The rest of the axles on the vehicle are nearly the same as the front steer axles, with a few differences. What are the differences?

There are FOUR differences between the steer axle, and the tractor and trailer axles. They are the Torsion bar, the space between the axles so bud rims or spacers, tread depth changes from four thirty seconds to two thirty seconds, and retreads are allowed on every axle but the steer axle, and the airbags portion of the suspension.