Leaf springs are some of the oldest mechanical devices conceived by man; dating back to medieval times. They are still being used to this day because they work. They support the vehicle’s weight, they conform to the terrain, and they locate the axle. They also distribute the load on a large portion of the frame. Leaf springs are far from an outdated design; they are found on the latest Chevrolet Corvette suspension. The Corvette uses a high-tech composite, transverse mono-leaf, but it’s still a leaf spring.
Unfortunately, leaf springs have gotten a bad rap. When improperly designed, they can be harsh. Some spring suppliers, including the manufacturers, use thicker and fewer leaves to reduce cost. They also design them to be one size fits all. To ensure you get the advertised height, they make them towards the stiff end of the scale. However, a properly designed leaf spring can hold your truck up and give a comfortable ride.
Custom spring makers blueprint the leaf packs, designing them to match your vehicle’s weight and intended use. They are carefully hand crafted and use additional leaves to give you a nice progressive spring rate. They use multiple leaves of different widths, lengths and thicknesses to be supple at ride height for a smooth ride but still have the beef to take on rough terrain. One such spring maker is Atlas Spring in City of Industry, California. They built a custom set of springs for a Ford F-350 that regularly hauls a camper into remote areas. The factory springs were built to simply haul a load; this truck needs to haul something else. If they can make this 10,000-pound rig comfortable and controlled in the dirt, they can make your rig do the same.