Kohler Enters Truck Industry

New 5 kW diesel APU builds on company's expertise.

A household name will soon be found in a new location: riding along on the nation's interstates attached to the chassis of over-the-road trucks. Kohler is taking its 85-plus year history in the power generation market and expanding its generator product line to include an auxiliary power unit (APU) for the heavy-duty trucking industry.

Production is expected to start later this year at Kohler Power System's generator factory near Sheboygan, WI. More than 10 different engine models are shipped to Kohler's plant, where they are installed in dozens of different generator configurations destined for applications ranging from yachts to giant hospitals. The Kohler APU will have its own production line.

While Kohler may be a new name in the heavy-duty truck market, it's not new to vehicle-mounted generator systems. It has been keeping the lights and televisions on in motorhomes since the 1950s.

The new Kohler 5 kW APU will offer trucking fleets, OEMs and truck owners/operators the only air-cooled APU with its power capability in the side-rail mounted size. The air-cooled, self-contained Hatz diesel engine means less intrusion into the truck's critical systems.

Understanding that compactness is crucial, Kohler designed the product to be one of the smallest and lightest air-cooled generators on the market, weighing under 350 lbs. The unit is encased in a sound-attenuated enclosure for quiet operation, with single-side servicing.

With an APU on the drawing table for several years, Kohler did a considerable amount of research to understand what truckers wanted.

"We visited dealerships, owner operators, service stations, fleet owners, and large haulers," says Chris Baldwin, director, Kohler Mobile Generator Business. "We also spent a lot of time with the OEMs, which was very valuable."

While truckers could tell Kohler's engineering and marketing team what they wanted in an APU, the truck manufacturers gave them important technical information such as operating conditions and test parameters.

"OEMs gave us the detailed specifications for vehicle vibration, for example, or what conditions they test to for Death Valley heat such as the specific tolerances on the temperature for various components," says Baldwin. "Owner operators say they just want it to work in both Tucson and Montreal, and don't want to worry about it. But the OEMs outlined the detailed challenges we couldn't have imagined."

The Kohler APU (5 kW, 120v AC power plus 50-amp DC battery-charging power) is designed with a direct-drive alternator. By eliminating the alternator belts found on competitive models, Kohler can offer increased reliability and reduced maintenance concerns.

The Kohler Advanced Digital Controller, developed in-house, will come standard on the new APU, which allows the driver to start and stop the generator, and adjust the heating and cooling from inside the cab. The digital controller also features an easy-to-read LED screen that displays up to 13 operational conditions.

While Kohler anticipates selling most of its APUs to aftermarket customers in the near term, "we would be more than happy to work with any or all of the major OEMs," says Baldwin.