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A valve assembly includes a valve housing defining a service passage, a first bore in fluid communication with the service passage, a first passage, a second bore in communication with the service passage and a second passage. The first bore has an inlet portion, a first service portion in communica

A valve assembly includes a valve housing defining a service passage, a first bore in fluid communication with the service passage, a first passage, a second bore in communication with the service passage and a second passage. The first bore has an inlet portion, a first service portion in communication with the service passage, and a first load holding portion. The first passage is in communication with the first load holding portion and the service passage. The second bore has a return portion, a second service portion in fluid communication with the first service passage, and a second load holding portion. The second passage is in selective communication with the second load holding portion of the second bore and the return passage. A valve is disposed in the second passage. The valve allows fluid to flow only in a direction from the second load holding portion to the return passage.

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1. A valve assembly comprising: a valve housing defining: a first service passage;a first valve bore in fluid communication with the first service passage, the first valve bore having an inlet portion in fluid communication with an inlet passage of the valve housing, a first service portion in fluid

1. A valve assembly comprising: a valve housing defining: a first service passage;a first valve bore in fluid communication with the first service passage, the first valve bore having an inlet portion in fluid communication with an inlet passage of the valve housing, a first service portion in fluid communication with the first service passage, and a first load holding portion, the first valve bore having a first valve seat that is disposed between the inlet portion and the service portion;a first fluid passage in selective fluid communication with the first load holding portion of the first valve bore and the first service passage;a second valve bore in fluid communication with the first service passage, the second valve bore having a return portion in fluid communication with a return passage of the valve housing, a second service portion in fluid communication with the first service passage, and a second load holding portion, the second valve bore having a second valve seat that is disposed between the return passage and the first service passage;a second fluid passage in selective communication with the second load holding portion of the second valve bore and the return passage;an inlet valve disposed in the first valve bore, the inlet valve being moveable between a seated position and an unseated position;a return valve assembly disposed in the second valve bore, the return valve being moveable between a seated position and an unseated position; anda one-way valve disposed in the second fluid passage, wherein the one-way valve allows fluid to flow only in a direction from the second load holding portion to the return passage. 2. The valve assembly of claim 1, wherein the inlet valve includes a body defining a first metering passage through the body, the first metering passage being in fluid communication with the inlet passage and the first load holding portion of the first valve bore. 3. The valve assembly of claim 2, wherein a check valve is disposed in the first metering passage, the check valve providing fluid flow only in a direction from the inlet passage to the first load holding cavity. 4. The valve assembly of claim 2, wherein the return valve defines a second metering passage providing fluid communication between the second load holding portion and the second service portion of the second valve bore. 5. The valve assembly of claim 4, wherein the inlet valve includes a circumferential surface defining a first metering slot, the first metering slot being in fluid communication with the first metering passage. 6. The valve assembly of claim 5, wherein the return valve includes a circumferential surface defining a second metering slot, the second metering slot being in fluid communication with the second metering passage. 7. The valve assembly of claim 1, wherein the first valve seat is frusto-conical in shape. 8. The valve assembly of claim 1, wherein the one-way valve is a check ball. 9. A valve assembly comprising: a valve housing defining: a first service passage;a first valve bore in fluid communication with the first service passage, the first valve bore having an inlet portion in fluid communication with an inlet passage of the valve housing, a first service portion in fluid communication with the first service passage, and a first load holding portion, the first valve bore having a first valve seat that is disposed between the inlet portion and the service portion;a first fluid passage in selective fluid communication with the first load holding portion of the first valve bore and the first service passage;a second valve bore in fluid communication with the first service passage, the second valve bore having a return portion in fluid communication with a return passage of the valve housing, a second service portion in fluid communication with the first service passage, and a second load holding portion, the second valve bore having a second valve seat that is disposed between the return passage and the first service passage;a second fluid passage in selective communication with the second load holding portion of the second valve bore and the return passage;an inlet valve disposed in the first valve bore, the inlet valve including a body defining a first metering passage through the body, the first metering passage being in fluid communication with the inlet passage and the first load holding portion of the first valve bore, the inlet valve further including a check valve disposed in the first metering passage, the check valve providing fluid flow only in a direction from the inlet passage to the first load holding cavity;a return valve assembly disposed in the second valve bore, the return valve defining a second metering passage that provides fluid communication between the second load holding portion and the second service portion of the second valve bore; anda one-way valve disposed in the second fluid passage, wherein the one-way valve allows fluid to flow only in a direction from the second load holding portion to the return passage. 10. The valve assembly of claim 9, wherein the inlet valve includes a circumferential surface defining a first metering slot, the first metering slot being in fluid communication with the first metering passage. 11. The valve assembly of claim 10, wherein the return valve includes a circumferential surface defining a second metering slot, the second metering slot being in fluid communication with the second metering passage. 12. The valve assembly of claim 9, wherein the first valve seat is frusto-conical in shape. 13. The valve assembly of claim 9, wherein the one-way valve is a check ball. 14. The valve assembly of claim 9, further comprising a middle stage valve assembly in fluid communication with the inlet valve and the return valve, the middle stage valve assembly being adapted to provide fluid communication between the first load holding portion of the first valve bore and the first fluid passage and between the second load holding portion of the second valve bore and the second fluid passage. 15. The valve assembly of claim 14, wherein the middle stage valve assembly is a four-way, three-position proportional valve. 16. A valve assembly comprising: a pilot stage valve assembly;a middle stage valve assembly in fluid communication with the pilot stage valve assembly;a main stage valve assembly in fluid communication with the middle stage valve assembly, the main stage valve assembly including: a valve housing defining: a first service passage;a first valve bore in fluid communication with the first service passage, the first valve bore having an inlet portion in fluid communication with an inlet passage of the valve housing, a first service portion in fluid communication with the first service passage, and a first load holding portion, the first valve bore having a first valve seat that is disposed between the inlet portion and the service portion;a first fluid passage in selective fluid communication with the first load holding portion of the first valve bore and the first service passage;a second valve bore in fluid communication with the first service passage, the second valve bore having a return portion in fluid communication with a return passage of the valve housing, a second service portion in fluid communication with the first service passage, and a second load holding portion, the second valve bore having a second valve seat that is disposed between the return passage and the first service passage;a second fluid passage in selective communication with the second load holding portion of the second valve bore and the return passage;an inlet valve disposed in the first valve bore, the inlet valve including a body defining a first metering passage through the body, the first metering passage being in fluid communication with the inlet passage and the first load holding portion of the first valve bore, the inlet valve further including a check valve disposed in the first metering passage, the check valve providing fluid flow only in a direction from the inlet passage to the first load holding cavity;a return valve assembly disposed in the second valve bore, the return valve defining a second metering passage that provides fluid communication between the second load holding portion and the second service portion of the second valve bore; anda one-way valve disposed in the second fluid passage, wherein the one-way valve allows fluid to flow only in a direction from the second load holding portion to the return passage. 17. The valve assembly of claim 16, wherein the pilot stage valve assembly includes an electronic actuator. 18. The valve assembly of claim 17, wherein the electronic actuator is a voice coil. 19. The valve assembly of claim 16, wherein pilot stage valve assembly provides fluid to at least one end of a middle stage spool valve of the middle stage valve assembly to actuate the middle stage valve assembly. 20. The valve assembly of claim 16, wherein the middle stage valve assembly is a four-way, three-position proportional valve.