Managing fuel expenses.

The nation's trucking companies live or die on how well they control their operating costs, and today's historically high fuel prices are making it difficult for many of them to manage their costs effectively. Since a strong correlation exists between diesel fuel prices and trucking company

The cost of fuel represents the second-highest operating cost of any North American truck operator, exceeded only by costs associated with wages and benefits. When prices are stable, fuel remains a controllable and manageable expense. But when prices climb rapidly, trucking firms must focus on reducing fuel consumption.

Since last fall, diesel fuel prices have increased substantially and--at an average retail price of $1.48 per gallon in mid October--prices were more than 10 percent above year-earlier levels. In this challenging economic climate, trucking companies face a difficult challenge of raising freight rates to compensate for the rise in energy prices. That explains why fuel economy, always an important operating-cost issue, has become absolutely critical.

According to Jordan Feiger, vice president and general manager of the Heavy Vehicle Center at International Truck and Engine Corporation, an analysis made by his company regarding the historical impact of diesel fuel prices on trucking company bankruptcies reveals that per-gallon prices in the range of $1.40 represent a danger zone for fleet owners, all area in which they must remain vigilant with fuel costs. Further analysis reveals a certain lag effect in which trucking company bankruptcies occur five or six months after a peak in fuel prices. The combination of these phenomena means that bankruptcies actually decrease as diesel fuel prices increase above $1.40 per gallon, but then increase as fuel prices decline and pass below $1.40 per gallon. See Figure 1.

[FIGURE 1 OMITTED]

Right now, prices are hovering markedly above that $1.40/gallon range, which means even the smallest adjustments or steps taken to save fuel can mean the difference between profit and loss, or even between survival and bankruptcy.

Assuming that further improvements to fuel consumption don't occur, the current level of diesel prices has raised the average fuel cost per mile by two cents to nearly 24 cents. And, as Feiger points out, in an industry where operating ratios easily rest in the mid-to-upper 90s, two cents a mile can spell the difference between profits and red ink. See Figure 2.

[FIGURE 2 OMITTED]

There is another factor hurting trackers' ability to improve fuel economy. When the industry's tough 2004 emissions changes were moved up by 15 months, fuel consumption took center stage. While the new standards for engines ensure progress in reducing emissions, fuel economy can be compromised. Potentially, the emission changes can impact fleet fuel consumption if adaptive measures aren't taken. A three-percent drop in fuel economy equates roughly to a one-cent-per-mile increase in operating costs. See Figure 3.

[FIGURE 3 OMITTED]

So what can fleet manager do? Feiger has some suggestions. He says, "Fortunately, firms can enhance their fuel management by, among other things, improving driving habits, limiting top road speeds, controlling engine speed and focusing on truck aerodynamics. Indeed, these four key categories capture the leading elements that contribute to fuel consumption."

He offers an overview of those categories and what steps will help improve fuel efficiency.

Vehicle aerodynamics

For a typical Class 8 on-highway tractor traveling at 55 miles per hour, aerodynamic drag contributes 42 percent to fuel consumption. This figure climbs to 50 percent at 65 miles per hour.

Within the two basic models of Class 8 tractor designs, aero (set-back front axle and sloped hood) and classic (set-forward front axle and square hood), the styling of the cab and hood can improve fuel efficiency by minimizing airflow resistance and the drag forces that result from this resistance.

A properly designed truck cab and chassis moves through the air with minimal disturbance, achieving air that is "laminated," or attached, to all sides of the truck resulting in reduced drag. Bent bumpers and cracked hoods disrupt airflow, increasing the drag coefficient and fuel consumption. Feiger even recommends taking a tip from NASCAR and bending bumpers back into place and using duct tape on hood cracks until proper repairs can be performed. Further, components such as bumpers, mirrors, grab handles and sun visors can inhibit smooth airflow and increase fuel consumption unless they are specifically designed, as part of the overall cab shape, to minimize air turbulence. He says the classic or "West Coast" tractor is further disadvantaged because of the external air cleaners and cab-mounted exhausts that timber disrupt airflow around the cab because of the abrupt design changes.

