1994 GMC SIERRA brake fluid

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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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 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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Explanation Of Scheduled Mainienance Services
Below are explanations of the services listed in the maintenance charts.
The proper fluids and lubricants to use are listed in this section. Make sure
whoever services your vehicle uses these. All parts should be replaced and
all necessary repairs done before you or anyone else drives the vehicle.
1. ENGINE OIL AND OIL FILTER CHANGE“‘ - ALWAYS USE
SJ3 ENERGY CONSERVING I1 (GASOLINE ENGINE) OR CF-4/SH
(DIESEL ENGINE) QUALITY OILS
OF THE PROPER VISCOSITY.
To determine the preferred viscosity oil for your vehicle’s engine (e.g.
SAE 5W-30 or 10W-30), see “Engine Oil”
in the Index.
2. CHASSIS LUBRICATION - Lubricate the front suspension, king
pin bushings, steering linkage, transmission, and transfer case shift
linkage, parking brake cable guides, rear driveline center splines and
front axle propshaft splines, brake pedal springs, and clutch pedal
springs at the intervals specified.
If you have a 3500
HD, lubricate the king pins and king pin bushings,
every
1,500 miles (2500 km) for Maintenance Schedule I, or every
3,000 (5000 km) for Maintenance Schedule 11.
Ball joints and king pin bushings should not be lubricated unless their
temperature
is 10” F (-12”C), or higher. When the weather is cold, let
them warm up before lubrication or
they could be damaged.
Also, be sure
to check all the vehicle fluid levels at this time.
3.
CLUTCH FORK BALL STUD LUBRICATION (5-SPEED
MANUAL TRANSMISSION WITH DEEP LOW
) - Lubricate the
clutch fork ball stud through the fitting
on the clutch housing.
Lubricant must be added “sparingly” to
the fitting, as only .0066 lb.
(.003 kg) is required to lubricate the ball stud surface. Do not add
lubricant more often than the intervals
in the Maintenance Charts. Too
much lubricant will damage the clutch assembly.
4. COOLING SYSTEM SERVICE”’? - Drain, flush and refill system
with new coolant. See “Engine Coolant” in the Index for
the proper
coolant and mixture to use
in your vehicle.
Also inspect the hoses and replace them
if they are cracked, swollen, or
deteriorated. Tighten all hose clamps (except constant tension clamps).
Remove debris and clean the outside of the radiator and air
conditioning condenser. Wash the radiator neck.
To ensure proper
operation, pressure test.
the radiator and cap.
* An Emission Control Service
?A fluid
loss in these systems may indicate a problem. Have them
inspected and repaired at once.
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5. AIR CLEANER FILTER REPLACEMENT* - Replace at every
30,000 miles (50 000 km) or more often under dusty conditions. Ask
your dealer for the proper replacement intervals for your driving
conditions.
6. FRONT WHEEL BEARING REPACK (2-WHEEL DRIVE
ONLY)
- Clean and repack the front wheel bearings at each brake
relining, or at
the specified interval, whichever comes first.
7. TRANSMISSION SERVICE’/-
Automatic Transmission
- Change the transmission fluid and filter
every
15,000 miles (25 000 km) for vehicles under 8,600 GVWR or
every 12,000 miles
(20 000 km) for vehicles over 8,600 GVWR if the
vehicle is mainly driven under one or more
of these conditions:
In heavy city traffic.
0 Where the outside temperature regularly reaches 90°F (32°C) or
0 In hilly or mountainous terrain.
higher.
Frequent
trailer pulling.
Uses such as taxi, police, delivery or other commercial service.
If the vehicle
is not used mainly under any of these conditions, change
the fluid and filter every
30,000 miles (50 000 km) for vehicles under
8,600
GVWR or every 24,000 miles (40 000 km) for vehicles over
8,600 GVWR see “Automatic Transmission Fluid”
in the Index for
more information.
Manual Transmission - Transmission fluid does not require periodic
changing.
