In Western Canada, log-transportation costs are often the highest phase cost of supplying wood to the mills. The industry has attempted to reduce costs by adding axles to trailers to increase the legal payloads. However, with increased payloads, traction has become a limiting factor for Class 8 tractors, especially in the off-highway portion of the log hauling cycle. In response, FERIC initiated a feasibility study in 1989 to investigate the potential of a tridem tractor addressing the industry's needs for improved tractive performance. A computer simulation indicated that a tridem tractor has more tractive ability than the conventional tandem drive tractors, and that log truck combinations with a single articulation point are more dynamically stable than those with two or more articulation points. The principal drawback predicted by the simulations was a reduced level of steering responsiveness for the tridem tractor configurations. The report recommended that a tridem tractor be evaluated while in revenue service to verify the simulation results, and that operational costs and productivities be determined (Amlin 1992).