For the first time, heavy- and medium-duty trucks will have to reach government-mandated fuel economy standards starting in 2014. Those standards will become even more stringent by 2018. What will this mean to fleets? Most likely it will limit the number of components truck buyers will be able to specify in the future, which can be viewed both positively and negatively, according to industry experts.
There are a number of options currently available, sources say, from technologies to training and monitoring that can positively influence fuel economy now, even before the new models hit. Some of those technologies that impact driver behavior, such as idle and speed limiters, will become the law for many commercial vehicles in the future.
The greenhouse gas emissions 2014 (GHG14) standards were developed jointly by the National Highway Traffic Safety Administration (NHTSA) and the Environmental Protection Agency (EPA), along with input from the National Academy of Sciences, the trucking industry, environmental groups, and state governments. Vehicles will be required to achieve from 9 to 23% improvement in fuel consumption and GHG emissions cuts by model year 2018, saving up to 4 gals. of fuel for every 100 mi. traveled. EPA believes that through the new GHG14 regulations, trucks and buses built in 2014 through 2018 will reduce oil consumption by 530 million barrels and greenhouse gas emissions by 270 million metric tons.
EPA has developed a computer model that requires input from vehicle specifications, including aerodynamics, tires, speed limiters, and automatic engine shutdown, to limit idling in an effort to estimate a truck’s carbon dioxide emissions. By limiting fuel economy technologies to only those categories, it forces vehicle suppliers into a very small, tight box in terms of vehicle specifications and stifles creativity when it comes to improving fuel mileage, says Jim Hebe, executive vice president, North American sales operations, for Navistar.
Hebe says the “creeping socialism” in the current truck regulatory environment “leads to conformity and limits creativity.” And the devil in the detail is the ability of fleets to make creative specification choices. “Regulations are driving us into the same little box with emissions, and now are driving us into a narrow box in terms of spec’ing components to meet a fuel economy standard and hope in the process the truck will look good and still perform,” he says.
Hebe adds that all truck manufacturers will be able to meet the fuel economy standards, but wonders at what cost to customer satisfaction. “We can all meet [the standards], but what restrictions in options are you going to impose on your customer? Once you’ve certified what you offer in a particular vehicle category, you can’t change it.”
In order to meet the first round of fuel-mileage standards, some over-the-road tractors will most likely require automatic engine shutdown to limit idling, speed limiters to set maximum speed of the truck, and low rolling-resistant tires.
Idle managment
“Idle time becomes a very critical part of us establishing fuel economy standards,” Hebe says, but the EPA has yet to set the idle standard. “We as a manufacturer will have to establish idle time, and the customer will not be able to change it throughout the first use of the truck.
“There is nothing that we are going to do to the truck that we weren’t going to do anyway. It’s just that regulations limit us in what we are able to do and how we do it,” he adds. For example, Hebe says only certain tires will be certified for certain uses.
Suppliers are also confused by the fact that some components that have been proven to cut fuel consumption aren’t included in EPA’s model for the fuel economy standard. According to Charlie Allen, general manager-rear drive axles, North America, for Meritor, proving the value of certain component specifications, such as drivetrain components or automatic tire inflation devices, will require some work. “This thing is kind of convoluted; it’s not clean,” he says. The government has only put a small number of components or technologies in the computer model, and it needs to acknowledge that there are other components that can in fact create a meaningful difference in fuel economy, Allen says. “The basic technologies that go into the regulations are a really short list.”
Component manufacturers will have to prove a specific technology improves fuel economy with the truck OEM, which in turn will then have to make a case for the component to the government. For example, Allen says, changes that are made to the engine to run at the most efficient rpm may require different axle ratios, “so we might see changes in what axle ratios are available in certain vehicles.”
Another example of a component that is a proven fuel saver but not considered in the regulations is transmissions, according to Steve Spurlin, executive director, application engineering and vehicle integration, for Allison Transmission.
