Radial truck tires have come a long way in the last several decades. Initial tread
mileage, resistance to irregular wear, fuel efficiency and casing durability/retreadability are some of the major areas of advancement.
Over the long haul, gains in tire technology are impressive, but progress is historically slow and methodical, evolutionary in nature and not especially exciting in the short term. This same analysis applies to many other commercial vehicle components, including major sub-assemblies. There is little change until the cost/benefit is fully understood and accepted.
Compare the dollar-driven snail’s pace of truck technology to the recent explosion of new vehicles, packaging configurations and powertrain variations in the automotive and light truck fields. New technology is rampant and on high-profile display, and the competition is intense.
The hardware on display at the North American International Auto Show in Detroit earlier this year was enough to impress even the most laid-back industry watcher. It wasn’t all about style and sheet metal, either. New engines, drive line and suspension components, efficiency enhancing electronics, and alternative powertrains were all on display.
Particularly interesting were the alternative fuel engines and hybrid vehicles. These hybrids are no longer flash-in-the-pan eccentric technologies meant to impress life-long Sierra Club member. Rather, they are well-evolved usable vehicles. In fact, one production hybrid, which combines a traditional gasoline engine with a regenerative electric propulsion system, was chosen as the North American Car of the Year.
It is reasonable to think that the amount of investment in these programs, by companies notorious for their concerns about marketshare and cash flow, reflect some clearly defined goals and are driven by consumer desire.
A quick look around parking lots of most suburban shopping centers reveals a dazzling array of new vehicle configurations ®“ many of these designs are new ®“ debuting within the last two years. The sheer number and extent of the changes in auto and light truck offerings is almost bewildering.
At the same time, commercial trucks continue to evolve at a much slower and methodical pace.
The reasoned explanation for this has traditionally been that function, life-cycle costs and operating efficiency are the primary factors driving (no puns here!) buyers of these vehicles. On the consumer side, non-economic factors like style, perception and emotion rank high in the purchase decision process.
I wonder, though, if some of these newly emerging technologies (beyond styling and superficial repackaging) will find its way to the commercial market to deliver tangible operating benefits.
Consider the energy efficiency possibilities, for example. For years, a rule of thumb for internal combustion engines has been that for the latent heat content of fuel fed to the engine, approximately one-third resulted in usable power to the drive train, one-third left through the exhaust as heat and one-third was lost as heat through the cooling system.
Turbocharging, inter-cooling, electronic fuel delivery controls and higher operating temperatures have helped to skew this mix in favor of more usable power. But this “system” is still open to lots of efficiency improvement. Energy is also lost in the form of heat whenever brakes are used. Capturing and harnessing this ®lost® energy is the basic concept of current generation hybrid autos. Batteries and auxiliary electric motors are used to accomplish this.
With the exception of some specialized European coach designs, such systems are rarely seen on truck or bus chassis. Added weight and mechanical complexity limit their use on commercial vehicles versus autos. But efficiency improvements have now become a high priority among commercial truck users, so technology advances will soon wipe away those weight and complexity issues.
If and when truck manufacturers consider hybrid powertrain designs, several North American configurations would seem to be good candidates.
First, the basic 18-wheeler could become a cargo container chassis, with all axle ends driven by auxiliary electric motors to the extent that stored power is available. Secondly, delivery and pick-up vehicles (e.g. waste haulers) especially could benefit, due to the high frequency and severity of braking and resulting energy available for regeneration.
Other applications, such as short wheelbase doubles/triples and tractors could become all-wheel drive, resulting in improved traction, handling and efficiency. The electric drive components could be used to supplement traditional power transfer systems or as primary drive components placed on each driven axle, with energy supplied by a combination of engine- and brake-generated power.
Basic changes of this magnitude would, of course, require major rework of current designs. Trailer manufacturers would have to integrate their designs with truck/tractor manufacturers. Other components, including tires, brakes and electrical systems, would likely change considerably from the current axle-specific designs as driving, braking and cornering forces would tend to converge.
It sounds complex, challenging and possible. Given the talent available in our industry, it just might happen ®“ if the rewards are there in the form of efficiency and operating costs.
We’re a long way from hybrid Peterbilts or Freightliners. Even without wholesale changes, though, we will continue to see further efforts to improve vehicle ®“ especially tire ®“ fuel efficiency at all wheel positions.
With tire raw material costs escalating higher and faster, casing durability and removal mileage will become more and more important to cost-conscious fleets. Engine performance ®“ fuel economy ®“ will also take center stage as fleets and owner-operators face ever higher diesel prices.
So, even though we won’t likely see alternate energy 18-wheelers anytime soon, growing cost and competitive pressures will press faster integration of new technology in the commercial sector. It may not be as dazzling as the technology on display at the auto show, but it will be considerably more effective.