Transmission having an electronically controlled main relief valve

A method of operating a transmission, comprising:

• pressurizing a fluid;
• directing the pressurized fluid through a manifold to a plurality of control valves fluidly communicating with the manifold in parallel relation;
• and
• electronically actuating a main pressure relief valve to selectively pass the pressurized fluid to a reservoir.

A work machine, comprising:

• a power source operable to generate a power output;
• a traction device;
• and
• a transmission configure to transmit the power output from the power source to the traction device, the transmission including:
• a reservoir configured to hold a supply of fluid;
• a source configured to pressurize the fluid;
• a manifold configured to receive the pressurized fluid;
• a plurality of control valves fluidly communicating with the manifold in parallel relation;
• a main pressure relief valve in fluid communication with the manifold and the reservoir, the main pressure relief valve having a valve element movable between a first position where fluid is allowed to flow from the manifold to the reservoir and a second position where fluid is blocked from flowing from the manifold to the reservoir;
• and
• a controller in communication the main pressure relief valve and configured to selectively move the valve element between the first and second positions, the controller being in further communication with each of the plurality of control valves and configured to selectively actuate the plurality of control valves in response to a predetermined condition.

A transmission comprising:

• a reservoir configured to hold a supply of fluid;
• a source configured to pressurize the fluid;
• a manifold configured to receive the pressurized fluid;
• a plurality of control valves fluidly communicating with the manifold in parallel relation;
• and
• a means for selectively passing pressurized fluid from the manifold to the reservoir.