Shifting to keep the engine operating in the “sweet spot” for optimum fuel economy has become increasingly difficult as engines are redesigned to meet EPA emissions requirements, making automatic and automated manual transmissions more attractive to truck fleet owners. And as time goes on, Spurlin says, taking driver ability out of the fuel economy equation will become more of a factor as new drivers enter the industry with no experience driving a manual transmission vehicle.
“With every shift of a manual transmission, engine torque stops and it wastes fuel,” Spurlin explains. “Automatic transmissions make it easier for the driver to keep the engine running in the most favorable spot for fuel economy.”
While fully automatic transmissions have mostly been a spec for vocational customers, Allison is currently testing the TC10 tractor series that the company says is targeted for applications where a tractor-trailer splits its work cycle between urban and highway conditions. Its design is the “best of both worlds because it incorporates Allison’s proven torque converter and full power shifts with a 10- spd. twin countershaft gearbox,” Spurlin says. “Real-world fleet testing to date has shown the new TC10 gets better fuel economy than comparable automated manual transmissions in the targeted duty cycles.”
Limiting options could cut costs
Limiting spec options may not be all that bad, says fleet consultant Bruce Stockton, former vice president of maintenance for CFI and Con-way Truckload. “As a truck buyer, you will have fewer options in trucks going forward,” Stockton says, “but that will result in less complexity for truck manufacturers and may help keep truck prices down.”
Fleets in North America have been spoiled, Stockton says. “Because of competitiveness in the marketplace, truck OEMs have offered every option fleets want. The good part about this fuel mileage regulation is that it will force truck OEMs and truck fleets in the U.S. to reduce complexity in their specs,” Stockton says. “It won’t lower the price of a truck today, but it will curtail the high escalation in prices. We will end up with a truck that is a much more common spec, which will help cut the price of truck production.
“If you ask fleets why they spec a certain component, they will usually say, ‘Because we always have,’” Stockton continues. “A lot of the time they will have specialty specs and don’t really know why.”
Stockton says that while fleets may balk at limited truck and component options, it will benefit them in more ways than one. “When I consult with fleets, my general overriding recommendation is to find the type of truck and specs you need to do the job and stick with one brand. With multiple brands, you have parts complexity and training issues for drivers and for the mechanics who have to work on all the different trucks.
“There are so many options these days and as trucks become more technologically advanced, new trucks have even more downtime,” Stockton continues. “If the industry doesn’t accept a more generic truck, our costs are going to just continue to go up and up.”
Dave McKenna, director-powertrain sales and marketing for Mack, concurs that the number of options available, especially for linehaul tractors, are extreme, citing that there are 800,000 iterations of Mack’s highway models. And those are vehicles that will be most impacted by the fuel economy regulations.
“Things that are options today will probably be the law tomorrow,” McKenna says. “You can order whatever tire you want today, but in the future it may be difficult to order a tire that’s not low-rolling resistant. Today, engine shutdown is optional. In the future there may be actual limits set. Road speed limiters will become a standard.” McKenna says that while the need for speed limiters on all trucks is a foregone conclusion, he hopes that U.S. regulators don’t go the way of Canada.
“In Canada, they set speed limiters on all heavy-duty trucks at the same speed, with unintended consequences,” McKenna says. With all the trucks geared to run at the same speed, they can’t get out of each other’s way. It creates huge traffic jams because the trucks can’t pass each other.” McKenna says regulation is what drives innovation, pointing to Mack’s solution to the speed limiter problem. “Puff-top” speed limiters would set maximum truck speed at, say, 65 mph, but would allow the truck to speed up to 68 mph, for instance, for a certain amount of time. “This would give drivers some flexibility. I’ve seen what happened in Canada where the speed is fixed—and it’s ugly.” “It’s what keeps me excited in the industry,” McKenna adds. “They come up with all these regulations, and we can come up with an innovation that doesn’t negatively impact the customer and how they do business.”
With the price of diesel spiking to more than $5/gal. in some areas and his fleet pumping some 14 million gals. of fuel a month, one fleet executive says he isn’t waiting for a government mandate to tackle the fuel economy issue.
