Steering control valves selectively pressurize and vent fluid-actuated clutches and brakes of a crawler tractor steering system. Each control valve has an internal spool assembly, coupled to a foot pedal by a cable, which modulates brake pressure as a function of a pedal position and which establishes a maximum brake fluid pressure thereby eliminating the need for additional system components for such purposes. The control valves also provide a feedback fluid pressure, to resist pedal depression with a force proportional to the brake fluid pressure, enabling an operator to sense the degree of braking which is present at different degrees of pedal depression.