean it only
when it is cold.
Noise Control System
The following information relates to compliance with Federal noise
emission standards for vehicles
with a Gross Vehicle Weight Rating
(GVWR) of more than
10,000 pounds (4 536 kilograms). The Maintenance
Schedule booklet provides information on maintaining the noise control
system to minimize degradation
of the noise emission control system during
the life of your vehicle. The noise control system warranty
is given in your
Warranty hooklet.
These standards apply only to vehicles sold
in the United States.
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I NOTICE:
Too much or too little fluid can damage your transmission. Too
much can mean that some of the fluid could come out and fall on
hot engine parts or exhaust system, starting
a fire. Be sure to get
an accurate reading
if you check your transmission fluid.
Wait at least 30 minutes before checking the transmission fluid level if you
have been driving:
0 When outside temperatures are above 90°F (32°C).
At high speed for quite a while.
0 In heavy traffic - especially in hot weather.
While pulling a trailer.
IU get the right reading, the fluid should be at normal operating
temperature, which
is 180°F to 200°F (82°C to 93°C).
To check trunsmissioltfluid hot: Get the vehicle warmed up by driving
about
15 miles (24 km) when outside temperatures are above 50°F (1 0°C).
If it’s colder than
50°F (lO”C), drive the vehicle in “D” (3rd Gear) until the
engine temperature gage moves and then remains steady for ten minutes.
Then follow
the hot check procedures.
To check trmzsnzissiorz jZuid cold: A cold check is made after the vehicle has
been sitting for eight hours
or more with the engine off and is used only as a
reference. Let
the engine run at idle for five minutes if outside temperatures
are
50°F ( 10°C) or more. If it’s colder than 50°F (lO”C), you may have to
idle the engine longer. Should the fluid level be low during a cold check,
you must perform a hot check before adding fluid. This will give you a
more accurate reading of the fluid level.
To check the fluid hot or cold
Park your vehicle on a level place.
With the parking brake applied, place the shift lever in “P” (Park).
With your foot on the brake pedal, move the shift lever through each
gear range, pausing for about three seconds
in each range. Then,
position
the shift lever in “P’ (Park).
Let the engine run at idle for three minutes or more.
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When the engine
compartment is
hot, the level
should be at the
FULL mark.
When the engine
compartment
is
cool, the level
should be at the
FULL COLD
mark.
What to Add
Refer to the Maintenance Schedule to determine what kind of fluid to use.
See “Recommended Fluids and Lubricants”
in the Index.
NOTICE:
When adding power steering fluid or making a complete fluid
change, always use the proper fluid. Failure
to use the proper
fluid can cause leaks and damage hoses and seals.
Hydro-Boost Brake System (Hydraulic Pump)
The power steering pump is also used as the Hyrdo-boost pump. Refer to
“Power Steering System”
in this section when checking fluid level or
adding tluid.
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Brakes
Brake Master Cylinder
Your brake master
cylinder is here. It is
filled with
DOT-3
brake fluid.
There are only two reasons
why the brake fluid level in your master cylinder
might
go down, The first is that the brake fluid goes down to an acceptable
level during normal brake lining wear. When new linings are put in, the
fluid level goes back up. The other reason is that fluid is leaking
out of the
brake system.
If it is, you should have your brake system fixed, since a leak
means that sooner or later your brakes
won’t work well, or won’t work at
all.
So, it isn’t a good idea to “top off’ your brake fluid. Adding brake fluid
won’t correct a leak.
If you add fluid when your linings are worn, then
you’ll have
too much fluid when you get new brake linings. You should add
(or remove) brake fluid,
as necessary, only when work is done on the brake
hydraulic system.
Refer
to the Maintenance Schedule to determine when to check your brake
fluid. See “Periodic Maintenance Inspections”
in the Index.
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