Max Fuller, chairman of U.S. Xpress, is already utilizing most of the fuel-saving measures that will be mandated for all carriers in 2014 and 2018 in his Chattanooga, TN-based fleet. And he’s instituted his own testing of fuel-saving technologies with the help of the University of Tennessee at Chattanooga’s SimCenter for Computational Engineering.
“This is the same kind of technology that has been used in the space program and in the military,” Fuller says. “We are applying similar principles to our industry and are discovering some amazing facts.”
For example, SimCenter research that focused on a gap-closure design between the cab of the truck and trailer showed the potential for a significant increase in fuel efficiency, Fuller says. According to estimates by the EPA’s SmartWay program, U.S. Xpress saved 63,179,217 gals. of fuel and prevented 701,289 tons of carbon dioxide in 2008 alone.
“We believe that conservation is good business,” Fuller says. “We have been very fortunate to have worked with the National Center for Computational Engineering at the University of Tennessee at Chattanooga. The computer simulation models generated by these researchers allow us to test possible prototypes before they are manufactured. The computer simulations save on research and development costs, which lead to the production of a more effective prototype, especially in the area of aerodynamic improvements.”
Real-world testing
Most truck fuel economy testing is done in wind tunnels with the wind coming straight at the truck. But in the real world, wind comes at a vehicle from different angles. “With SimCenter, we’re able to test trucks and components from all angles,” Fuller points out. “We found that some trailer fairings worked great straight on, but not when you look at yaw factors. The same holds true with tractors. With SimCenter testing, we can see many more variables.”
U.S. Xpress has also seen a “definite benefit” in fuel savings by using automatic engine shutdown and speed limiters universally in the fleet. But getting drivers on board with these two measures can be the trickiest part of the fuel economy equation, Fuller says. “Anytime you cut the drivers’ ability to make money, there is going to be heartburn with it. You can’t blame ’em. You have to give them something in return. We offered the drivers more in pay, but we make up for it in fuel savings.”
Communication with drivers is key. When automatic engine shutdown was first introduced, drivers complained, Fuller says. However, they quickly got on board when the fleet created videos explaining regulations and how much the company spent in fuel costs.
“The driver community is really sharp,” Fuller says. “They understand what 200 gals. of fuel costs, so they’ve been generally accepting. If you don’t communicate, when you make a policy change, you’re going to get backlash. When you give drivers the facts, especially when fuel prices are high, they are usually ready to work with you, especially if you address their issues as well.”
Fuller says the fleet also had engine supplier engineers ride along to see how drivers were performing and put monitors on the trucks to see how the engine was performing for fuel economy. The fleet was able to improve fuel economy 4.5% just by tweaking the engine parameters and adding automatic engine shutdown.
In conjunction with the automatic engine shutdown, U.S. Xpress also worked with Espar Heater Systems to redesign cab heaters to include a thermostat so drivers could regulate the heat to the cab. “They were so efficient that they got the cab too hot,” Fuller says of the earlier design that only had settings of low and high. “And low wasn’t even low enough.”
“To create awareness and empathy with the driver community, we had the president of our truckload division spend the night in a cab to test the heaters to show that we will walk in their shoes before adding anything,” Fuller adds.
Managing hotel loads
The fleet also added battery and alternator capacity to help manage hotel loads such as CPAP machines for sleep apnea, microwaves, mini refrigerators, charging computers, cell phones, and TVs.
Fuller says he hasn’t found a cost-effective solution for air conditioning yet. “We’re looking at electric cooling systems, but we need to find one that’s good for 8 to 10 hours and is still affordable. Haven’t found one yet.” In the meantime, idle parameters on the trucks are set so that if ambient temperatures are above a certain level, drivers will be able to idle the engine to stay cool.
APUs are too costly to maintain and add too much weight to the vehicle to be considered, Fuller points out.
