Technology in Class-6 to Class-8 vocational trucks tends to evolve at a moderate pace. But exhaust emissions and fuel-efficiency regulations have accelerated the rate of technology adoption that is expected to transform truck offerings in the medium- and heavy-duty market in a relatively short ten years.

"We will see an increase in alternative fuels with no revolutionary technology in the next five to ten years" says Len Deluca, director, Ford Commercial Trucks. The company's strategy is to offer choices. "One technology may work for one customer, but doesn't work for another. There is no silver bullet. Ford believes alternative fuel selection is the future. It will all depend on the application and what the customer needs. Diesel engines will continue to be the predominant engine."

In addition, gasoline engines may start making headway in the medium-duty market. "We foresee an opportunity with our upcoming 2012 F-650 truck with a 6.8-liter V10 gas engine," says Deluca. "There are many advantages that a gas engine has over a diesel engine, in particular, acquisition price. It will give customers who don't need the full capability of a diesel powertrain a more economical purchase option."

Focus on fuel

Fuel economy is always top of mind for commercial truck owners. "It is the biggest operational expense for many customers," says Deluca. "Ford expects the cost of diesel will continue to increase in the future."

The upcoming heavy truck fuel economy standards will impact vocational truck offerings."The new fuel economy standards will mean a higher acquisition price, but it should be offset by reduced fuel costs over the life of the truck," says Deluca. "Customers should also expect more alternative fuel choices offered by manufacturers to help offset rising diesel costs."

"The 2014 Greenhouse Gas (GHC) regulations will make both OEMs and customers look at fuel economy from a broader perspective than in years past," agrees Brad Williamson, manager, engine and component marketing, Daimler Trucks North America (DTNA). "But this will not change our direction to always provide innovative products that are both good for the environment and our customers' bottom line. Many changes (for both engine and truck technology) will be moderate in pace with a constant focus to improve on what we can offer today, yet still keeping our eyes open for potential developments that could accelerate the pace of change."

It all centers around fuel efficiency. "We will continue to work to get more fuel economy," says Bob Mann, Navistar. "Fuel economy is tremendously important for every application."

Vocational trucks will need to take a much different approach than over-the-road tractors. "In the vocational world, there are not a lot of things we can do with aerodynamics," says Mann. Instead, much of the focus will revolve around certain truck accessories. "Today, a lot of those are basically driven off the engine. We are going to be looking at other ways to [drive them]."

Engines have limitations on how much economy you can extract. "If you want to get a certain amount of horsepower out, you are still going to have to put a certain amount of fuel in," notes Mann. "We are already running two turbochargers. We already have high-cylinder injection pressure. It is going to have to come in some other ways than just the engine." Some of the possibilities include reduced driveline friction, different gear ratios and methods to power accessories on the truck without the engine running.

Recent changes in the vocational truck market have really been driven by government regulation and aren't directly tied to customers' bottom lines. That said, OEMs are working to ensure a return on investment.

"The changes that DTNA is working on benefit the customer, and this means an acceptable payback period for any equipment price increases," says Williamson. Many of the demands for off-highway trucks are the same as on highway: fuel economy, weight, durability and uptime. "DTNA is working closely with our partners (internal and external) to evaluate all options for new components to ensure the finished products we produce meet the customers' needs, promote the cleanest technologies available and position us for long-term success."