Abstract: A method for estimating a total mass of a vehicle is provided. The method comprises the steps of providing a plurality of speed sensors configured to sense a rotational speed of a plurality of components of a driveline of the vehicle, estimating an output torque of the driveline of the vehicle, calculating gear losses based on the output torque of the driveline, estimating friction losses based on a rotational speed of a torque converter, calculating a rolling resistance of the vehicle, calculating an inertia of the vehicle, and estimating the total mass of the vehicle based on the inertia of the vehicle. The method uses currently available sensors found in a vehicle transmission to estimate a total mass of a vehicle or a vehicle payload.

Abstract: A method and an apparatus for controlling a wet clutch are provided. The clutch comprises a pump, a piston, and a fluid conduit. The pump provides a housing with a hydraulic fluid. The piston is movably disposed in the housing and is movable into an extended position by a preloaded spring and into a retracted position by applying an engagement pressure on the piston by the hydraulic fluid. In the retracted position torque is transmittable through the clutch. The fluid conduit connects the pump and the housing. The method comprises the steps of prefilling the clutch by applying a prefill pressure on the piston, prefilling the fluid conduit line and the housing with the hydraulic fluid. The prefill pressure is lower than the engagement pressure required to move the piston into the retracted position.