Feiger points out that International Class 8 vehicles feature patented air-fairing shapes and claims that these combine with other optional aerodynamic devices, such as cab extenders and chassis skirts, to contribute to industry leading performance in this area.

Drivetrain

For a typical Class 8 over the road tractor, drivetrain mechanical inefficiencies can contribute up to 21 percent of fuel consumption. For example, the selection of drivetrain gear ratios plays a key role in a truck's operating and efficiency characteristics, In most cases, a "gear fast--run slow" configuration will produce the best overall balance between performance and efficiency.

The engine system, which includes accessories, turbocharger, cooling module and exhaust system, also can impact drivetrain efficiency. Feiger suggests that a truck-and-engine system is best engineered as an integrated package to ensure low operating costs, maximum performance, durability, reliability and driver satisfaction.

Reflecting recent emission-related power-system changes, most truck manufacturers have narrowed their engine offerings to ensure that this tailoring of truck and engine offerings maximizes and operator's performance and economy.

Feiger says that with the newer engines that have narrower "efficiency" ranges, the opportunity for fuel economy exists linked with the use of 13- and 18-speed manual transmissions in the hands of a veteran driver. The additional gears allow the driver to keep the engine in the "sweet spot" for best fuel economy.

Similarly, the emergence of automated transmissions should help fuel efficiency. While automation doesn't automatically deliver fuel efficiency, it allows less-experienced drivers to shift as well as a veteran driver by making some of the shift decisions, and this can improve fuel economy. Feiger says that International customers report that they've seen fuel-economy improvements of 0.3 to 0.6 miles per gallon on vehicles equipped with automated transmissions.

Finally, the use of synthetic lubricants in most axle and transmissions can improve fuel economy by as much as two percent during the colder winter months, according to Feiger.

Roiling resistance tire type, tread design, alignment and air pressure should be carefully managed to promote fuel economy. The effect of tire roiling resistance, which can reach 37 percent, trails only aerodynamics among product features that can adversely impact fuel economy. Tires intended for highway use have much better fuel efficiency than on/off road tires. And rib tires have a higher level of fuel efficiency than deep-tread, aggressive-lug tires.

Although fuel efficiency is better with rib tires all around, most line-haul customers demand traction tires on drive axles. This has led most tire makers to develop fuel-efficient drive tire designs that maximize fuel economy while maintaining excellent traction and providing high mileage. Other factors such as tire-inflation pressure, can impact fuel economy by as much as two percent.

Feiger reminds fleets that axle and wheel alignment play an important role in overall fuel economy. Indeed, it is possible to affect fuel economy by as much as 2.2 percent with improper front wheel and axle alignment, because overcoming the extra rolling resistance from misalignment requires extra fuel. In essence, you're burning more fuel to wear your tires out faster. Truck operators often overlook this area when seeking to improve fuel efficiency.

Another factor that influences roiling resistance is vehicle weight. It may come as a surprise, however, that tractor weight variation plays an almost insignificant role in the vehicle's overall fuel economy performance. In fact, a 600-pound increase costs only 0.02 miles per gallon, a fraction of the total rolling-resistance impact.

Driver performance

Drivers play the deciding role when it comes to a large number of factors that address fuel economy, including shifting techniques, gear selection, road speed, engine speed, route selection and the amount of idle time. Feiger reports that fleet analyses done by International show that fuel economy can be impacted by as much as 35 percent due to driver technique. Road speed alone can impact fuel consumption significantly. Reducing road speed to 60 mph from 65 can save about eight percent in fuel.

This is very close to the rule of thumb established by ATA's Technology and Maintenance Council (TMC) in 2000. It says that one mph equals 0.1 miles per gallon. In other words, a five mph reduction in average road speed would result in a 0.5-mpg fuel economy improvement.

