The high cost of gasoline, conflicting information about new alternative fuels and the increasing availability of hybrids are all issues generating significant interest among contractors wondering how this impacts their companies’ fleets. Although some changes have been mandated—such as the new EPA requirement that all diesel engines be equipped with diesel particulate filters, revised catalytic converters and EGR (Exhaust Gas Recirculation) valves to comply with limits for ultra low diesel soot emission limits—the vast majority of alternatives are completely optional.

With so much information available, it is important to make decisions based on what is right for your company and how it uses vehicles, as well as what is best for the environment.

Fuel Options Fuel Questions  

While the debate continues between diesel fuel and traditional gasoline engines, major advances are taking place in both categories.

For example, a clean diesel fuel alternative is currently being tested that does not rely on petroleum as its source. Synthetic diesel fuel, synthesized from natural gas, has many advantages over traditional diesel fuels. Its main advantage is decreased exhaust emissions, which are important in the global effort for clean air. Synthesized diesel fuel also outperforms traditional diesel fuel in engine performance. And, although this new fuel currently costs approximately 10 percent more, prices are expected to come down.

Because no engine modifications are required with the use of synthetic diesel fuel, it appears to promise a new opportunity to use alternative fuels in diesel engines without compromising fuel efficiency. This advancement in diesel fuel will have a positive effect on the environment and the future of the diesel engine.

In the gasoline category, major advancements include E85 fuel. Compared to today’s gasoline/ethanol blends that have up to 10 percent ethanol, E85 is composed of 85 percent ethyl alcohol (ethanol) and just 15 percent petroleum.

E85 is designed for use in flexible fuel vehicles (FFVs), which can switch seamlessly from using regular gasoline to E85. Typically offered as standard equipment with little or no incremental cost, FFVs are available in a wide range of vehicles, from sedans and sport utility vehicles to pickup trucks and minivans, with new models coming out all the time. Manufacturers include General Motors, DaimlerChrysler, Ford, Isuzu, Mazda, Mercedes, Mercury and Nissan.    

According to the Energy Information Administration, there are currently more than four million light-duty FFVs in the United States and approximately one million new FFVs are being produced each year.

But, although FFVs have been produced since 1991, many owners are unaware that they have an FFV that can be fueled with both E85 and/or gasoline. One reason for the confusion may be that FFVs are designed with only one fueling system. To find out whether your vehicle is included, check your owner’s manual, check the fuel filler door, or see a list of current model year FFVs, available at  

In many ways ethanol is an ideal transportation fuel. In addition to its positive environmental qualities, it is domestically produced and its use supports farmers and rural economies. Currently, 10 percent ethanol is added to approximately one-third of all the gasoline used in the United States. Adding ethanol to gasoline not only fulfills oxygenate requirements for federal clean air programs, it also increases octane and extends the petroleum fuel supply.

For businesses considering how FFVs fit into a fleet management program, a case study published in April 2006, profiling the Northland District of the U.S. Postal Service, which covers Minnesota and part of Wisconsin, reported that a successful alternative fuel program depends on having an accurate fuel tracking system. According to the District’s Manager of Vehicle Maintenance, managers and staff must be educated on E85 goals and procedures to ensure the designated program will be cost effective.  

In addition to ethanol, alternative fuels include natural gas, propane, hydrogen, pure biodiesel, electricity, methanol and p-series fuels. Based on information provided by the U.S. Department of Energy’s Alternative Fuels Data Center, using any of these alternative fuels in vehicles can generally reduce harmful pollutants and exhaust emissions, and most of these fuels can be domestically produced and derived from renewable sources. For more information, visit or

Points to Consider

For the time being, while diesel has the advantage over gasoline in terms of fuel economy, resale and long-term maintenance, gasoline has the advantage when it comes to initial cost, short-term maintenance, noise and cold weather driving.

Overall, diesel has the advantage when it comes to the following:  

  • Fuel economy: Since there is more energy in a gallon of diesel fuel than a gallon of gasoline, a diesel engine can make more power with less fuel than a gasoline engine. Results can very, but drivers can typically achieve 12 to 75 percent better fuel economy by switching from gasoline to diesel power. Also, due to a diesel engine’s ability to vary its air/fuel ratio, very little fuel is used to idle (about one-third of a gasoline engine), so vehicles that must idle for long periods of time make excellent candidates for diesel power.
  • Resale: Typically, the more expensive diesel engine has a better resale value. In addition, diesel engines usually come with greater warranty period coverage
  • Long-term maintenance: Diesel engines turn less RPMs than a gasoline engine and are built stronger. Therefore, they are capable of running more miles at higher power levels before needing major work. However, neglecting maintenance on a diesel engine can end up being more costly than its less expensive gasoline counterpart.


On the other hand, gasoline engines also have advantages, including:  

  • Initial cost: Gasoline engines are less expensive. The higher compression and tighter tolerances needed to ignite diesel fuel require that the engine be designed and built with greater weight and strength, which generally makes them more expensive.
  • Short-term maintenance: Oil changes are less expensive. Diesel engines have a greater oil capacity and larger filters. In addition, fuel filters need to be changed more often in diesel engines. While diesel engines do not require tune-ups like their gasoline counterparts, this typically does not make up the difference due to the extended tune-up interval of modern gasoline engines.
  • Noise: Gasoline engines are quiet compared to diesel engines, which make much more noise, especially at idle, even though new technology has made diesel engines considerably quieter.
  • Cold weather: Gasoline engines are easier to start when the temperature drops below freezing. Although plugging a diesel engine into an external heat source can eliminate this problem, it may be logistically difficult in some locations.   

