A method for controlling the primary motor of a load carrying vehicle， a system for controlling the primary motor of a load carrying vehicle， and a load carrying vehicle， such as a forwarder

Method for controlling the primary motor of a load transport machine. The load transport machine is arranged to be driven on land， at least off the road， alternately empty and loaded. The method identifies a working step of a load transport machine， which typically lasts at least 2 minutes; determining a value for at least one control parameter of the primary motor of the load transport machine using the identified work step; and controlling the primary motor of the load transport machine by the value of said primary motor control parameter. In addition， a primary motor control system comprising a control computer and means for transmitting the value of the primary motor control parameter to the primary motor control unit and is arranged to perform the described method by means of said control computer. In addition， a load conveying machine， such as a forwarder， comprising such a control system.