Four Decades Ago, This Goofy Aerodynamic Truck Was The Ford Taurus Of Semis

Aerodynamics is a huge deal in vehicle manufacturing today. Slipping through the air as easily as possible helps EVs attain high range and aids small cars in helping score incredible fuel economy numbers. Aero is also critically important in the trucking industry, where even small gains make a huge difference. Back in the 1980s, one semi-truck manufacturer placed an insane focus on aero. The Kenworth T600 was built from the ground up to slice through the atmosphere, and as a result, this classic semi ended up doing to the trucking industry what the Ford Taurus did to the car industry.

The original Ford Taurus was a huge deal when it launched in 1985 for the 1986 model year. The Taurus had been born in an era when most cars looked like blocks or wedges and had the coefficient of drag to show for it. However, as the world transitioned into the fuel economy-conscious 1980s, it was time to take radical steps to improve efficiency and style.

The Ford Taurus was a gamble. It was a futuristic car with computer-assisted design, a body shaped by wind tunnel testing, and an interior that matched the forward thinking that propelled the vehicle’s entire design. The soap bar-shaped Taurus was such a departure from what any of its competition was doing that, as the book Taurus: The Making Of The Car That Saved Ford by Eric Taub noted, people within Ford itself had doubts that the public would buy it. The fear was that Ford might have built a car too far ahead into the future. Apparently, Chrysler felt similarly.

Instead, the Taurus changed the game. The press couldn’t get enough of the Taurus. Car and Driver once said that the Taurus “Shapes the Future of the Family Sedan” and countless more recent retrospectives claim that the Taurus “revolutionized American car design” and saved Ford. These headlines aren’t wrong. Ford invested so much money into the Taurus that, had it failed, bankruptcy was a real possibility. Instead, the Taurus was such a sensation that those same skeptical automakers suddenly had to rush to put their own potato-shaped designs into production.

The Taurus was not the first car shaped by the wind. It even had contemporaries in the form of rounded Audis. Yet, its impact was huge. One could even argue that the effects of the original Taurus are still being felt today as the automotive industry continues to optimize its cars to an obsessive degree.

What’s not often told is that while the Ford Taurus was bringing aero to Detroit, a similar revolution was also happening in the trucking industry. Launched only a year before the Ford Taurus was the Kenworth T600.

On the surface, this conventional semi-truck doesn’t look all that impressive. We’ve had semis that looked like this for decades! But have you ever thought about when more aerodynamic designs became more popular? Trucking’s “Ford Taurus” moment is often regarded to be when the Kenworth T600 hit the road, promising to make trucking more efficient and futuristic.

Truckers Battle The Oil Crisis

This story takes us back to the 1970s, a decade that car enthusiasts identify with monumental change in the auto industry. The Oil Crisis of 1973 brought on a greater focus on fuel economy and downsizing. This was the era that is remembered for the infamous “double nickel” 55 mph national speed limit. At the same time, Americans were getting serious about car safety and pollution from vehicle emissions. All of these and more began reshaping the cars that we drove. Add in a poor economy and fading confidence in the government because of war and scandals, and you have what we now call the Malaise Era.

Trucking was facing some of the same issues that cars were. As Today’s Trucking wrote in 2005, diesel prices skyrocketed in the wake of the oil crisis. This threw a wrench into the works of the trucking industry. The shipping of so many critical goods depends on trucking, and rising fuel prices can kneecap the industry.

Today’s Trucking reminds us that in 1976, Kenworth engineer Larry Orr sought to bring the trucking industry into the future. If fuel prices couldn’t be lowered, maybe the truck itself could be the solution to high operating costs. For reference, according to a 2008 U.S. Energy Information Administration report, the price of diesel was $0.36 per gallon in 1978, skyrocketing to $0.97 by 1981, or a 170 percent increase.

Aerodynamics weren’t exactly the main focus of truck design at the time. The 1970s were at the tail end of the cabover semi era, where truck cabs were situated over the engines and front axles. Cabover semis remain some of the coolest big rigs in American trucking history. They also complied with the length restrictions of the era. However, cabovers were basically bricks pushing a load through the wind.