But in terms of power output and driving, it is difficult to quantify and many drivers will have their own preference. Generally, the heavier the truck and the heavier it is loaded, the better diesel power will feel. Although gasoline engine options for a particular vehicle will usually have greater peak power output, the engine has to run at high RPMs to achieve this power, which it is not designed to do for long periods of time. On the other hand, diesel engines do not require high RPMs to make peak power and are designed to run at maximum power for long periods of time.  

For companies considering Flexible Fuel Vehicles, there are several important considerations:  

  • Fueling Options—The FFV system allows the driver to use any combination of gasoline or ethanol—from 100 percent unleaded gasoline to 85 percent ethanol. This means a driver can use unleaded gasoline if ethanol is not available. Because tax credits are available to stations for the costs of retrofitting pumps and tanks, the number of stations offering E85 continues to increase.
  • Driver Education—While FFVs may use either regular gasoline or E85, gasoline-only vehicles should not use E85. Using E85 in gasoline-only vehicles may cause damage because of the incompatibility of the alcohol fuel with the parts in gasoline-only engines. Performance and emissions also will be compromised.
  • Maintenance and Repairs—Preliminary studies indicate that maintenance costs may actually be reduced for FFVs because of the way E85’s cleaner exhaust emission impacts the engine’s operation/performance.
  • Tax Credits and Incentives—Owners of FFV vehicles may qualify for tax credits or incentives in accordance with requirements for alternative fuel vehicle mandated fleets under the Energy Policy Act of 1992, which specifies that a vehicle must be capable of using fuel blends up to 85 percent ethanol.

Hybrids Require Attention To Details

As contractors add hybrids to their companies’ fleets, they are finding that servicing these high-voltage power vehicles requires special attention. From jacking and lifting vehicles to replacing battery packs and fluids, manufacturers of hybrids encourage owners to strictly adhere to the guidelines provided in the owner’s manual and to have their vehicles serviced only by technicians who are properly trained and certified.  

Hybrids are different. Because a hybrid car uses both a gasoline engine and an electric motor powered by high-voltage batteries, there are unusual features under the hood. As an example, there are few if any belts to check and sometimes, no power steering pump. In addition, hybrid transmission fluid, which needs to be checked, is very different than that used in conventional transmissions.


To further understand the different service requirements of hybrids, carefully read the manufacturer’s repair manual. Compared to most gasoline-powered vehicles, some additional checks and inspections must be performed on hybrids. And, it’s even more important to pay attention to details, such as the proper weight engine oil, hybrid specific coolant, transaxle fluid and correct tire pressure. Even the refrigerant oil used in the air-conditioning systems must be a special non-conducting type due to high voltage systems in most hybrids.

A hybrid vehicle’s cooling system also requires special attention. Because electronic modules for the electric motors run hot, hybrid vehicles have dedicated cooling systems for these components. There’s also a dedicated air-circulating system to cool the batteries. Filters for these systems need to be checked regularly and replaced when needed for the system to operate properly. recommends that hoses, clamps and coolant level of the electronics cooling system be checked periodically and the system serviced according to the manufacturer’s specified intervals.  

But that’s not all. Some hybrid vehicles have two air conditioning systems—one to cool the passenger compartment and another to cool the high voltage components. On these vehicles, the system that cools the battery and electronic components also has a filter than needs to be checked and serviced on a regular basis. These unique features are among the reasons that hybrid owners need to rely on specially-trained technicians to insure proper care of their vehicles.

On the other hand, routine maintenance for hybrids is not that different from regular vehicles. Scheduled maintenance includes the usual oil and filter changes, checks of transmission fluid and engine coolant levels and condition, as well as service at the recommended intervals. In addition, regularly inspecting brakes, rotating tires and checking tire inflation, wipers, filters and fluids are necessary to keep your hybrid vehicle performing at peak efficiency.  

Arrange Service with Qualified Shops

Hybrids present special challenges to service technicians. Technicians must be careful when jacking and lifting hybrid vehicles to prevent damaging the high-voltage cabling underneath the vehicle. Similarly, technicians need to know that during routine service such as oil changes or any type of service, the ignition system should be disabled to prevent the engine from starting unexpectedly, causing expensive damage or injury.  

Hybrids’ powerful and large battery packs, which can sometimes be as much as 200 pounds, also require special attention. Compared to a regular car battery that has 12 volts available, a hybrid’s battery can have over 300 volts available, which can be dangerous if not handled properly. The high voltage wiring is encased in bright orange casing.

Technicians who are trained to work on hybrids are knowledgeable about the unique high-voltage power systems and how these affect the vehicle. They also are familiar with the proper equipment, tools and procedures when working on these specialty vehicles, as well as the safety precautions.

Hybrids continue to attract the interest of businesses because of their environmental and fuel efficiencies. When it comes to servicing your hybrid, it is best to have the work done by specially-trained technicians to keep your vehicle operating at peak efficiency.    


Construction Business Owner, February 2008