A dual rate shock absorbing apparatus for a suspension
system of a heavy off-road vehicle including a housing having two axially elongated members. A dual rate spring
package is disposed in the housing. Such spring
package includes a first spring
assembly for absorbing, dissipating and returning a first predetermined level of energy imparted to the shock absorbing apparatus. One end of the first spring
assembly acts against a closed end of the housing and a second end acts against a spring seat. A second spring
assembly absorbs, dissipates and returns a second predetermined level of energy. One end of the second spring assembly acts against an opposed closed end of the housing and a second end acts against the spring seat. An axially elongated guide assembly, extending substantially the cumulative length of the first and second spring assemblies, controls
axial compression of the first and second spring assemblies. An operable length of the guide assembly is automatically adjustable to the length of the housing during operation of the shock absorbing apparatus. An apparatus for monitoring loads applied to the shock absorbing apparatus is also provided.