Meanwhile, conventional semis, or trucks with a front axle and engine ahead of the driver, with a corresponding “long nose,” were also a popular option. One of Kenworth’s most iconic designs, the W900 (above), was introduced in 1963. Here’s a little bit of history about that truck from Kenworth:

The W900 is one of the most iconic trucks in North America’s trucking history, known for its classic long hood, conventional design, rugged durability, and driver-focused comfort and style. Since the W900’s introduction in 1963, it quickly became a favorite among owner operators and fleet drivers. The W900’s versatility and customizable platform made it a reliable choice for long-haul, heavy-haul, logging, dump, and other vocational and on-highway applications. Since the W900’s inception, Kenworth has incorporated advancements in technology, styling, and performance into four iterations that have proven essential for different jobs while maintaining the iconic look. The W900A provided improved cooling for optimal engine operation, the W900B debuted with a cab update and additional cooling innovations, the W900S was designed for ready mixed concrete-specific applications, and W900L brought a long-hood variation for performance and appearance.

“The W900 is truly historic in that it’s helped shape North American trucking culture and tradition as we know it today,” said [Kevin Haygood, Kenworth’s assistant general manager for sales and marketing.] “Often seen at truck shows, featured in movies and on TV, and shown at other events, it’s an iconic truck that’s cherished for its classic styling by our customers and truck aficionados. While production of these trucks is coming to an end, we look forward to seeing them on our roads and at truck shows for many years to come.”

Yes, incredibly, the W900 is still in production today and will finally haul into the sunset in 2026. The W900 has been in production for so long that its last generational overhaul was in 1982. Because of the insane longevity of a Class 8 truck, it’s possible we’ll still see W900s on the road for decades to come.

The inclusion of the W900 into this story is important because this truck would form the platform of Kenworth’s moonshot aero truck.

The Kenworth T600

As Today’s Trucking reported, Kenworth’s solution to high fuel prices was a dramatic increase in semi-tractor efficiency. That meant finally doing something about aero. At the time, Kenworth claimed that 75 percent of a semi-truck’s aerodynamic drag was caused by the tractor’s front profile alone. Weirdly, the T600 project started off by trying to make a smooth cabover truck. This might sound silly, but 55-foot overall length restrictions were still in place when development began, so it made sense to make the aero truck out of a popular cabover.

The Motor Carrier Act of 1980 helped advance a process of trucking deregulation, which resulted in more trucking companies entering the market. Then, the Surface Transportation Assistance Act of 1982 helped establish national standards for semi-tractor lengths. As Today’s Trucking notes, deregulation in the early 1980s marked the end of the cabover semi-tractor’s reign in America. Previously, the cabover was dominant, but that was largely due to length regulations. Now, more comfortable conventional tractors were poised to take over.

This also meant that Kenworth had to shift gears to keep up with the times. The great thing was that Kenworth already had a dependable and popular convention in production with the W900, so Kenworth engineers turned their eyes to that rig.

Today’s Trucking notes that, early on, Kenworth engineers tested their aero theories out by building wood and clay models and taking them into the wind tunnel at the University of Washington. There, these models proved their idea to be sound. If you make a truck that’s a lot less of a brick, you can get notable gains in fuel efficiency, which can help a trucker deal with high fuel prices.

By the early 1980s, Trucknews.com writes, the engineers at Kenworth graduated from the models to a full-size working prototype. This truck validated the engineers’ theory about aero, and now it was time to make the truck a reality.

Kenworth notes that while the T600 is based on the W900’s architecture, the rest of the truck was built from the ground up around aerodynamics. There had been other trucks with some form of aerodynamic smoothing, but nobody had gone to the obsessive level that Kenworth engineers were going through on the T600. One prominent feature of the T600 design is its sloped and rounded hood, itself a massive departure from the flat and blocky hoods of the past. Another easy change to point out is the flush headlights and swept integrated fenders. The cab is also smoothed out as much as possible.

But there’s way more going on under the skin. The truck’s diesel tanks, air filter, and batteries, which are normally proudly on display on a typical conventional truck, were placed behind body panels for further streamlining. Even the front bumper has some trickery going on with a polyurethane air dam to help redirect the air that goes under the chassis. Further changes come in the form of a spoiler on the truck’s roof that adjusts to different trailer heights and cab extensions that close the open gap between the cab and trailer. Finally, Kenworth engineers also added low-profile tires and an efficient drivetrain.

