Chevrolet LIGHT DUTY TRUCK (SERIES 10-35) Service Manual page 392

assembly procedure of components in this portion of the manual as
indicated at appropriate locations by the terminology "See Caution on
page
grinding or sanding brake linings or by cleaning wheel brake parts with
a dry brush or with compressed air. (A water dampened cloth should
be used.) Many wheel brake parts contain asbestos fibers which can
become airborne if dust is created during servicing. Breathing dust
containing asbestos fibers may cause serious bodily harm."
could affect the performance of vital components and systems, and/or
could result in major repair expense. It must be replaced with one of the
same part number or with an equivalent part if replacement becomes
necessary. Do not use a replacement part of lesser quality or substitute
design. Torque values must be used as specified during reassembly to
assure proper retention of this part.
General Description........................................................5 - 1
Diagnosis...................................................................... ..5-2
On-Vehicle Service....................................................... ..5-10
Pedal Travel............................................................. ..5-10
Stop Light Switch.................................................... ..5-10
Bleeding and Flushing Brakes....................................5-10
Hydro-Boost Bleeding Procedure...............................5-11
Brake Pipes............................................................... ..5-11
Brake Hoses............................................................. ..5-11
Parking Brake Pedal or Handle.................................5-16
Parking Brake Adjustment.........................................5-16
Parking Brake (Propshaft) Internal Expanding........5-20
Parking Brake Cable...................................................5-23
Combination Value.....................................................5-23
Brake Pedal.............................................................. ..5-23
Brake Pedal Rod...................................................... ..5-24
Master Cylinder....................................................... ..5-25
Delco Disc Brake Shoe and Lining...........................5-27
All vehicles are equipped with a dual hydraulic brake
system.
The split system consists basically of two separate
brake systems. When a failure is encountered on either, the
other is adequate to stop the vehicle. If one system is not
functioning, it is normal for the brake pedal lash and pedal
effort to substantially increase. This occurs because of the
design of the master cylinder which incorporates an
actuating piston for each system. When the rear system loses
fluid, its piston will bottom against the front piston. When
the front system loses fluid, its piston will bottom on the
SECTION 5
B R A K E S
The following caution notes apply to one or more steps in the
1 of this section".
When servicing wheel brake parts, do not create dust by
Caution:
This fastener is an important attaching part in that it
CAUTION:
CONTENTS
GENERAL DESCRIPTION
Bendix Disc Brake Shoe and Lining........................ 5-32
Caliper Overhaul...................................................... 5-33
Rotor Servicing........................................................ 5-36
Brake Drum Shoe and Lining.................................. 5-37
Standard Drum Brake......................................... 5-37
Propeller Shaft Brake........................................... 5-39
Brake Drums............................................................ 5-40
Wheel Cylinder........................................................ 5-41
Power Brake U nit................................................. .
Vacuum Booster................................................... 541
Hydro-Boost U n it................................................ 543
Specifications.................................................. ...... ...... 5-47
Brake System Description....................................... 547
Brake System Application.......................................
Torque Specifications............................................... 5-52
Special Tools................................................................ 5-53
end of the master cylinder body. The pressure differential
in one of the systems causes an uneven hydraulic pressure
balance between the front
combination valve (near the master cylinder) detects the loss
of pressure and illuminates the brake alarm indicator light
on the instrument panel. The pressure loss is felt at the brake
pedal by an apparent lack of brakes for most of the brake
travel and then, when failed chamber is bottomed, the pedal
will harden.
If a vehicle displays these symptoms, it is a good
indication that one of the systems contains air or has failed,
BRAKES 5-1
5-41
547
and rear systems. The
LIG H T T R U C K S ER V IC E MANUAL