Excessive engine idling represents another critical issue, one that state and federal agencies are examining from an emissions perspective. Truck operators, though, should view it from an operating efficiency standpoint. Excessive idling not only increases fuel consumption but also reduces the life of the engine. Fuel-consumption tests by the TMC and the Society of Automotive Engineers (SAE) reveal that heavy-duty diesels consume one gallon of fuel for every two hours of idling, and it is common to see 30 percent-to-50 percent of a fleet's total engine operating hours spent idling.

TMC guidelines suggest that reducing idling to zero from 50 percent could save fleets 10 percent in fuel consumption. A truck running 125,000 miles per year and averaging six miles per gallon, will consume 20,833 gallons of fuel. At $1.42 a gallon, a 10 percent savings would equate to $2,958 per truck each year.

Operations

Route selection represents another important factor because it can impact fuel economy by five percent to 10 percent. Simply selecting better highways for main routes can improve a fleet's fuel economy, and some of today's routing software may help select the routes that can maximize fuel consumption.

Efforts to further enhance trucks' fuel economy continue with a number of research and development activities underway. The 21st century truck initiative launched in 2000, for example, is a multi-year collaborative partnership between heavy-vehicle manufacturers, key industry suppliers and the government to improve truck fuel efficiency, emissions and safety significantly.

Feiger describes several fuel-economy initiatives moving forward at International including the use of "intelligent tire" technology to monitor tire pressure and temperature. Under-inflation by 10 psi can reduce fuel economy by five to six percent. The use of wide-base, single drive tires also is being examined. These can improve fuel economy by at least two percent. And development of "fuel economy" focused shift patterns with automated and automatic transmissions can further enhance the benefits of these transmissions to reduce the variability between drivers.

Feiger says, "In today's challenging economic environment, especially as diesel fuel prices stay at historically high levels, every effort to economize on fuel can save big bucks--and, perhaps, the truck operators themselves."

Figure 2

Fuel Economy on the Road

                                       Change       Effect (mpg)
Items influenced by specification
    aerodynamics                   +/- 10% cd (1)      +/- 5%
    tractor weight                 +/- 10% lbs (2)    +/- .05%
Items influenced by operation
    tire inflation                   +/- 10% psi       +/- 1%
    speed                          +/- 10% mph (1)     +/- 8%

(1) @ 65 mph
(2) on 16,000 lb sleeper

Fuel Economy on The Road

Ray Williams, vice president of maintenance at Estes Express Lines shares some of his fleet's efforts to control fuel costs.

To address the high cost of fuel, our fuel supervisor ensures that we are getting the lowest possible fuel price. The fuel supervisor also monitors what areas we can obtain low-priced fuel in the event a driver is unable to refuel at their terminal.

We purchased the aerodynamically designed International 8600 single and tandem axle tractors and added aerodynamic air fairing packages to the units, which increase fuel economy. We recently changed the rear axle ratio to a lower numerical ratio in order to lower the rpm of the engine for the purpose of increasing fuel economy. About five years ago, we changed to synthetic fluids in the axles and transmissions.

We have also instituted a preventive maintenance program, which includes frequent tire pressure checks during regular preventive maintenance inspections. These checks are also conducted at the inbound lane when the truck returns to the terminal. We use a single-source tire retreader which mounts and dismounts our tires and maintains the tires at the proper inflation level.

Our local dealer, International Truck Sales of Richmond, sets up training through International for our shops' technicians on how to diagnose, troubleshoot and maintain our equipment.

We have a driver training program for new and current drivers that teaches basic driving techniques and how to do a pre-trip inspection of the tractor each day. The tractors are also equipped with the idle shutdown feature, which will turn the tractor off at a preset interval.

Our operations department utilizes software that prompts the driver to take the most efficient route possible when delivering freight.

We have found that the fuel economy of the new EPA Cummins engines is comparable to the former emission engines.