Abstract: A snowmobile of the type comprising a conventional front ski assembly and endless track but also a rear ski assembly and characterized by the latter, being pivotally connected relative to the body of the snowmobile and adjustable in height relative to the rear end of the endless track for improved longitudinal stability and comfort, better longitudinal load distribution and adjustment in relation with the condition of the snow on the ground and the desired traction. A suspension arm system resiliently and adjustably attaches the rear end of the endless track and the rear ski assembly to the body of the snowmobile with a remote control for selective adjustment of the height as aforementioned.