Brake Master Cylinder - Service and Repair - Bleeding
cracked to release any air and then retightened.
NOTE: All vehicles are equipped with a pressure hold-off valve. The valve is located (in the combination valve) on the left frame rail. The hold off
valve balances front and rear braking force to improve braking and steering control on icy surfaces. The valve shuts off the flow of brake fluid between 3
and 135 PSI. Because the valve shuts off flow in this pressure range the valve must be held open manually -- using tool C-4121 or equivalent -- when
pressure bleeding the system. Gravity and pedal bleeding DO NOT require holding this valve open.
