Cab-over, also known as COE (Cab Over Engine), cab forward, or forward control, is a body style of truck or van that has a vertical front or "flat face", with the cab of the truck sitting above the front axle. This truck configuration is currently common among European and Japanese truck manufacturers, because the laws governing overall vehicle lengths are strict and the body style allows longer trailers or a longer cargo area for the same overall length.

Although popular among United States heavy truckers and trucking companies during the 1970s because of strict length laws in many states, in the U.S. most heavy trucks use other body styles. It is however still very popular in the light and medium truck segment, such as the Isuzu NPR series. Most Japanese minivans like the Suzuki Carry, Toyota Hiace and Mitsubishi Delica also utilize this body layout. It was also used for the (rear engined) Volkswagen Type 2 van, and in military vehicles such as the Land Rover 101 Forward Control and the Pinzgauer High Mobility All-Terrain Vehicle.

History

The Sternberg company of Wisconsin produced cab-over trucks as early as 1907, though by 1914 only their seven-ton model was a cab-over. They reintroduced the cab-over layout in 1933 with their "Camel Back" model, which allowed the cab to be tilted to access the engine.

The introduction of the first modern cab-over layout in the U.S. is credited to industrial designer Viktor Schreckengost, who with engineer Ray Spiller designed a cab-over truck for the White Motor Company in 1932.

The laws of the time limited truck length to on highways. Siting the cab over the engine saved several feet of cab length, which was added to the trailer capacity. Schreckengost patented the design in 1934.

White-Freightliner introduced the first tilting cab-over design in 1958, which allowed the entire cab to tilt forward for access to the engine.

Advantages

The cab-over design makes the vehicle's wheelbase shorter than the conventional arrangement with a long horizontal hood and the engine placed in front of the cab. This shorter wheelbase allows semi truck to have an overall shorter length allowing for longer trailer to be used, or it means rigid vehicles can have a longer load area. The shorter wheelbase also gives the COE an advantage in maneuverability over a conventional model. And since COEs are lighter than conventionals, they can theoretically haul heavier loads. Despite the COE designs being smaller in general, they can still be fully equipped with single or bunk beds. Also, lack of a hood gives better visibility to the driver and significantly reduces the forward blind spots.

Disadvantages

Some drivers have complained, however, that the shorter wheelbase in the COE trucks gives a rougher ride than those with conventional cabs, as the driver's seat is above the front axle; and that the cabs tend to be noisier because the engine is directly below.

Because of its flat front design, a COE truck has significantly worse aerodynamics than a conventional tractor. This causes a loss in fuel economy, and handling during highway speeds.

Although the tilting cab gives comparatively unobstructed access to the engine, its deployment causes unsecured items in the cab and sleeper (if equipped) to fall onto the windshield.

Also, the lack of a safe crush zone in the front makes it far more dangerous in the event of a crash.

See also

• Cab forward
• Jeep Forward Control
• Ford C-Series

Notes

1. Richards Award Winning Kenworth Cabover

References