Most fleets would confess to using fuel additives from time to time, most likely in the winter to prevent gelling. But there are fleets, lots of them it seems, that regularly treat their fuel with additives of some description. Some use detergent additives or lubricity agents to make up for the loss of sulfur in diesel fuel, which disappeared under a government mandate back in 2006. Others use fuel stabilizers to offset the effects of aging, and cetane improvers to optimize combustion — or in the words of some additive suppliers, “to increase horsepower and reduce emissions.”
It’s easy to be skeptical of such claims, but evidence suggests there’s some truth there.
“Many different problems can be solved or avoided all together when including fuel additives in a fleet’s maintenance plan,” says Kevin Adams, director of research and development for Lubrication Specialties Inc., makers of Hot Shot’s Secret. “One of the most common problems, and perhaps the most easily avoided, relates to the condition of the injectors. By using the correct fuel additives, injector damage due to water and internal diesel injector deposits will be prevented. When a lubricity additive is used, the life of the injector is increased.”
In most cases you’ll never know if the product is working or not. How does one gauge the condition of an injector short of tearing it down and examining it? If it fails, you might do that, but if it doesn’t fail over its expected life, is that a result of the additives you used? Or would it have been fine without it?
In other instances, it’s easier to tell if the product is working. If you suffer from fuel filter plugging, for example, an additive can help dissolve the asphaltenes. These are high-molecular-weight hydrocarbons that are usually found on the bottom of the crude. They can also be formed in ultra-low-sulfur diesel fuel from the heat created by higher pump pressures inside the fuel system and returned to the tank from your fuel pressure regulator, notes Adams.
“High-performance fuel additives can contain ingredients that not only dissolve the asphaltenes that are already present in your fuel, but also help prevent asphaltenes from forming and plugging filters,” he says. “Additionally, many trucks suffer from the effects of a low cetane rating within the fuel that causes poor fuel economy and hard starts during the cold months,” Adams adds. “A good fuel additive will boost the cetane number and solve each of these fuel-related issues.”