Abstract: An improved suspension system for a mobile machine adapted to work a material associated with a horizontal surface includes a frame mounting a prime mover. An arbor shaft extends transversely across the frame adjacent to a front end of the machine and is drivingly connected to the prime mover. The suspension system includes a live rear axle and a front axle assembly that is extendable and retractable whereby the machine is movable between raised and lowered positions. A rotating tool is mounted on the arbor shaft. Lowering the machine from its raised position engages the tool with the material. The improvement to the suspension system comprises a support device for providing extra support to the frame when the machine is in its lowered position, the support device being adapted to stabilize the machine when the tool exerts an upward reactionary force on the machine front end.