Wörth am Rhein, Germany - When my wife, Victoria, asked me to help plan our dream European vacation, she didn't think we'd be spending an entire day at a truck factory. But that is what's on the docket for our second day in Germany.
To be fair, this isn't just any truck factory. This is the Mercedes-Benz Special Trucks assembly line. This is the line that produces some of the most capable off-road vehicles in the world. This is the line that builds one of the most storied, significant nameplates in the Mercedes-Benz portfolio.
This is the home of the Mercedes-Benz Unimog.
Unimogs might be classified as medium-duty trucks, but dismissing them as simply big trucks is like brushing off da Vinci as "some painter." Each Unimog is handbuilt, like an AMG engine. Each truck packs perhaps more technology than an S-class -- but don't look for a hot-stone massaging seat. And depending on what options are selected at the factory, a Unimog might look more like a tractor, a train, or a tank than anything you'd consider to be a truck.
A quick stroll through the Unimog Museum, located near the plant in Gaggenau that built Unimogs for more than fifty years, gives us a good idea of how versatile this Mercedes truly is. We're surrounded by 'Mogs of all ages, shapes, and sizes, each equipped for different tasks. Farming, fire-fighting, forestry, snowblowing, wood chipping, rally racing -- the possibilities are seemingly endless. Hans-Jürgen Wischhof, who ran the Unimog division from 1990 through 2003 and now serves as a consultant to the museum, tells us "the Unimog can do anything but fly or swim."
Once upon a time, the Unimog's purpose was rather simple. Although the Morgenthau Plan was never fully implemented after World War II, its proposal to transform Germany into an agrarian state resonated with Albert Friedrich, an aircraft engineer working at Daimler-Benz. Friedrich envisioned that Germans would need a versatile agricultural machine with seating for two, four-wheel drive, ample cargo room, a trailer hitch, and a mounting point for powered attachments that could be used on the farm. Portal axles, which place the wheel hubs below the actual axle shafts, were considered essential because they increased ground clearance -- a key element when driving in a plowed field.
After convincing Allied authorities that he wasn't building a military vehicle, Friedrich and his team of engineers produced the first Universalmotorgerät, or "universal motor vehicle," in late 1946. The first production models, built by the Boehringer machine shop, rolled off the line in 1948, but by 1950 Daimler had purchased the production rights and moved Unimog assembly to its own facility in Gaggenau. Shortly after, the Unimog lineup split in two: a smaller, multipurpose model sold to farmers, municipalities, and industries; and a larger model that catered to cus- tomers -- often foreign military powers -- seeking a vehicle with unrivaled off-road capabilities.
That dualistic model line continues today. The Unimog U4000 and U5000, derived from the models launched nearly forty years ago, are known as the "off-roaders" and boast extreme approach and departure angles plus ground clearance that makes a G-class seem like a lowrider. The Unimog U300, U400, and U500 are considered the "implement carrier" models and are aimed at municipalities, utility companies, farmers, and so on. These trucks can have up to four implement-attachment points, three PTOs (power-takeoff shafts), powerful hydraulic circuits, and insane 24-speed semiautomatic transmissions complete with fold-away clutch pedals.
Of course, the implement carriers still retain the hallowed portal axles, locking differentials, and massive ground clearance. As Wischhof says, "No one will buy a Unimog if he or she cannot have that off-road capability."
The models share a common assembly line in Wörth -- which, in turn, is shared with two other uncommon Mercedes-Benz trucks: the low-entry Econic cabover, and the massive Zetros off-road truck. All three trucks are assembled in Building 20, which Daimler calls the "factory within the factory." The plant at large employs some 12,000 workers, but only 865 are assigned to the Special Trucks line, and only after they've completed a yearlong training program on top of their normal three-year apprenticeship. Basic cab structures and engines are shipped in from elsewhere, but every other part of a Unimog is hand-assembled at the facility.
We arrive at the assembly line during a transition period: not only has production of the new Euro 6-compliant models begun in earnest, but some of the very last cab-forward U20 models -- which are being discontinued after the 2013 model year -- are also moving slowly down the line. After walking along the entire production line, we head to the back of the property. Nestled between a storage lot for recently assembled trucks and a finger of the Rhine River is the Piglet, a small off-road course used for customer demonstrations. We're ogling the terrain when a silver U4000 cargo hauler whips around a corner and stops in front of us. It's time for a quick ride.
