Patent attributes
A control method is provided for a powertrain in a vehicle, the powertrain including an engine mechanically connected to a gearbox and an Electronic Control Unit (ECU), wherein the method includes allowing an extraordinary gear shift in spite of a first torque comparison indicating an expected engine output torque demand above a first general limit for allowed output torque associated with the extraordinary gear shift provided that: a second torque comparison indicates that the expected engine output torque demand after the extraordinary gear shift is within the limits of a second temporarily increased allowed engine output torque limit; and an extraordinary gear shift criteria is fulfilled indicating a gear shift is allowed the criteria being dependent on at least one parameter chosen among estimated fuel efficiency, engine efficiency, expected future torque demand, time of running the engine above the general engine torque limit and engine temperature.