Conforming to emissions regulations has already added almost 2,000 lbs. to the weight of the truck, he says. “Adding an APU can significantly increase the weight of the vehicle,” he explains, pointing out that the lightest APU on the market weighs 450 lbs., with others weighing as much as a couple thousand pounds. “You’re taking away payload with each addition in weight.”
U.S. Xpress also specs automated manual transmissions, which will soon be on 100% of the company’s trucks. “With good drivers, we don’t see much improvement in fuel economy with automated transmissions, but with bad drivers, there’s significant improvement,” Fuller says. With automated transmissions, trucks run in a much tighter range and in an optimal fuel curve. They also prevent aggressive drivers from shifting into higher gears too fast.
When figuring fuel economy, many fleets fail to monitor truck routes to avoid congestion. The goal is obviously to minimize the number of miles the fleet operates, he says, but it’s also important to put drivers in the most efficient lanes. “If the shortest route pu\ts him through the middle of town and the driver gets stuck in traffic, that doesn’t make sense, ” Fuller points out.
Taking mirrors off the hood of the tractor and adding cameras saves the fleet 0.5 mpg. The fleet also specs horizontal exhaust to eliminate drag and a 3-in. fairing onto the back edge of the cab fairing on the roof to achieve another 0.25 mpg in fuel savings. Shortening the gap between cab and trailer by moving the fifth wheel improves mpg between 0.2 to 0.3. Fairings under trailers improve fuel economy another 4% to 7%, depending on the fairing used. Even the type of mudflap used impacts fuel economy, Fuller says. Instead of solid mudflaps, the fleet now specs serrated flaps that eliminate drag.
If there’s anything about the new regulations that’s for sure, Fuller adds, it’s that it will cost the trucking industry— and probably those costs will be much more than the government estimates. “Anytime the government tells us what to do, it’s going to cost us more. And when you look at what they say it’s going to cost, you should then multiply that by at least 10.”
Changing drivetrain and tire specs
Another carrier executive that says he’s not going to leave fuel economy measures to truck OEMs is Randy Cornell, vice president of maintenance for Con-way Truckload. “A combination of things have to happen to meet the new regulations,” he says. “I’m not going to leave it up to the manufacturers. We’ve had some pushback from some of the manufacturers, but it’s working.”
The biggest change in specs the fleet has made to improve fuel mileage is the switch from a 6x4 tractor to a 6x2 configuration. “We stepped out on a limb with a 6x2 tractor rather than a 6x4, and we’re probably the biggest carrier to do that.”
The beauty of the new tractor configuration is that “the driver doesn’t have to do anything different to get better fuel economy. We try to choose passive systems where fuel economy will happen without the driver having to do anything. We found we got the most bang for our buck with the 6x2 tractor,” Cornell says, and the fleet realized 0.4 mpg improvement in fuel economy by spec’ing that configuration. “That’s a huge amount of dollars when you do the math, especially for a fleet our size.”
Con-way Truckload was probably the first fleet in the country to run predominately wide base tires. It started spec’ing single wide tires 10 or 12 years ago, when the fleet was known as CFI, starting with company tractors and than moving to wide base tires on trailers. Currently, the fleet runs wide base tires on 100% of its tractors and about 97% of its trailers. Switching over, Cornell says, is a lengthy process. “Obviously, you can’t just change the tires out on 2,600 trucks and 8,000 trailers; you have to do it over time.” The use of wide base tires has provided the carrier with a fuel economy improvement of about two-tenths of a mile. And Cornell says tire suppliers have “really improved the network out there where you can get replacements; it’s significantly better than it was 10 years ago.”
Driver Education
Teaching drivers how to drive to maximize fuel efficiency is a critical piece of the fuel economy equation, he says. Con-way monitors drivers for fuel economy performance; if they have issues, the company brings them in for hands-on training on driving techniques. Spec’ing automated transmissions also took some of the driver factor out of the equation, Cornell says.
Improving fuel economy is made up of a lot of little pieces, he says—aerodynamics, tires, engines, gearing of engines, speed and idle limiters, just to name a few. “There’s not any one smoking gun,” he adds.
