Download 2004 Hummer H2 Brake Master Cylinder Service Manual – Removal Process ; 1. Apply the park brake and block the wheels. 2. Disconnect the electrical connector from the brake fluid degree sensor. IMPORTANT: Set up a rubber cap or plug to the exposed brake pipe fitting ends so as to forestall brake fluid loss and contamination. 3. Disconnect the brake pipes from the master cylinder.4. 5. 6. 7. Plug the open brake pipe ends. Take away the grasp cylinder mounting nuts. Take away the master cylinder from the vehicle. Remove the master cylinder reservoir. Installation Procedure1. Set up the grasp cylinder reservoir. 2. Bench bleed the grasp cylinder. Refer to Grasp Cylinder Bench Bleeding. 3. Install the master cylinder to the vehicle. NOTE: Check with Fastener Discover in Service Precautions.