Brake release system

A work vehicle comprising;

• a frame;
• ground engaging means for supporting and propelling the frame;
• a dual path hydrostatic transmission for driving the ground engaging means, the dual path hydrostatic transmission having left and right variable displacement pumps having an output;
• a charge pump for the left and right variable displacement pumps;
• spring applied hydraulically released brakes for braking the ground engaging means;
• a controller for controlling the output of the left and right variable displacement pumps and the application of the spring applied hydraulically released brakes, a manual control element that is operated by an operator signals the controller when to apply the spring applied hydraulically released brakes;
• a brake system hydraulic line extends from the charge pump to the spring applied hydraulically released brakes for directing pressurized hydraulic fluid from the charge pump to the spring applied hydraulically released brakes;
• a secondary hydraulic system for performing a secondary operation having a manually operated hydraulic pump that provides pressurized hydraulic fluid to a hydraulic cylinder for a secondary vehicle operation through a secondary system hydraulic line;
• wherein the secondary system hydraulic line is provided with a first hydraulic quick coupler and a second hydraulic quick coupler which are coupled together when the secondary system is being operated, the brake system hydraulic line is provided with a third hydraulic quick coupler that is coupled to the first hydraulic quick coupler when the work vehicle is being towed so that the manually operated hydraulic pump supplies pressurized hydraulic fluid to the spring applied hydraulically released brakes to release the spring applied hydraulically released brakes.