Design, development, and application of a compression type 100% rubber spring has proved to be very successful on single and tandem axle suspensions for trucks and trailers.
Among the objectives of the rubber spring were a free height, not to exceed 8 in, static capacity of approximately 20,000 lb, a load deflection of about 3 in, and a life of 500,000 miles or more.
Desirable characteristics have proved to be smooth ride due to low frequency of pitch, minimum of side sway or roll, long life-no spring has yet worn out despite hundreds of thousands of miles of service.