Leaf Springs & Components

Leaf springs are the oldest type of springs, dating back to the days of horse-drawn carriages. While full elliptic, three quarter elliptic, and quarter elliptic designs have been used in the past, today the most common design for automotive use is the semi-elliptic, where two leaf springs mounted parallel with the frame rails not only provide spring function but also locate a solid axle on the vehicle. Single leaf springs have also been used with independent front and rear suspensions where the spring is mounted transversely.

A leaf spring is composed of one or more lengths of arched spring steel. Single leaf springs are called mono leaf springs, while multi leaf springs have a main leaf and several progressively shorter leaves joined together by a central bolt or pin, with rebound clips to hold the leaves together. The ends of parallel mono or main leaves are typically formed into “eyes” at each end to accept the bushings through which the spring-to-frame mounting hardware is installed. U-bolts and mounting plates secure the springs to the axle.

With parallel leaf springs, one end of the spring is usually mounted to the frame with a hanger, but because leaf springs elongate as they compress, shackles are commonly used to allow for movement at the other end, with one end of the shackle attached to the spring and the other end to another frame-mounted hanger. Small, lightweight cars are generally equipped with mono leaf springs, while multi-leaf springs are used on heavier vehicles and for carrying heavy loads, which is why they are regularly used at the rear on trucks. Because leaf springs support the vehicle weight and connect the axle to the vehicle, in effect spring and suspension member, their condition is critical to vehicle safety.

The most common symptom of worn springs and reason for spring replacement is incorrect vehicle ride height. Sagging springs and/or bent or broken leaves will lower the chassis of the vehicle at one end or even one corner of the vehicle, which can result in bottoming out, poor handling and abnormal tire wear. Vehicle manufacturers publish ride height specifications. Measure the ride height at the recommended locations and compare the measurement with specs. Along with checking the springs for cracks and missing or broken leaves, the shackles, spring eye bushings, hangers, U-bolts and pins should also be inspected for wear, looseness and damage as these can also cause incorrect ride height, poor handling and noise.

If measurement and inspection proves your springs are in need of replacement, we have the original equipment specification leaf springs that will restore ride height and ride quality. Plus, no matter whether you’re repairing a daily driver or restoring a classic, we also have all the parts you need for a complete repair and to make sure the spring is mounted properly – spring eye and shackle bushings, complete shackle and spring hanger assemblies, U-bolt kits, plates and spring pads, and much more. And if you need to haul heavier cargo in your pickup, we have helper springs in a wide range of load capacities. They’re designed to be used with your OE springs and won’t adversely affect ride when you’re driving unloaded.