It’s called the Unimog, and it’s unlike any truck you’ve seen before. In fact, according to Robert McTernan, Freightliner’s newest vocational vehicle isn’t a truck at all. “It’s really more of a system,” says McTernan, director of Unimog’s North American operations. “It can carry heavy payloads up to 70 mph, but it also has two powerful hydraulic systems and can quickly change out more than 1,000 different attachments on its front or rear chassis.”
Unimog is a German acronym for Universal Moteren Geraet. Translated to English, this means “Universal Tool Carrier,” and is reflected in the vehicle’s ability to run eight separate hydraulically powered hand tools at once, or two high-pressure attachments like a front-mounted rotary asphalt cutter or rear-mounted backhoe.
As a concept, the Unimog isn’t new – at least not to Europeans. The first examples rolled off Mercedes-Benz assembly lines in 1951. The truck’s robust frame, suspension and four-wheel-drive system were crafted to meet an immediate need: rebuilding war-ravaged Europe. As a concept, the Unimog proved so successful that more than 100,000 units had been built by 1966. In 2001, the truck celebrated its 50th anniversary.
Of course, Mercedes kept upgrading the Unimog’s design. The current version was launched in 2000 in Europe. Currently the Unimog line consists of three different models, although only the U500 model – with two different wheelbases and gross vehicle weight ratings of either 26,000 or 33,000 pounds – will initially be offered in North America.
Specialized components for construction applications
Because the U500 is designed to work in ways conventional trucks can’t, it features a host of highly specialized components. The truck’s Mercedes-Benz 0M900 six-cylinder diesel engine is available in two horsepower ratings – the standard 230-horsepower version or a 280-horsepower unit allowing highway speeds up to 70 mph. Dual-circuit, four-wheel-disc, anti-lock brakes and a permanent, full-time, all-wheel-drive system with rear differential lock are also standard. A front differential lock can be spec’d as an option.
The Unimog’s standard transmission is an eight-speed, electro-pneumatic unit featuring Telligent automated manual shifting. There’s a bit of a learning curve here for American drivers unfamiliar with this type of transmission, although it’s not an insurmountable one. To shift gears, the driver first toggles the selection lever either up or down and then engages the clutch to initiate the shift. The sequence is a bit odd for drivers honed on conventional manual units, but the transmission shifts so smoothly, and allows such easy skipping of unneeded gears, most drivers should master it quickly.
The electro-pneumatic transmission is also available in an optional 16-speed-deep-reduction version for high torque applications. It’s this transmission that allows the Unimog to work effectively with a front grading blade, loader bucket, asphalt cutter, rear-mounted trencher or in any application that requires extremely low gear ranges. The transmission’s Electronic Quick Reverse system allows fast and easy shifts from forward to reverse gears in low-range applications using sweepers or blades that require constant backing.
In addition to its two powerful hydraulic systems, the Unimog can be equipped with an engine-driven front PTO and a transmission-driven rear PTO.
The hydraulic systems allow the Unimog to simultaneously operate two attachments at once, without compromising performance. At the same time, the front and rear PTOs can mechanically power attachments such as brush cutters, tree trimmers and mowers, either independently or in conjunction with the hydraulic systems. A front-mounted adaptor plate, similar to a hydraulic coupler, allows the Unimog’s driver/operator to quickly switch from one attachment to another. “Most attachment changes can be made in a minute or less,” McTernan notes. “But even the most complex Unimog attachments can usually be changed out in 30 minutes or less, using standard wrenches and tools.”
The Unimog can also be used as a rolling power source. Each hydraulic system has four ports mounted on the front and rear bumpers, allowing the use of hand-held tools such as concrete saws or jackhammers. Easily accessible electrical ports allow the Unimog to power an equally large array of tools, from circular saws to small light towers.
Optimized design features low center of gravity, high ground clearance
The Unimog’s entire design reflects its unique truck/machine application. “A standard set-back front axle allows deep wheel cuts,” McTernan notes. “It also gives us room for the heavy-duty front mounting plate and increases the truck’s stability when carrying heavy front attachments.”
A narrow body width of 90.5 inches and a lightweight upper body structure combine to give the Unimog an extremely low center of gravity. It can easily negotiate grades of up to 70 percent head-on. A beefy high articulating coil spring suspension and progressive rate coil springs with 15 inches of travel allow the Unimog to tackle tough off-road terrain.
“The cab is constructed from high-strength, low-weight, composite fibers,” McTernan says. “It features comfortable seating for up to three occupants. The driver sits up high and has good views to all corners thanks to the flat-face, wide-view windows.”
One feature not commonly found on other vehicles is the Unimog’s optional VarioPilot system. “VarioPilot allows the operator to move the vehicle’s steering column and pedals as a complete unit from one side of the cab to the other,” McTernan says. “By simply throwing a lever, all truck controls can be shifted in less than 30 seconds. It’s perfect for driving to a jobsite, then shifting over so you can watch a curb or trench when using a blade or powered attachment on the front end.”
All told, a fully equipped Unimog will cost you from $90,000 to $100,000 minus any attachments. And although Unimog will custom build each truck ordered, some advance models began appearing at Unimog and Freightliner dealerships in January.