Canadian regulators utilize the ESAL concept for vehicle impact evaluations and(or) pavement design. Unfortunately, TAC’s ESAL equations do not account for tire size and, consequently, overestimate steering axle impacts when those axles are equipped with widebase steering tires. Many new vehicles proposed for use in Canada feature tridem-drive tractors and heavily loaded steering axles—these heavy loads necessitate the use of widebase steering tires. In order to optimize high efficiency truck configurations in Canada, therefore, accurate estimates of widebase steering tire ESALs are needed. This work describes a methodology to estimate ESALs for widebase steering tires. These ESAL equations were used to justify an increase in steering axle weights for B.C. 9-axle log B-trains.