**(Revised) The apparent failure of the 1962 E-Z Pack SRL-20 rear loader spurred Hercules-Galion to develop a more conventional design that would appeal to customers that were used to models from Gar Wood, Heil and Leach. By February of 1964, the first ads for an all-new rear loader appeared in American City Magazine. **
The new model, dubbed the Super Hopper, due to its generous 2.5 yard capacity hopper, was initially available in 13, 16, 20 or 25 cubic yard capacities, and featured ejection unloading. It was a collaborative effort between Bill Herpich, George W. Palmer and John Sand. Herpich was vice president and director of engineering at Hercules-Galion, and would soon been appointed executive vice president of all truck operations. By 1965, he had amassed 40 U.S. truck body patents, and would figure prominently in E-Z Pack's early years. John Sand had collaborated with Herpich on the original Hydro E-Z Pack a decade earlier.
The diagram above illustrates the unique packing mechanism, which was based loosely on Cyril Gollnick's original Leach Packmaster, but with some key differences. Where the Packmaster had utilized a single curved track and with swing link stabilizers, the new E-Z Pack featured two separate tracks (yellow highlights). The lower track was circuitous, and controlled the single blade during its movement in the hopper. One-way gates (red highlights) maintained proper movement of the blade as the hydraulic cylinders were reversed during the normal packing cycle. The latches could also be manually unlocked in the event of a jam which required reversing the cycle. The near-vertical upper track performed the function of stabilizing the blade. Only three cylinders were used in the entire body; one telescopic ejector cylinder, and two packing rams which doubled as tailgate lifts (a blocking pin was inserted into the roller track to effect lifting of the tailgate. A heavy-duty, four-point underbody latch secured the end gate structure to the body.
1-2 yard containers could be handled with chains attached to the packer blade, or an optional overhead winch could be added for cans up to ten yards. The tailgate structure was rugged and had no valves or hydraulic plumbing. Controls were servo-electric, with manual controls as a back-up. From an engineering standpoint, the E-Z Pack Super-Hopper rear loader must be considered a triumph for its time. The practical design borrowed heavily from Leach, yet simplified many of the complexities of the Standard Packmaster, and thus avoided infringing on patents. The 2.5 cubic yard hopper was among the largest in the industry, and the new body rounded out a diverse and solid product line. E-Z Pack division would seem to be in a position of strength at mid-decade. However, there was trouble on the horizon, beyond the control of Bill Herpich or anyone else at Hercules-Galion.
An early model 25-yarder in front of the Hercules-Galion factory
Some of the features of the E-Z Pack rear loader
1-2 yard hoist system using packer blade was actually pioneered by Leach
Later 1960s model shows a beefed-up packer blade structure
1968 trade ad for the E-Z rear loader
An amazing living classic: Super Hopper rear loader still on the job collecting refuse for a northern California trailer home community.
**(Revised) The apparent failure of the 1962 E-Z Pack SRL-20 rear loader spurred Hercules-Galion to develop a more conventional design that would appeal to customers that were used to models from Gar Wood, Heil and Leach. By February of 1964, the first ads for an all-new rear loader appeared in American City Magazine. **
