1994 GMC SIERRA brake

To Check Brake Fluid
You can check the
brake fluid without
taking off the cap. Just
look at the windows
on the brake fluid
reservoir. The fluid
levels should be above
“MIN.” If they aren’t,
have your brake system checked to see
if there is a leak.
After work
is done on the brake hydraulic system, make sure the levels are
above
“MIN” and below the top of each window.
What to Add
When you do need brake fluid, use only DOT-3 brake fluid - such as
Delco Supreme
ll@ (GM Part No.1052535). Use new brake fluid from a
sealed container only, and always clean the brake fluid reservo\
ir cap before
removing it.
NOTICE:
Don’t let someone put in the wrong kind of fluid. For
example, just
a few drops of mineral-based oil, such as engine
oil, in your brake system can damage brake system parts so
badly that they’ll have to be replaced.
Brake fluid can damage paint, so be careful not to spill brake
fluid
on your vehicle. If you do, wash it off immediately. See
“Appearance Care” in the Index.
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Brake Wear
Your vehicle has front disc brakes and rear drum brakes. If you have a
C 3500 HD model, it has four-wheel disc brakes.
Disc brake pads have built-in wear indicators that make
a high-pitched
warning sound when the brake pads are worn and new pads are needed. The
sound may come and go or be heard
all the time your vehicle is moving
(except when you are pushing on the brake pedal firmly).
The brake wear warning sound means that sooner or later your
brakes won’t work well. That could lead to an accident.
When
you hear the brake wear warning sound, have your vehicle
serviced.
NOTICE:
Continuing to drive with worn-out brake pads could result in
costly brake repair.
Some driving conditions or climates may cause a brake squeal when the
brakes are first applied or lightly applied. This does not mean something is
wrong with your brakes.
If
you have rear drum brakes, they don’t have wear indicators, but if you
ever hear a rear brake rubbing noise, have
the rear brake linings inspected.
Also, the rear brake drums should be removed and inspected each time the
tires are removed for rotation or changing. When you have
the front brakes
replaced, have the rear brakes inspected, too.
Brake linings should always be replaced
as complete axle sets.
Brake Pedal Travel
See your dealer if the brake pedal does not return to normal height, or if
there is a rapid increase in pedal travel. This could be a sign of brake
trouble.
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Brake Adjustment
Every time you make a brake stop, your disc brakes adjust for wear.
If your brake pedal goes down farther than normal, your rear drum brakes
may need adjustment. Adjust them by backing up and firmly applying
the
brakes a few times.
Replacing Brake System Parts
The braking system on a modern vehicle is complex. Its many parts have to
be of top quality and work well together if the vehicle is to have really good
braking. Vehicles we design and test have top-quality
GM brake parts in
them, as your vehicle does when it is new. When you replace parts of your
braking system
- for example, when your brake linings wear down and
you have to have new ones put
in - be sure you get new genuine GM
replacement parts. If you don’t, your brakes may no longer work properly.
For example,
if someone puts in brake linings that are wrong for your
vehicle, the balance between your front and rear brakes can change, for
the
worse. The braking performance you’ve come to expect can change in many
other ways if someone puts in the wrong replacement brake parts.
Other Maintenance Hems
Front Suspension and Steering Linkage
Your maintenance schedule will tell you how often to lubricate the fittings.
See “Recommended Fluids and Lubricants”
in the Index for the proper
lubricant to use.
Front Wheel Bearings
Your vehicle has front wheel bearings that must be cleaned and repacked.
Your maintenance schedule
will tell you how often this must be done.
Front Shock Absorbers
The front shock absorbers of your vehicle do many things. They help the
vehicle ride smoothly and also control
the travel of the suspension system.
When the shock absorbers are serviced, any replacement shock absorbers
must be
the same as the original equipment shock absorbers in both
extended length and strength.
NOTICE:
If you use shock absorbers that are not the same as the original
shock absorbers, the shock absorbers
or suspension system
could be damaged.
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Trailer Wiring Harness
The optional seven-wire trailer wiring harness is protected by an in-line
fuse
in the battery feed wire. This fuse is near the junction block. See
“Trailer Wiring Harness”
in the Index for more information.
Fuse Block
The fuse block is
behind an access door
at the bottom of the
instrument panel,
next
to the parking brake
release lever.
To remove fuses if you don’t have one, hold the end of the fuse between
your thumb and index finger and pull straight out.
Be, sure to use the correct fuse.
If you ever have a problem on the road and
don’t have a spare fuse, you can “borrow” one of the correct value. Just pick
some feature
of your vehicle that you can get along without-like the radio
or cigarette lighter--and use
its fuse, if it is of the value you need. Replace
it as soon as you can. See “Fuses and Circuit Breakers“ in the Index for
more information.
