The Hundred Series: 1958 Oliver 770 Diesel Tractor

By the late 1950s, Oliver was still a major player in the tractor market, but more and more, bigger players were overshadowing the manufacturer. Oliver unveiled an updated line of tractors in 1958; today they are known as the “Three Digit” or “Hundred Series” tractors. The 550 came first, followed shortly by the 770 and 880 and a bit later by the big boys, the 950, 990 and 995. By 1960, a smaller 440 became the light utility tractor in the lineup.

The Hundred Series tractors were intended to build on the fine reputation of the 1954 and up “Two Digit” Super series they replaced, carrying over a lot of the older tractors’ DNA. The most obvious difference was the styling: gone were the sweeping lines that went back to the Fleetline Olivers of the 1930s. The new tractors were more angular and the color scheme was altered. The signature Meadow Green was retained as a primary color, but the red and yellow highlights were replaced by Clover White.

The operator’s station on the 770 is standard fare for the period. Oliver bragged about its rubber torsion seat springs but this was the era when farmers began to demand more comfort. Power steering was an option on the 770. Nafziger’s tractor was either not ordered with the Power-Booster, or it was later removed. It isn’t unusual to see it removed these days because clutch wear in the unit could put the tractor out of action if it was worked too hard.

Underneath the skin, some of the tractors changed a lot and others changed very little. The 216-cid Waukesha diesel available in the 770 was largely the same, but an increase in maximum engine speed from 1,600 to 1,750 rpm delivered a small increase in power (about four belt and eight drawbar horsepower).

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The big news had to do with the final drive. Oliver added an optional shift-on-the-fly step-down, dubbed by marketing as the Power-Booster. It allowed farmers to split gears on the six-speed main transmission without using the clutch. This dropped the gear ratio by 24 percent and came in handy when encountering a hill or patches of what farmers call “tough ground.” Initially, the 770 kept the previous sliding gear transmission but the 880 got a new constant mesh, helical gear transmission. Later 770s got a similar transmission upgrade. Another new feature for the Hundred Series was the Power-Traction hitch, Oliver’s version of draft control.

Looks like this is still a working tractor. Nafziger’s Oliver is hitched to an Oliver three-bottom plow that looks well (and recently) used. Oliver was well known for their high-quality plows, and the Oliver tractor originated in 1929 when the Oliver Chilled Plow Works absorbed the ailing but well-known Hart-Parr company. Oliver wanted to build tractors and an established line made it a turnkey operation. It took nearly a decade for the Hart-Parr name to fade away completely.

Like the Super 77 that preceded it, the 770 came in several configurations. As with the 1958 770 shown here, the narrow front axle was still available but becoming increasing less popular. An adjustable wide axle was often combined with power-adjusted rear wheels for rowcrop use. Oliver also offered the 770 with a standard fixed-width wide axle or in a wheatland configuration with a heavy fixed-width front axle. Among the rarest 770 configurations are the high-crop and orchard models. Oliver also built a 770 Industrial, which featured yellow paint and an optional shuttle shift called Reverse-O-Torc that allowed clutchless shifts from a forward gear to reverse.

Oliver had a long-standing relationship with Waukesha, itself one of the earliest developers of diesels in the U.S. The 770 had a 216-cid Lanova cell diesel while the similarly-sized 880 series used a 265-cid engine with similar architecture, the main difference being a quarter inch of bore and stroke. The displacement difference was worth almost a 15 horsepower.

Waukesha had licensed the Lanova cell combustion chamber from its German patent owner in the early 1930s. An energy cell was located directly across the cylinder from the injector. It had a narrow entrance and two inline chambers. When the injector opened, fuel was sprayed into the energy cell as well as the cylinder. Combustion started in the cylinder but spread into the energy cell. Higher pressure was developed in the confined spaces of the energy cell and when the combusting fuel blew back into the main combustion chamber, it created turbulence that mixed up the remaining fuel in the cylinder.

Because combustion occurred in several stages, similar to the way pilot injection is used today, the engines were very quiet. If they had a downside it was being particularly susceptible to injection problems and carbon buildup in the Lanova cells. Oliver used Lanova cell diesels into the 1970s, but their ultimate demise came because they were largely unsuitable for turbocharging.

The 770 model was built until 1967 but big changes happened to Oliver before the end of production. In 1960, White Motor Company bought Oliver and operated it as a wholly owned subsidiary. In the short run that was a good thing, because Oliver had begun to struggle. In the long run, though, ownership by White resulted in Oliver and Cockshutt products being homogenized. The Oliver name would begin to disappear by the end of the 1960s in favor of the White nameplate. DW