Patent ID: 8452504

Claim:
A drivetrain for a vehicle comprising: a multi-ratio transmission; a two-speed final drive assembly connected in series with the multi-ratio transmission and including a low speed final drive ratio and a high speed final drive ratio; a pair of front driveshafts driven by the two-speed final drive assembly; a pair of rear driveshafts; a rear differential assembly connected to the two-speed final drive assembly and including, a high capacity mode and a low capacity mode, an input member driven by the two-speed final drive assembly, first and second clutch assemblies selectively coupling the input member to a respective one of the pair of rear driveshafts, each of the clutch assemblies including, a plurality of driven plates connected to the input member, and a plurality of driving plates selectively engageable with the plurality of driven plates, first and second pistons each associated with a respective one of the first and second clutch assemblies, each of the first and second pistons configured to displace the plurality of driving plates into engagement with the plurality of driven plates, a variable displacement pump, and a purge valve, wherein the purge valve and at least one of the first and second pistons are in parallel fluid communication with the variable displacement pump; and a control assembly including, a controller in electrical communication with the variable displacement pump and the purge valve, and an input array in electrical communication with the controller and including, a plurality of sensors, and at least one switch accessible to an operator of the vehicle.