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After you’ve loaded your vehicle and camper, drive to a weigh station and
weigh
on 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 CWAR and GVWR.
If
you’ve gone over your weight ratings, move or take out some things until
all the weights fall 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 hitch attached, so that you won’t go over the
GVWR or the 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.
Pickup Conversion To Chassis Cab
General Motors is aware that some vehicle owners may consider having the
pickup box removed and
a commercial or recreational body installed.
Before
you do so, first contact the GM Zone Office for your area for
information on such conversions. (See the “Warranty and Owner
Assistance” booklet for Zone Office.) Owners should be aware that, as
manufactured, there are differences between a chassis cab and a pickup with
the box removed which may affect vehicle safety. The components
necessary to adapt
the pickup to permit its safe use with a specialized body
should be installed by a body builder
in accordance with the information
available from
the Zone Office.
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NOTICE:
The wrong wheel can also cause problems with bearing life,
brake cooling, speedometer/odometer calibration, headlight aim,
bumper height, vehicle ground clearance, and tire or tire chain
clearance to the body and chassis.
Used Replacement Wheels
Tire Chains
NOTICE:
If your vehicle has dual wheels or LT26Y75R16 size tires, don’t
use tire chains; they can damage your vehicle.
If you don’t have
dual wheels or
if you have a tire size other than LT265/75R16,
use tire chains only where legal and only when you must. Use
only SAE Class “S” type chains that are the proper size for your
tires. Install them on the tires of the rear axle. Tighten them as
tightly
as possible with the ends securely fastened. Drive slowly
and follow the chain manufacturer’s instructions.
If you can
hear the chains contacting your vehicle, stop and retighten them.
If the contact continues, slow down until it stops. Driving too
fast with chains on will damage your vehicle.
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Fuses and Circuit Breakers
NAME CIRCUITS PROTECTED
Gages
Turn-B/U EMC/Ign
Ign. A
Brake
AC/Htr
Ctsy
Park LP
P. Lps
Stop/Haz.
Wiper
Radio
Acc/Ign.
Acc/Batt.
Crank
4WD
DRL
Cruise Control, 4 WD Display
Illum. Rear Window Defogger
Timer, Aux. Batt. Relay Feed,
Safety Belt Buzzer Timer, Cluster
Ign. Feed
Back-up Lamps,
Turn Signals
T.C.C., Air Diverter,
E.S.C.,
E.G.R., E.C.M. Ign., R.W.A.L.
Brake Switch
Throttle Body Injectors
R.W.A.L., Cluster-Speedo
H.V.A.C.
4WD, Aux. Batt. Relay
Dome Lamp, Cargo Lamp, Ctsy,
and Glove Box Lps. (TR-R), Radio
(Memory-Clock) Horn Relay, Horn
Feed, Cigar Lighter, Park
Lamps C49 SW Illum., Headlamp “On”
Warning,
Radio Illum., H.V.A.C. Illum. Haz.
Flasher, Seat Belt Buzzer, Stop
Lmps., R.W.A.L. Memory
Windshield Wiper, Washer
Radio Feed
Pwr. Windows
Door Locks, Rear Window
Defogger
Crank, Discreet
Four Wheel Drive
Daytime Running Lights
FUSE CIRCUIT
BREAKER
20 Amp
15 Amp
10 Amp
10 Amp
15 Amp
25 Amp
20 Amp
20 Amp
5 Amp
15 Amp
25 Amp
10 Amp
30 Amp
30 Amp
5 Amp
25 Amp
15 Amp
*An inline fuse is used
for the underhood lamp
Do not use fuses of higher amperage than those recommended above.
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Heater or A/C Control Lamp
Four Wheel Drive Indicator
rour Wheel Drive Shift Lever
Instrument Panel Compartment Lamp
Ashtray Lamp
Sunshade Vanity Mirror
"Crew Cab Only
LAMP OR BULB
INSTRUMENT PANEL
Transmission Indicator (PRNDL)
Daytime Running Lights Indicatory
Charging System Indicator Lamp
Instrument Cluster Illumination
--Gage Cluster
Instrument Cluster Illumination
-Tachometer Cluster
Headlamp Beam Indicator
Directional Signal Indicator
Brake Warning Indicator
Safety Belt Warning
Check Gages Indicator
Malfunction Indicator ("Service
Engine Soon") Lamp
Upshift Indicator
Glow Plugs Lamp*:$:
Low Coolant
Water
in Fuel Lamp*'$
Service Throttle Soon Lamp*"
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