Editor's note: An earlier version of this story incorrectly said Ram pioneered coil spring rear suspension on full-size pickups. Chevrolet C10 pickups carried the technology in the 1960s. Ford's ...

Rassini’s 1+C Hybrid leaf spring features a single steel parabolic main plate and a flat glass fiber composite helper plate to provide suspension on the rear wheels of the Ford F-150 pickup truck.

Rassini has developed and manufactures the hybrid rear suspension, which consists of a parabolic main steel leaf supported by a composite helper, at its Piedras Negras (Coahuila Mexico) location. With ...