G 2500 3/4 Ton Van V6-262 4.3L VIN Z (1992)
Brake Bleeding: Technical Service Bulletins
Brakes - Revised Bleeding Procedure
GMC NO.: 93-U-001
BOOK NO.:
SECTION: 5E1
CORP. NO.: 263003
DATE: September 1992
SUBJECT:
REVISED 4WAL BLEEDING PROCEDURE
MODELS:
ALL 1990-1993 LIGHT DUTY TRUCKS WITH 4WAL
BLEEDING THE BPMV
The 4WAL brake pressure modulator valve (BPMV) should be bled after replacement or if air is trapped in it. Bleeding should not be necessary if the
fluid is not contaminated or no air is in the BPMV. There are internal bleed valves on each side of the BPMV that open internal channels. Open the
internal bleed valves (item A, figure 1) 1/4 to 1/2 turn before bleeding. Should the module need bleeding, it must be bled after the master cylinder and
before the wheel cylinders and calipers.
NOTICE:
The ignition switch must be in the "OFF" position or false trouble codes could be set to memory.
Tools Required:
J 39177 Combination Valve Pressure Bleeding Tool (Three required)
TK 00000 Tech-1 Scan Tool
TK 02650 RWAL/4WAL Cartridge Kit or
3000003 Mass Storage Cartridge
You can also use a modified J 35856 Combination Valve Pressure Bleeding Tool providing you remove the dimple from it first.
Important
You can expect to use two quarts of brake fluid to thoroughly bleed the system.
1.
Open the internal bleed valves on the sides of the BPMV 1/4 to 1/2 turn each (A).