Combination Valve: Removal

Using Tech 1 scan tester, perform gear tension release procedure. See Tech 1 scan tester instructions for more information. Remove air cleaner duct assembly. Disconnect electrical connectors from ABS modulator solenoids, brake pressure differential switch on combination valve and ABS modulator motor pack. See Fig 1 .

Fig 1: Exploded View Of ABS Modulator
Courtesy of GENERAL MOTORS CORP.
Place shop cloth on top of motor pack to catch dripping brake fluid. Disconnect brakelines from combination valve and ABS modulator. Plug openings. DO NOT allow brake fluid to enter bottom of motor pack or electrical connectors. Remove bolt securing front of ABS modulator to frame rail.
Remove ABS modulator. Remove 2 Torx head screws securing gear cover to bottom of ABS modulator. Remove gear cover. Remove 4 Torx head screws securing motor pack to ABS modulator. Remove motor pack.
Remove 2 banjo bolts securing ABS modulator to combination valve. Separate ABS modulator from combination valve. Remove 2 transfer tubes installed between ABS modulator and combination valve. Remove banjo bolt "O" rings from ABS modulator and combination valve.