A traction assembly for replacing a wheel on a vehicle is disclosed. The traction assembly uses a traction band disposed about a sprocket wheel, idler wheels and road wheels for propulsion. The idler wheels and road wheels are pivotally mounted to a support frame which is coupled to the sprocket wheel via a support arm. The support arm is pivotally yet non-drivingly connected to the sprocket wheel and is pivotally connected to the support frame. The support arm is able to pivot forwardly and rearwardly, albeit in a limited fashion, with respect to the support frame. Such forward and rearward pivotal movements allow the weight of the vehicle to be transferred on the trailing portion, i.e. either the front or the rear portion, of the support frame depending on the direction of movement of the vehicle, thereby generally preventing the leading portion from diving or digging into the ground.