Kenworth figured an aerodynamic truck didn’t need as much power to haul, and the powertrain reflected this. There were a ton of drivetrain configurations sold, so I’ll just give a couple. I’ve seen some old T600s equipped with 300 HP Cummins L10 10-liter straight-six diesels. I’ve also seen older T600s with 365 HP Cummins Big Cam IV 14-liter straight-sixes. I’ve also seen T600s with 9-speed and 13-speed manuals.

There were platform improvements, too. T600s have a front axle that’s set further back than the typical conventional. The change to the axle, with its accompanying change to longer 64-inch taper-leaf front springs, improved both ride quality and axle weight distribution. Other improvements to be seen and felt behind the wheel were better visibility from the low hood and better maneuverability from a turn radius that was 23 percent sharper than other conventionals of the era.

All of this added up to a truck that proved to be phenomenal in real-life usage. Kenworth found out that its drastic streamlining and efficient drivetrains resulted in a 22 percent increase in fuel efficiency. That’s incredible! In practice, this meant that a T600 truck got around 9 mpg in an era when other conventionals might have gotten 7 mpg or 7.5 mpg. A whopping 2 mpg doesn’t sound like much, but you have to consider that these trucks are putting down hundreds of thousands of miles, so a change of even 1.5 mpg makes a huge difference.

Kenworth was smart with the T600’s marketing. The company knew that the T600 wasn’t exactly a looker. Truckers were used to huge engines, miles of chrome, and tall stacks. Kenworth was now asking them to buy a truck that, to some, looked like an anteater.

Today’s Trucking notes how some reacted upon seeing the new truck:

Most of this was lost on the old-school crowd at the Fifth Wheel, who, as intrigued as they were, thought hoods should be straight and broad and the longer the better. In fact, 38-year Kenworth veteran Wayne Simons, who was engineering manager at the time and much involved in the T600 project, remembers those comments only too well. Even some KW insiders weren’t terribly sure about its looks, he says. On a fuel-test run in 1985, he remembers so many insults that he had to turn the CB off.

“We heard comments on the CB all the way from Arizona to Florida,” he says.

But no one inside Kenworth doubted the new truck’s ability to save fuel, so the company was pretty sure it had a winner on its hands.

Ouch. You can only imagine the insults thrown through the CB. Kenworth knew it couldn’t just show a truck off to truckers and expect it to sell. Instead, it put those skeptical truckers behind the wheel. Sure, they might not have liked how it looked, but could they resist the fuel economy?

The Ford Taurus Of Big Rigs

The answer was a resounding no, because when the T600A launched in 1984, truckers and fleets began scooping them up en masse. By 1985, Kenworth says, the T600 accounted for a full 50 percent of Kenworth’s sales. The anteater was a winner. By the 1990s, Kenworth gave the T600 a streamlined sibling with the T800, and together, the trucks dominated Kenworth’s sales charts.

Then, something interesting happened. It’s hard to ignore when a single model is so popular that it accounts for half of a manufacturer’s sales. Other truck manufacturers took note, and just like with the Ford Taurus, they also responded by building newer, sleeker rigs with greater efficiency.

You can see this influence even in rigs like the Freightliner FLD120 and others. The old and blocky trucks still remain legends, but truck manufacturers also offer futuristic, slick big rigs.

By 1994, the impact of the T600 on the trucking industry became clear, and in response, Kenworth won the U.S. Department of Transportation’s National Award for the Advancement of Motor Vehicle Research and Development. Even the government thought the truck was that much of a leap forward. By 2005, the T600 was such a huge success that Kenworth sold over 108,000 units over 20 years.

The T600 Lives On

The T600 bowed out in 2007, but its legacy can be found everywhere. Kenworth followed the T600 up with the even sleeker T660, and as I noted earlier, aerodynamics have become a big deal in the trucking industry. Now, you can see all kinds of neat aero tricks out there from smooth wheel covers to weird trailer tails. I mean, just look at the Tesla Semi’s entire front profile.

For many, a lot of this aero obsession can trace back to the T600. As I said earlier, it was far from the first aero truck–the trucks and buses of decades prior also experimented with streamlining–but Kenworth took it to a new level.

So, the next time you see an old Kenworth that looks like an anteater, now you know that weird-looking truck is way more important than it seems. What’s the value of 1.5 mpg? Apparently, the answer can be the development of an entirely new vehicle.