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A transaxle for use as a drive apparatus of a vehicle is provided. The transaxle includes a main housing joined to a gear housing to enclose a transmission and a reduction gear set. The transmission includes a pump assembly and a motor assembly arranged in a parallel configuration on one side of a c

A transaxle for use as a drive apparatus of a vehicle is provided. The transaxle includes a main housing joined to a gear housing to enclose a transmission and a reduction gear set. The transmission includes a pump assembly and a motor assembly arranged in a parallel configuration on one side of a center section. A charge pump is contained within a pocket on an opposing side of the center section. A charge pump cover assembly secures the charge pump in the pocket and has a charge relief assembly that extends into a void volume defined by a ring gear of the gear reduction set. The gear reduction set drives an axle extending from the gear housing.

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1. A drive apparatus comprising: a housing forming a sump;a center section disposed in the sump and having a first side and a second side opposite the first side, the center section further comprising a pump running surface formed on the first side;a pump disposed on the pump running surface and dri

1. A drive apparatus comprising: a housing forming a sump;a center section disposed in the sump and having a first side and a second side opposite the first side, the center section further comprising a pump running surface formed on the first side;a pump disposed on the pump running surface and driven by a pump input shaft;a charge pump disposed on the second side of the center section and driven by the pump input shaft;a charge pump cover disposed on the second side of the center section, said charge pump cover having an external surface, an internal surface defining a charge gallery and a charge relief passage through said charge pump cover; anda charge relief assembly extending from the external surface of the charge pump cover and communicating with the charge relief passage. 2. The drive apparatus of claim 1, further comprising a pocket formed on the second side of the center section, wherein the charge pump is disposed in the pocket and the charge pump cover is disposed over the pocket. 3. The drive apparatus of claim 1, further comprising a charge relief tower formed on and extending from the external surface of the charge pump cover. 4. The drive apparatus of claim 1, further comprising a motor disposed in the sump and engaged to and driving a motor output shaft. 5. The drive apparatus of claim 4, further comprising an axle extending into the housing and driven by the motor output shaft, and a second pocket formed in the second side of the center section to support an end of the axle. 6. The drive apparatus of claim 4, wherein the motor is an axial piston motor and the pump is an axial piston pump. 7. The drive apparatus of claim 4, wherein the motor output shaft has a first axis of rotation that is parallel to a second axis of rotation of the pump input shaft, and wherein the charge gallery comprises two internal volumes disposed between the charge pump cover and the second side of the center section, and a center passage extending between the two internal volumes, wherein the center passage extends in a direction that is generally perpendicular to a plane formed by the first and second axes of rotation. 8. The drive apparatus of claim 7, further comprising hydraulic porting formed in the center section, and a first check valve and a second check valve extending into the center section from the second side thereof to permit hydraulic fluid to enter the hydraulic porting, wherein the first check valve is disposed adjacent one of the two internal volumes and the second check valve is disposed adjacent the other of the two internal volumes. 9. The drive apparatus of claim 8, wherein the charge relief passage is disposed in the center passage. 10. The drive apparatus of claim 9, wherein the charge pump cover further comprises a charge pump inlet extending through the charge pump cover to permit hydraulic fluid to flow from the sump to the charge pump. 11. The drive apparatus of claim 10, wherein the charge pump cover further comprises a clearance pocket to allow clearance of the pump input shaft with respect to the charge pump cover, and the charge pump inlet is disposed on one side of the clearance pocket and the center passage is disposed on a second side of the clearance pocket opposite the first side. 12. A drive apparatus comprising: a housing forming a sump;a center section disposed in the sump and comprising a pump running surface and a motor running surface;hydraulic porting formed in the center section;a pump rotatably disposed on the pump running surface and driven by a pump input shaft having a first axis of rotation;a motor rotatably disposed on the motor running surface and driving a motor shaft having a second axis of rotation that is parallel to the first axis of rotation, wherein the motor is in communication with the pump through the hydraulic porting;a charge pump disposed on the center section and driven by the pump input shaft;a charge pump cover disposed on the center section and having an external surface, an internal surface defining a charge gallery and a charge relief passage through said charge pump cover;a charge relief assembly extending from the external surface of the charge pump cover and communicating with the charge relief passage;wherein the charge gallery comprises two internal volumes disposed between the charge pump cover and the center section, and a center passage extending between the two internal volumes, wherein the center passage extends in a direction that is generally perpendicular to a first plane formed by the first and second axes of rotation. 13. The drive apparatus of claim 12, further comprising a first check valve and a second check valve extending into the center section to permit hydraulic fluid to enter the porting, wherein the first check valve is disposed adjacent one of the two internal volumes and the second check valve is disposed adjacent the other of the two internal volumes. 14. The drive apparatus of claim 13, wherein a second plane, perpendicular to the first plane, passes through the first check valve, the second check valve and the charge pump. 15. The drive apparatus of claim 14, wherein the first axis of rotation and the second axis of rotation lie on a third plane that is parallel to the second plane. 16. The drive apparatus of claim 12, further comprising a reduction gear set disposed in the housing and driven by the motor shaft, and an axle shaft extending into the housing and having a third axis of rotation, the axle shaft being driven by the reduction gear set. 17. The drive apparatus of claim 16, wherein the center section further comprises a first opening to support the pump input shaft, a second opening to support the motor shaft and a third opening to support the axle shaft. 18. The drive apparatus of claim 17, wherein the third axis of rotation is parallel to the first and second axes of rotation and the third axis of rotation lies on a common plane. 19. A drive apparatus comprising: a housing forming a sump;a charge pump mounting surface located in the sump;a charge pump disposed on the charge pump mounting surface and in communication with a hydraulic porting system;a charge pump cover disposed on the charge pump mounting surface, said charge pump cover having an external surface, an internal surface defining a charge gallery and a charge relief passage through said charge pump cover; anda charge relief assembly extending from the external surface of the charge pump cover and communicating with the charge relief passage to permit hydraulic fluid to be discharged from the charge gallery to the sump. 20. The drive apparatus of claim 19, further comprising a charge relief tower formed on and extending from the external surface of the charge pump cover, wherein the charge relief tower forms a part of the charge relief assembly.