Abstract: A conversion arrangement for converting a conventional rear wheel drive road vehicle to a snowmobile comprises a subframe upon the sides of which are mounted track support wheels and tracks with the subframe attached to the vehicle through the conventional rear suspension springs. At the front end of the subframe is a pair of forwardly extending levers which are attached to the front wheel hubs of the vehicle and carry skis. The skis are vertically movable under control of the vehicle front suspension by pivotal movement about a shaft at the front edge of the subframe with the amount of movement limited by the addition of an arcuate stop arrangement which cooperates with a tongue extension on the lever system. The rear drive axle of the vehicle is moved from its conventional position on the springs rearwardly to a position at a rearmost edge of the subframe with an additional drive shaft added between the vehicle drive shaft and the vehicle back axle for communication of drive.