Today we have a case study in axle position with the Western Star 4700. If you went to the dealer today to order a brand spanking new 4700 you would be presented with a variety of options to make your future truck unique to your needs. One such choice is the axle position. With the 4700 series you have two choices in this regard, a set forward or set back axle. The orange plow truck below is a set forward model which means the axle is closer to the front of the truck. So why go with this setup? I’ll spare you the mumbo jumbo about the Bridge Formula, GAWR, and GVWR by cutting to the chase. Most truck buyers prefer the look of a SF truck as it allows for fuel tanks and battery boxes to be located under the cab, resulting in a cleaner and more traditional look. Besides the cosmetic factor a set forward axle will send more weight to the back axles which is important with a dump truck.
Now this Western Star is also a 4700 but with a set back axle. You’ll notice the wheels are closer to the cab of the truck. The big advantage with a SB setup like this one? Turning radius, it’s tight, perfect for a truck like this roll-off that will need to get it to some very tight spaces over the course of its career.