1961 H-Series (Hydraulic)     The decade of the 1950s was a time growth for Pak-Mor Manufacturing, who had taken the basic circular side loader to a national market, and pioneered in the field of bulk hauling and transfer trailer technology. But by 1960, the chain-driven Pak-Mor (little changed from the San Antonio trucks of the forties) was beginning to show its age. The competition within the refuse body industry was intense, and technical milestones such as the Leach 2-R Packmaster and Heil Mark II were setting new standards for compaction density. Even the circular side loader field, once the exclusive domain of Pak-Mor, was becoming crowded. One of Pak-Mor's major east coast distributors, Truck Equipment Company, had begun to manufacture their own side loader, the all-hydraulic Truxmore Pakker. The following year, Seal-Press, located right in San Antonio, would convert their own existing side loader to all-hydraulic power. The new 1961 Pak-Mor H-Series all-hydraulic side loader     In the face of this competition, Pak-Mor went on an aggressive engineering program to modernize its existing product line, and expand into rear and front loader territory as well. First up was an all new hydraulic version of the Pak-Mor barrel truck dubbed the H-Series, created by designers William Ferrari and Orin Anderson. Unlike its rivals, Pak-Mor mounted the double-acting telescopic packer ram horizontal, close to the floor, rather than at an angle from top to bottom. It was claimed to transmit more of the packing force, 78,000 pounds of pressure, directly on the load, without frictional losses that occur in angled designs. The packer plate was carried on six rollers guided by two rails at the base. A large protrusion in the lower part of the packer plate accommodated the cylinder.     The design also featured dual-side packing controls, and a large capacity hydraulic oil reservoir located at the upper front of the body to improve cooling. A Dynamic Sweep lever allowed the operator to rapidly clear the loading area (in ten seconds) to speed up loading. Full pressure packing could then be applied later as needed. Extra overlap was provide on cylinder stages to prolong gland life. Manually locked barn doors as used on the original were carried over. The old chain-driven Pak-Mor was still produced as an economy model, and was now designated the I-Series. Inside the H-Series showing horizontal ram. Dynamic Sweep featured cleared hopper area (red highlights) in ten seconds The Handi-Lift could be added to any H-Series, to handle containers of 1.5 to 4-cubic yards capacity Handi-lift was ideal for alley collection, and winch cables could reach out six feet to position container, even from offset angles. A kick-out "return spotter" alleviated the need to manhandle the empties. Optional hydraulic hopper door shown, lower right. Lo-Boyes became hydraulic also, now up to 38-cubic yards capacity. The pack cylinder was located much higher, with 18 inches of overlap between each section to provide maximum rigidity when extended. Fantastic demonstrations (lower right panel) illustrate the packing prowess of these machines. Various H-Series models, and Lo Boye trailer equipped with Handi-Lift system Hydraulic compaction gave larger hand-loaded bodies like this tremendous capacity When automated side loader (ASL) arms began to be developed in the early 1970s, Pak-Mor was a 'go-to' supplier of bodies. The circular H-series bodies were easily adapted to almost any loader arm configuration, and had tremendous packing power. This is a Litter Lift loader from about 1975. When no one else could supply a trailer low enough to fit beneath the ash pits of the Miami, Florida incinerator, Pak-Mor modified one their circular trailers to do the job. Drain taps at front of body allowed removal of excess water before transport. The ability to create these customized versions to a customers specification made Pak-Mor a leading supplier of transfer trailers. To keep up with the rapidly expanding refuse transfer market, 1962 Saw the introduction of Pak-Mor rectangular compaction trailers. This is a 60-cubic yard 1966 model used by Winter Park, Florida. SELECTED PATENTS Patent # Description Inventor Assignee Date US3161305 Refuse vehicle with load compacting and... Ferrari, et.al. Pak-Mor October 9, 1962 US3232461 Container positioning mechanism Dean Pak-Mor April 10, 1963 4/5/09 (updated 6/5/22) © 2009 All Rights Reserved Photos from factory brochures/advertisements except as noted Logos shown are the trademarks of respective manufacturers