COE is short for Cabin Over Engine, and it is a common colloquial designation for trucks with such architecture. They are not exactly an everyday sight on the roads but for some of us, non-trucker people mostly, the roads seem to be missing something without them. Some time ago – especially in the Seventies – American roads were flooded with COE trucks. Everyone produced them, but the most outstanding units usually come with the Freightliner, Mack, or GMC plaque. Nowadays, we just don’t see them. Almost all of them have been replaced with the classic truck design. True, only a handful of special-purpose COE trucks remain (fire department and dump trucks for example) on the roads.
Why did COE trucks disappear from American roads?
First of all, they had emerged as the preferred solution on the East Coast even before WWII, when regulations limited the maximum length of the truck with a trailer. This meant that manufacturers had to find a way to squeeze every cubic inch of cargo capacity to use. Apparently, shortening the cab was the preferred solution. Truck cabins became smaller and smaller cutting down on driver comfort while giving more space for the trailer and cargo.
Everything changed in 1982 when new regulations marked that the only limiting factor was the length of the trailer (53’). Obviously, truck manufacturers rushed to make the cabs more comfortable and engines more powerful to offer all the more appealing package. COE truck design simply was not optimal anymore. This marked the dawn of the new age for the American trucking industry. However, in Europe, Australia, and China, COE trucks are the only option as manufacturers have to be compliant with the strict length regulations.
Nevertheless, aside from the regulations, COE trucks have many disadvantages compared to conventional truck design. Click next to view our list of 7 reasons:
1. Sleeping Nook Size and Driver Comfort
One of the biggest disadvantages of COE trucks was limited space in the cabin. Just think about it, manufacturers had to cramp all of the driver necessities to provide as much space for the trailer as possible. As a result, the driver was really close to the windshield, the sleeper bunk was rather cramped and the personal driver cargo space wasn’t as plentiful as in conventionally built trucks. Do not think for a second that this is nitpicking. Truck drivers have to cover incredible mileage per year sometimes being on the roads for days. Having a comfortable cabin is one of the most important features of any modern truck. The problem became evident in the Sixties and Seventies with the development of the national highway system. Trucks started to cover extreme distances rather fast. Necessities for the comfort in cabin became more important than ever.
Modern “conventionally” designed trucks have an exceptionally well-crafted cabin accommodating one or two sleeper bunks and, depending on the version, offering accessories such as a microwave, TV, fridge, head and other.
2. Noise Levels
While comfort was one of the main issues for COE trucks, noise was high on the list too. As the engine is basically right underneath the cabin and under the driver, it was not easy to isolate the cabin from the rattles and noises that the massive petrol or diesel engines were unleashing. Just imagine how excruciating it would be to drive thousands of miles with the engine sounds and vibrations constantly bombarding the entire cabin. It is not exactly a pleasant experience.
Nevertheless, modern European COE trucks actually do have rather pleasantly equipped cabins, are exceptionally well isolated from the engine and the road and, I am sure, are every bit ergonomically sound as American trucks.
Reading about this topic, I came across a number of testimonials from drivers of the old COE trucks and it seems that back then, the driver was at the second or third place on the “importance chart” for the manufacturers.
Jim Park of truckinginfo wrote this:
“Having gone from that 1969 Freightliner to a 2016 Cascadia, I can say unequivocally, drivers have it better today than when I started. I maintain my fondness for the Mack R-Model, the International Transtar and the Pete 359, but if faced with weeks on end in any of the trucks listed above, I’d be mighty happy to be handed the keys to anything built in the last few years over what I drove during the first 20 years of my time in trucking.”
Obviously he wasn’t just referring to COE trucks, but you get the picture.
3. Maintenance and Repair
One of the most important disadvantages of COE trucks was all the hassle associated with the maintenance and repair of the engine. Conventionally built trucks have their engines in a special, separate engine compartment at the front giving mechanics exceptional access to the engine and all of the crucial systems.
While the COE trucks do offer optimal access to main engine components, this is achieved by tilting the cabin. So, before actually doing it, the driver has to fasten and secure all of the loose items in the cabin sometimes making the process rather time-consuming and arduous. Plus, the process of getting in the cabin is far more challenging than in any of the conventional trucks. All in all, having a conventional truck will give you better access to the cabin, better access to the engine and all of the systems associated with it, as well a lot more room between the axles to store necessary accessories. Higher capacity fuel tanks, hydraulic tanks, utility boxes for chains and binders will have their own dedicated places. The longer conventional truck design definitely has its advantages.
Back in the Sixties, Seventies and Eighties, trucks (or cars), simply did not have all of the advanced safety systems as today. No sensors, no radars, no 3D scanning cameras, no ABS, no stability programs, no hill descent control or anything remotely similar to it. So, while the best trucks of today (COE or conventional) do have superior safety compared to basically anything on the roads, COE trucks of before didn’t. There was a running gag among the drivers of COE trucks.
“Who is the first person at the scene of the accident?”
- “The driver!”
As the driver is basically only two feet behind the windshield any head-on collision may prove fatal. No engine block to protect you, or any other “real estate” to absorb the impact. Conventional trucks, of course, do provide superior safety measures. I have to point out that European COE trucks of today do offer exceptional active and passive safety features making them practically as safe as American conventional trucks.
5. COE Trucks are More Difficult to Produce Than Conventional Models
Designing, adopting production facilities for and manufacturing conventional trucks is somewhat less complicated compared to the production of the typical COE truck.
The engineers have a lot less space to work with when designing the COE truck. Having less space to do the same task as the engineers of the conventional trucks, they usually need a lot more time and have to master far more issues before production.
You can see the problem.
Massive engineering challenges have to be tackled which usually raises the investment a company has to make to develop a truck. As the regular truck isn’t as compact and cramped, engineers have fewer problems placing all the necessities and don’t have nearly as many problems to solve as far as space-saving is concerned.
6. Conventional Trucks can Haul Bigger Loads
This is definitely one of the most important features of the conventional truck style. More powerful engines usually mean that the rig is better equipped for hauling bigger loads. As the regulations do limit the length of the trailer, they do not regulate the length of the whole mobile asset. This means that one truck can haul multiple trailers.
For example, European regulations do permit the maximum length of the mobile asset thus limiting the necessity for extremely heavy loads. Nevertheless, another factor plays a crucial role: physics. Conventional trucks do have a longer wheelbase and while this affects the maneuverability and the turning circle (rather dramatically), it also enables engineers to engineer a truck which can safely haul bigger loads. The truck is more stable on the highway and can distribute the mass more effectively.
7. Short Wheelbase Designs aren’t Optimized for Highways
Short wheelbase designs simply aren’t perfect for high-speed highway runs. While COE trucks are definitely far more maneuverable and are perfect for tight places (like city driving), conventionally styled trucks are simply better for the highway. Stability is a key factor here, especially under heavy loads. Plus, a longer wheelbase offers far greater comfort for the driver as the captain’s chair placement isn’t on top of the front axle but in between the axles. Now, some may argue that COE trucks do offer superior visibility, but it seems that that is not enough to convince drivers or fleet owners to invest in them.
Apart from highway stability, a long wheelbase conventional truck with rugged architecture is better suited for rough terrain. When considering construction usage, a sturdier truck is always the best option.