1993 GMC SIERRA brake fluid

Brake Master Cylinder
Your brake master cylinder is here. It is filled with DOT-3 brake fluid.
K2470
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.
CAUTION I
If you have too much brake fluid, it can spill on the engine. The fluid
and your vehicle could be damaged. Add
. ake fhid nnlv en wn
is done on the brake hydraulic system.
- will burn if the engine is hot enough. You or others could he burned
Refer
to the Maintenance Schedule to determine when to check your brake
fluid. See “Periodic Maintenance” in the index.
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 the
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Service & Appearance Care
MIN mark. If they aren’t, have your brake system checked to see if there is a
leak.
t
After work is done on the brake hydraulic system, make sure t\
he 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
11 @ (GM Part No. 1052535). Use new brake fluid from a sealed
container only.
Hydro-Boost Brake System (Hydraulic Pump)
The power steering pump is also used as the Hydro-boost pump. Refer to
“Power Steering System” in this section when checking fluid level or adding
fluid.
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.
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Scheduled Maintenance Services
Explanation Of Scheduled Maintenance 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 ve\
hicle.
1.
ENGINE OIL AND OIL FILTER CHANGE* -ALWAYS USE SG OR
SGKE QUALITY, ENERGY CONSERVING II 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, propshaft splines (2 wheel drive), 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 1, or every 3,000
(5000 km) for Maintenance Schedule 2.
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 -Lubricate the clutch fork
ball stud through the fitting on the clutch housing. Lubricant must be
added “sparingly” to the fitting, as only.
0066 Ib. (.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. ENGINE IDLE SPEED ADJUSTMENT (DIESEL ENGINES)* -Adjust to
the specifications shown on the underhood label. You must use
calibrated test equipment.
5. 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
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6. 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\
.
7. 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.
8.
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.
Where the outside temperature regularly reaches 90°F (32°C\
) or
higher.
In hilly or mountainous terrain.
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
8600 GVWR or every
24,000 miles (40 000 km) for vehicles over 8600
GVWR. See “Automatic Transmission Fluid” in the Index for more
information.
Manual Transmission -Transmission fluid does not require periodic
changing.
Regulator Valve System for any worn, plugged or collapsed hoses. Have
the system checked as described in the Service Manual.
9.
CDRV SYSTEM INSPECTION* -Check
the Crankcase Depression
10. FUEL FILTER REPLACEMENT* -Replace the fuel filter at the specified
interval
or sooner if clogged.
11. SPARK PLUGS REPLACEMENT* -Replace spark plugs with the type
listed in Section
6. See “Specification Charts” in the Index.
12.
SPARK PLUG WIRE INSPECTION* -Clean wires and inspect for burns,
cracks or other damage. Check the wire boot fit at the distributor and at
the spark plugs. Replace wires as needed.
*An Emission Control Service
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23. EXHAUST PRESSURE REGULATOR VALVE INSPECTION* -Check that
the valve works properly. Correct any binding. Inspect hoses fo\
r cracks, chafing or decay. Replace parts as needed.
24.
TIRE AND WHEEL ROTATION AND INSPECTION -For proper wear
and maximum tire life, rotate tires at the first
6,000 miles (1 0 000
kilometers) for Schedule I (t) or 7,500 miles (12 500 kilometers) for
Schedule
II (.) and then every 15,000 miles (25 000 kilometers)
thereafter. Follow the instructions and patterns shown in Section 6.
Check tires for uneven wear or damage.
If irregular or premature wear is
apparent, check wheel alignment. Also, check for damaged wheels.\
See
“Tires” in the Index for more information.
For dual wheels, whenever the vehicle, wheels, or fasteners are new,
have the wheel fastener torque set at the first 100,
1,000 and 6,000
miles (160, 1600 and 10
000 km).
For 3500 H.D. Models, block the tires opposite those being removed to
keep the vehicle from rolling.
25.
DRIVE AXLE SERVICE -Check readfront axle fluid level and add as
needed. Check constant velocity joints and axle seals for leaki\
ng.
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 15,0\
00 miles
(24 135 kilometers) and refill$
every oil change. In dusty areas, or trailer towing applications, drain
fluid every 15,000 miles
(24 135 kilometers) and refi1l.t
More frequent lubrication may be required on heavy-duty or off-road
use.
