Classic Refuse Trucks GAR WOOD

Load-Packer

By 1938 Gar Wood was already the world's largest truck body builder, and the Load-Packer positioned them to dominate the packer body market for the next decade. Production models through the 1940's underwent some minor but significant changes.

Early in production, the barn-doors on the ram panel were replaced by a single spring-loaded, manually operated door (below). This door design would remain until 1951. Refuse was loaded through the open ram panel, and then the door was closed and latched shut prior to starting the power packing cycle. Thus, these were sometimes referred to as the "Slam Door Gar Woods" by the men who operated them.

At left is a City of Detroit Load-Packer, Type A, from a September, 1939 advertisement. The top-hinged door is the obvious difference, and as mentioned this would become a standard feature through 1951 when the LP-200 series was introduced.

However, also note the heavy reinforcement made to the packer ram, particularly the bell-crank arms that connect the hydraulic cylinders to the panel which are massive compared to the early barn-door models shown previously. As with any new design, Gar Wood probably corrected many weaknesses found only after a number of units had been in actual, day-to-day service.

The following diagram describes the packer mechanism of Load-Packers of the 1938-1951 period:

There were minor cosmetic and structural differences among the early Load-Packers, but they all used the same basic packer layout, consisting of a ram panel and a retaining panel. Figure 1 shows how loading the hopper is accomplished through a door (manually opened) in the ram panel. The retainer panel is latched in postion, holding the previously compacted load.

In figure two, the packing cycle is ready to begin. The operator first closes and latches the ram door, then pulls the control lever. Then the retainer panel snaps open, (under heavy spring tension) moving rearward over the hopper load until it contacts the back of the ram panel.

Now, twin hydraulic cylinders force ram panel forward into body. Retainer panel is also forced forward and acts as a "shear", sliding down and progressively scraping the back of the ram panel during its travel. At the end of forward travel, retainer panel engages one-way latches which lock it in this position. Ram panel then reverses direction, stopping at the edge of the tailgate, and hopper is ready for another load. Since the ram panel has to return back through the hopper, the total cycle time and "reload time" are the same. That is to say, no refuse could be added to the hopper until the total cycle was completed.

Primitive by modern standards, these packers were highly advanced for their time. Note the position of the hydraulic cylinders in relation to the ram panel, an arrangement which was to form one half the Cyril Gollnick's slide/sweep method used on the Leach 2R Packmaster, and still in common use today.

The 1946 Load-Packer shown above gives a good view of the mechanism with the ram panel in the load-compressing position, and shows the changes made to the tailgate structure on later models. Later models were designated as B, C and D models in the Gar Wood manuals, even if they may not have actually had such designation on the individual body identification plates. The biggest change was the tailgate side walls, which were much higher than earlier versions. The higher side walls formed supports for the ram panel pivot bearings, a critical stress point in the tailgate assembly.

A view of the control linkage and packer cylinders on a restored 1940's Load-Packer. Lou Carollo of New York rescued this 12-yard body from an Oklahoma salvage yard and spent seven years restoring it.

Inside-the-hopper view shows the inner face of the load retainer panel. This panel is difficult to see externally. It performs the vital function of securing the compressed load within the body, limiting "fall back" of refuse into the hopper.

8/1/04 (revised 1/24/09)