A gear shifting system for a change gear transmission having means for engaging and disengaging a selected gear ratio said gear shifting system comprising: - means (6,16,18,21) for selecting a gear ratio and means (7,8,19,21) for activating said gear shifting means to engage or disengage a selected gear ratio; - a shift shaft having a longitudinal axis and supported in supporting means to be shiftable in an axial direction and rotatable around its longitudinal axis; - operating means secured to said shift shaft and adapted to control said means for engaging or disengaging a selected gear ratio in response to rotational movement of said gear shaft, - first actuator means operatively coupled to said shift shaft to shift the same in axial direction to select a gear ratio to be engaged or disengaged; - second actuator means operatively coupled to said shift shaft to rotate the same around its longitudinal axis to engage or disengage a selected gear ratio; - said second actuator means including remotely controlled shift actuator means connected to an actuating rod having a longitudinal axis and slidingly received in a tube-like shifting rod; - a fluid operated power assist servo unit operatively interposed between said actuator rod and said shifting rod to exert an amplified axially directed actuating force on said shifting rod in response to an axially directed actuating force exerted on said actuating rod by said shift actuator means, said shifting rod being coupled with said shift shaft to rotate the same around its longitudinal axis in response to an axial movement of said shifting rod; - a housing enclosing said power assist servo unit and means for supporting said shifting rod and said actuating rod within said housing; wherein - said shift actuator means are associated with said housing and said gear system being characterised in that: - said actuator rod is non-releasably operatively connected with said shift actuator means. - means (6,16,18,21) for selecting a gear ratio and means (7,8,19,21) for activating said gear shifting means to engage or disengage a selected gear ratio; - a shift shaft having a longitudinal axis and supported in supporting means to be shiftable in an axial direction and rotatable around its longitudinal axis; - operating means secured to said shift shaft and adapted to control said means for engaging or disengaging a selected gear ratio in response to rotational movement of said gear shaft, - first actuator means operatively coupled to said shift shaft to shift the same in axial direction to select a gear ratio to be engaged or disengaged; - second actuator means operatively coupled to said shift shaft to rotate the same around its longitudinal axis to engage or disengage a selected gear ratio; - said second actuator means including remotely controlled shift actuator means connected to an actuating rod having a longitudinal axis and slidingly received in a tube-like shifting rod; - a fluid operated power assist servo unit operatively interposed between said actuator rod and said shifting rod to exert an amplified axially directed actuating force on said shifting rod in response to an axially directed actuating force exerted on said actuating rod by said shift actuator means, said shifting rod being coupled with said shift shaft to rotate the same around its longitudinal axis in response to an axial movement of said shifting rod; - a housing enclosing said power assist servo unit and means for supporting said shifting rod and said actuating rod within said housing; wherein - said shift actuator means are associated with said housing and said gear system being characterised in that: - said actuator rod is non-releasably operatively connected with said shift actuator means. - said actuator rod is non-releasably operatively connected with said shift actuator means.