Corvette leaf spring commonly refers to a type of independent suspension that utilizes a fiber-reinforced plastic (FRP) mono-leaf spring instead of more conventional coil springs. It is named after the Chevrolet Corvette, the American sports car for which it was originally developed and first utilized. A notable characteristic of this suspension configuration is the mounting of the mono-leaf spring such that it can serve as both ride spring and anti-roll spring. In contrast to many applications of leaf springs in automotive suspension designs, this type does not use the spring as a locating link. While this suspension type is most notably associated with several generations of the Chevrolet Corvette the design has been used in other production General Motors cars, as well as vehicles from Volvo and Mercedes-Benz. Fiat produced cars with a similar configuration, using a multi-leaf steel spring in place of the FRP mono-leaf spring.
The leaf-spring suspension configuration is independent, because the movement of one wheel is not determined by the position of the other.Control arms are utilized to define the motion of the wheel as the suspension is compressed. The usual coil springs are replaced with a single FRP spring, which spans the width of the car. As in independent suspension systems using coil springs, and unlike the common leaf-spring supported Hotchkiss rear axle, the suspension kinematics are defined only by the control arms.
As in a coil-spring suspension design, the FRP mono-leaf spring supports the weight of the vehicle. However, the FRP leaf springs differ from steel coils and traditional steel multi-leaf springs in a number of significant ways. The FRP plastic springs have 4.3–5.5 times the strain energy storage per weight, compared to steel. This results in a lighter spring for a given application. The single FRP mono-leaf front spring used on the fourth-generation Corvette is 33 percent of the weight of an equivalent set of coil springs. Comparing FRP to conventional steel leaf springs in similar applications, the weight saved is even greater. The third-generation Corvette offered an optional FRP mono-leaf spring as an alternative to the standard multi-leaf steel spring, the 22-kilogram (48 lb) steel spring being replaced by a 3-kilogram (7 lb) FRP spring. Volvo claims a weight savings of 5 kilograms (10 lb) by using a FRP spring in the rear suspension of its second-generation XC90, compared to designs using coil springs. In addition to the reduction in vehicle weight, the weight of the spring is partly unsprung mass.