The truck has two doors, but there are also two passenger seats. Victoria and I climb some three and a half feet into the cab. The cab is six and a half feet wide, but as the middleman, I'm brushing shoulders with both the driver and my wife.
"You're in good hands," our guide tells us. "Your driver, an employee on the Unimog line, vacations at Dakar."
"Oh, he visits Senegal?"
"No," we're told. "He uses vacation days to compete in the Dakar Rally."
We make our way slowly around the soupy stomping grounds, the Unimog's 4.8-liter, four-cylinder turbo-diesel clattering loudly against the subtle whine of the gearbox. A little knob on the dashboard, to the right of the gauge cluster, commands the four-wheel drive. Click it one stop, and the center differential locks, turning a rear-wheel-drive 'Mog into a four-wheel-drive vehicle. Crank it to the next stop, and the rear differential locks, splitting power evenly between both rear wheels. Dial it to the fourth position, and the same effect is applied to the front wheels.
For most of our brief romp, the U4000 is kept in four-wheel drive, but our driver rarely -- if ever -- uses the other diff locks as we crawl our way around the sloppy course. He nudges the passenger side of the truck up an embankment next to the path, demonstrating the Unimog's ability to travel on 38-degree side slopes -- and, for that matter, the usefulness of the ceiling-mounted "Oh, Scheiße!" handle above my head, which you can grab when you're trying to avoid crushing the person seated next to you. Crawler gears allow us to creep slowly down a steep embankment, leaving us hanging in our seatbelts like giant marionettes.
This track takes advantage of only a fraction of the Unimog's abilities; the truck isn't even breathing hard. Victoria and I, however, are laughing hysterically. Our driver, who speaks little English, interprets this as a sign to increase our pace sevenfold, especially over a series of jumps that wouldn't be out of place on a motocross track. The ride isn't rough, but the frequent change in both yaw and pitch means it's a good thing we're going through these motions before eating lunch.
Interestingly, there's one piece of land the Unimog has trouble tackling: North America. Although off-road enthusiasts have independently imported vintage models, official attempts at selling the Unimog in the United States and Canada have been spotty, at best. J. I. Case sold Unimogs as agricultural machines from 1975 to 1980, and a handful of independent importers hawked Unimogs in the States after Case washed its hands of the machine. Daimler itself gave it a try in 2003, selling the then-new U500 through select Freightliner dealers in North America. Citing upcoming changes in emissions standards, it withdrew the U500 from the market in 2007, having sold no more than 200 U.S.-spec 'Mogs.
"We didn't exactly have the success we wanted in America," admits Wulf Aurich, product manager for the Unimog line. "The truck is ideal for the confines of European cities. In the States, operators can use big trucks, big trailers, big machines, multiple machines, and it's not a big deal. Here in Germany, an operator or agency will have one garage, and there's no room for multiple pieces of equipment. They do, however, have room for one Unimog and a range of attachments."
Emissions compliance poses a bigger headache for the Unimog. Aurich says refederalizing the U500 wouldn't be too difficult since most of the work has already been done, but certifying the Unimog's diesel engine to North American EPA standards would cost millions. As volumes would be well below 100 trucks annually, there's no chance Daimler could amortize the development cost.
"I can't predict the future of the Unimog in the U.S.," Aurich continues. "But so long as there's no common emissions standards, I think the last U.S.-spec U500 will be the last new Unimog for America."
As far as Aurich is concerned, the Unimog's future isn't in North America but in efficient powertrains and efficient packaging. "Customers are always asking for a smaller Unimog," he says. "There's always lots of work to do on walkways, pathways, and so on, but on the other hand, we can't add complexity to the product. Likewise, we need to look at transitioning the diesel driveline to something else. Natural gas? Electric? A mixture of the two? It's a question we will need to face."
Since Daimler is in the process of launching a new family of Unimogs, these dreams are still some way off. "We have a new product family, and its life cycle should be ten to fifteen years," Aurich points out. "We don't know what customers will be asking for at that point."
Perhaps not -- but I do know when I'll be talking to Victoria about a return trip to Wörth am Rhein . . .
How Can I Use A Unimog?
- Compete in a desert rally
- Rescue a stranded commuter train
- Tend fields
- Fight fires
- Clear snow
- A night at the opera