Pontiac firebird 1968 - Bleeding Disc Brakes; Proportioning Valve Removal and Installation. 5 D-5; Torque Specifications 5 D-5

DISC BRAKES
5D-5
Fig. 5D-7 Checking Disc Runout
Disc thicknesses less than this can permit shoes to
come out of contact with shoe abutments and cause
malfunction. Because performance is not impaired
by surface imperfection not exceeding .015" deep,
refinishing of rubbing surface is not recommended.
PROPORTIONING VALVE—REMOVAL
AND INSTALLATION
1. Place dry rags below valve to absorb any fluid
spilled during removal of valve.
2. Disconnect hydraulic brake lines from both
sides of switch. Cover open lines with clean, lint-
free material to prevent foreign matter from enter-
ing the system.
3. Remove mounting screw and remove switch
from vehicle.
4. To install, reverse above procedure and bleed
brakes as outlined below.
BLEEDING DISC BRAKES
The bleeding operation for disc brakes is the same
as for drum brakes. The only exception Is that the
metering valve must be held open. This is done by
depressing and holding in the plunger in the end of
the valve either by hand or by tapping. Tool J 22793
may also be used to aid bleeding.
SPECIFICATIONS
Disc Brake Type ....... Fixed Caliper - Disc
Location Front Wheels Only
Disc Type .......... Ventilated - Cast Iron
Disc Diameter 11"
Disc Runout (Maximum) ........ .004" Total
Disc Surface Finish . 30-50 Micro-Inch
Disc Thickness, New .... Pontiac 1.250" - 1.260"
Firebird-Tempest .995" - 1.005"
Disc Thickness, Minimum ...... Pontiac 1.215"
Firebird-Tempest .965"
Disc Parallelism (Thickness Variation). . . .0005"
Brake Shoe and Lining Type ........ Riveted
Brake Shoe and Lining Thickness
(New) 495" - .505"
Brake Shoe and Lining Length ....... 5.950"
Brake Shoe and Lining Minimum
Thickness Before Replacement ....... .138"
Master Cylinder Diameter 1.125"
TORQUE SPECIFICATIONS
Torque
Size Application
120 lb. ft.
75 lb. ft.
60 lb. ft.
130 lb. ft.
65 lb. in.
5/8-18
1/2-20
7/16-14
9/16-18
Special
Bolt Splash Shield and Mounting Bracket to Knuckle (Upper)
Bolt & Nut Splash Shield and Mounting Bracket to Knuckle (Lower)
Bolt Caliper to Mounting Bracket
Bolt Caliper Assembly
Screw Caliper Bleeder