Standard differential -Check fluid level and add as needed at
26.
BRAKE SYSTEM INSPECTION -When the engine oil is changed,
inspect the lines and hoses for proper hookup, binding, leaks, \
cracks,
chafing, etc. Check the parking brake adjustment, and the fluid level in
the master cylinder.
A low fluid level can indicate worn disc brake pads
which may need to be sewiced.t
*An Emission Control Service
tA fluid
loss in these systems may indicate a problem. Have them
inspected and repaired at once.
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Scheduled Maintenance Sewices
When the wheels are removed for rotation, inspect disc brake pads f\
or wear
and rotors for surface condition.
Also inspect drum brake linings for wear and
cracks. Inspect other brake parts, including drums, wheel cylind\
ers, 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 resull In
frequent braking.
Owner Checks and Services
Listed below are owner checks and services which should be mad\
e 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 label or on the
tire inflation charts. 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
CAUTION
~
1. Before you start, be sure you have enough room around the veh\
icle.
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).
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Recommended Fluids & Lubricants
NOTE: Fluids and lubricants identified below by name, part number or
specification may be obtained from your
GM Dealer.
USAGE I FLUID/LUBRICANT
Engine Oil
I
GM Goodwrench Motor Oil or equivalent for API Service SG
or SGlCE of the recommended viscositv.
Engine Coolant Mixture
of water and a good quality ethylene glycol base
antifreeze conforming
to GM-6038-M (GM Part No. 1052103).
Hydraulic Clutch System Hydraulic Clutch Fluid (GM Part
No. 12345347 or equivalent).
Hydraulic Brake Systems Delco Supreme
11
@ brake fluid (GM Part No. 1052535 or
DOT-3).
Parking Brake Cables
GM Lubricant (GM Part
No. 1052182) or equivalent.
Manual Steering Gear GM Power Steering
Fluid (GM Part
No. 1050017) or
Power Steering System Chassis grease meeting requirements of
NLGl Grade 2,
Automatic Transmission DEXRONB
HE Automatic Transmission Fluid (GM Part
No.
Catagory LB or GC-LB (GM Part No. 1052497).
equivalent conforming
to GM spec 9985010.
1051
855l.
Manual Transmission:
a. 5-Speed with Low Gear
b. Standard Transmission Fluid (GM Part
No. 12345349).
b. 5-Speed without Low Gear a.
CastrolB Syntorq or equivalent (GM Part
No.
1 2346074).
Differential:
a. Standard (Saginaw) Front
b. SAE-80W-90 gear lubricant (GM Part No. 1052271). b. Locking a.
SAE-80W-90 gear lubricant (GM Part
No. 1052271).
and Rear Axle
Transfer Case Gas Line De-lcer (GM Part
No. 1051516).
Gas Line DexronB
IIE Automatic Transmission
Fluid (GM Part No.
12345881).
Weather Strips
Category LB or GC-LB (GM Part
No. 1052497).
Chassis grease meeting requirements
of NLGl
Grade 2,
Clutch Fork Ball Stud Category
LB or GC-LB (GM Part
No. 1052497).
Shift Lever, and Propeller Shaft. Chassis grease meeting requirements
of NLGl Grade 2,
Column Shift, Transfer Case Spray-A-Squeek
(GM Part
No. 1052277).
(Continued next
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A
B
Battery ........................................... 6-54
Belts (See "Safety Belts")
Better Business Bureau Mediation 8-3
Bliizard
.......................................... 4-54
Brakes 'Adjustment
................................. 4-19
Antilock
...................................... 4-16
Fluid
........................................... . 6.49
Leak Check
............................... 6-52
Master Cylinder ........................ 6-49
Parking
....................................... 2-29
Pedal Travel
.............................. 4-19
Rear Drum
..... ; .......................... 4-19
Replacing Parts
........................ 6-50
System Warning Light .2.79, 4-18
Trailer
......................................... 4-58
Wear Indicators
........................ 4-18
Braking
....................................... .'.'4.14
In Emergencies
........................ 4-19
Break.ln, New Vehicle
; ................ 2.10
Bulb Replacement ............. 6.54, 6-98
Replacement Chart
.................. 6-98
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