8. CDRV SYSTEM INSPECTION* - Check the Crankcase
Depression Regulator Valve System for any worn, plugged or collapsed
hoses. Have the system checked as described in the Service Manual.
9. FUEL FILTER REPLACEMENT*$ - Replace the fuel filter at the
specified interval or sooner if clogged.
?A fluid loss
in these systems may indicate a problem. Have them
inspected and repaired at once.
:i: An Emission Control Service
$The California Air Resources Board bas determined that the failure to
perform this maintenance item will not
nullify the emission warranty or
limit recall liability prior to the completion
of the vehicle useful life.
General Motors, however, urges that all recommended maintenance
services be performed at the indicated intervals and the maintenance be
recorded.
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24. DRIVE AXLE SERVICE? - Check readfront axle fluid level and
add
as needed. Check constant velocity joints and axle seals for
leaking.
0
0
0
0
Locking differential - Drain fluid at first oil change and refill.
Check fluid level and add
as needed at subsequent oil changes. In
dusty areas, or trailer towing applications drain fluid at every
15,000 miles (24 135 kilometers) and refill.
Standard differential - Check fluid level and add as needed at
every
oil change. In dusty areas, or trailer towing applications,
drain fluid every
15,000 miles (24 I35 kilometers) and refill.
More frequent lubrication may be required on heavy-duty or
off-road use.
3500 HD Models - 3500 HD Models with applications requiring
extreme overload/trdiler tow conditions
and high speed conditions
(above 45 mph (72
kdh)) for extended periods of time must
change drive axle fluid every
3,000 miles (4828 kilometers) or 3
months, whichever comes first, OR must use 75W-140 synthetic
fluid meeting
GM specifications. See “Recommended Fluids and
Lubricants” at the end of this section for the proper fluid to use.
25.
BRAKE SYSTEM INSPECTION-f - When the engine oil is
changed, inspect the lines and hoses for proper hookup, binding, leaks,
cracks, chafing, etc. Check the parking brake adjust, and the fluid level
in the master cylinder. A low fluid level can indicate worn disc brake
pads which may need
to be serviced.
When the wheels are removed for rotation, inspect disc brake pads for
wear and rotors for surfxe condition. Also inspect drum brake linings
for wear and cracks. Inspect other brake parts, including drums, wheel
cylinders, parking brake, etc., at the same time. Remove any
rust or dirt
from the wheel and mounting surfaces before mounting the wheel.
Inspect brakes more often if driving habits or conditions result in
frequent braking.
?A fluid loss in these systems may indicate a problem. Have them
inspected and repaired at once.
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Owner Checks and Services
Listed below are owner checks and services which should be made at the
time period specified to help ensure proper safety, emission performance,
and dependability
of your vehicle.
Be sure any necessary repairs are completed at once. Whenever any fluids
or lubricants are added to your vehicle, make sure they are
the proper ones,
as shown
in this Section.
At Least Once a Month
Tire inflation pressure check - Check the tires for proper inflation. If
they are low, inflate them to the level specified on the Certification/Tire
label. See “Loading Your Vehicle” or “Inflation-Tire Pressure”
in the Index.
At Least Once a Year
Key lock cylinder lubrication - Lubricate key lock cylinders with engine
oil. See
the “Recommended Fluid and Lubricants” chart in this section.
Transmission neutral or clutch start switch operation -
1. Before you start, be sure you have enough room around the vehicle.
2. Firmly apply both the manual parking brake and the regular brake. See
“Brakes” and “Parking Brake”
in the Index. Do not use the accelerator
pedal.
3. Be ready to turn off the engine immediately if it starts.
4. On automatic transmission vehicles, try to start the engine in each gear.
The starter should work only
in “P’ (Park) or “N” (Neutral).
On manual transmission vehicles, put the shift lever
in “N” (Neutral), push
the clutch down halfway, and try to start the engine. The starter should work
only when the clutch
is pushed down all the way to the floor.
Steering column lock operation - While parked, try to turn the key to
LOCK in each gear shift position.
With an automatic transmission, the key should
turn to LOCK only when
the gear shift
is in “P” (Park).
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