V 20 P/U 4WD V8-379 6.2L DSL (1988)
Vacuum Brake Booster: Testing and Inspection
Brakes Grab
1.
Faulty control valve.
2.
Broken or damaged hydraulic brake lines.
3.
Faulty master cylinder seals.
4.
Cracked master cylinder casting.
5.
Air in hydraulic system.