The Impact of Fuel Additives on Fleets: Keeping a Realistic Approach

When you’re managing a fleet of commercial vehicles, every mile counts. Dependable fleet operation depends on efficient engine operation, and fuel plays a critical role.

This is often why fleet managers may consider using fuel additives to improve engine performance. Additives are chemical compounds designed to improve engine efficiency, delivered either premixed with a fuel supply or as an aftermarket source.

However, there is little research directly linking fuel additive usage to improved engine performance—and any meaningful difference might take a long time to detect. Engine condition and vehicle age can also limit additive impact, so older vehicles might not see a definitive mileage or performance improvement.

Still, fleet managers might consider using additives as a long-term solution for extending engine lifespan. Replacing a complete engine is more expensive than buying occasional aftermarket additives (or using premixed fuel). If you’re considering using fuel additives for your fleet, first recognize the different types of additives commonly used.

Types of Fuel Additives

Fuel providers and aftermarket suppliers often combine additive formulas for “all-in-one” solutions. Premixed fuel, like TOP TIER™ gasoline, contains multiple detergent additives that help reduce engine “gunk” and limit buildup on intake valves. Aftermarket additives might target specific engine functions for improvement, like combustion efficiency.

Some common types of fuel additives include:

• Cetane boosters. These additives increase the cetane levels in diesel engines, reducing ignition delay. Higher cetane levels allow the fuel to burn quicker and ignite faster, which is especially important in cold-weather situations. Long ignition delays in cold climates risk engine damage and vehicle stalling.
• Octane boosters. These additives provide a temporary increase to the fuel’s octane levels. Standard gasoline operates with an octane level in the high 80s, with more premium options in the low to mid 90s. Higher-octane fuels can withstand more detonations in an engine’s combustion chamber than lower-octane fuels.
• Fuel system cleaners. These additives focus on breaking down gunk and other materials that build up inside engine injectors. Look for cleaners that contain polyetheramine (PEA) or polyisobutene (PIB), which are known for their cleaning properties. Cleaners won’t fix a faulty fuel injector, though.
• Lubricity agents. These additives reduce friction between an engine’s moving parts. Historically, diesel engines used sulfur to lubricate engines and reduce friction. However, environmental regulations mandated a shift to oxygen-based biodiesel options. Modern agents form a durable, protective film on the surface of fuel components, limiting friction and prolonging engine life.
• Demulsifiers: These additives help separate water from fuel, which can help prevent water damage to an engine. Contaminated or low-quality fuel can lead to engine problems, reduced fuel economy, increased emissions, and costly repairs. Demulsifiers can also help limit ice buildup in the fuel lines from cold climates.

Be Realistic about Additive Impact

The fuel additive market is saturated with claims about immediate results and improvements—and a lot of skepticism about those claims. If you’re considering using additives for your fleet’s engines, make sure you understand the purpose of the additives—and be realistic about their benefits.

• When used properly, additives can help improve a vehicle’s fuel economy, reduce carbon emissions, protect vital engine components, or extend the engine’s life.
• Don’t expect immediate results from most additives, however. Fuel system cleaners might have a faster impact by reducing grime and buildup, but additives that address fuel economy might result in changes seen only over multiple tanks.
• Only use additives that address an engine’s (and a vehicle’s) intended use. Cold-weather additives are specifically made to reduce fuel gelling and spark faster ignitions. They won’t help much for vehicles driven primarily in hot climates.

Test Additive Effectiveness

If you’re introducing a new additive to your fleet’s vehicles, you’ll want to determine its effectiveness. It takes a steady, systematic approach to test additive impact, both in controlled settings and in real-world usage.

Controlled testing:

• Establish a baseline. Inspect and evaluate a group of vehicles before introducing any additives. This will serve as a baseline for comparison.
• Introduce the additive. Add a specific additive to one group of vehicles while maintaining baseline conditions for another group.
• Measure performance. Monitor fuel economy, engine emissions, and overall vehicle performance using diagnostic tools and data logging systems.
• Analyze data. Compare the performance data of the treated and untreated vehicles using statistical analysis to determine the additive’s effectiveness.

Real-world testing:

• Ask drivers for feedback. Collect feedback from drivers about their vehicles’ performance before and after additive usage.
• Look at maintenance records. Identify any changes in engine wear or repair frequency.
• Evaluate over a long term. Monitor the performance of vehicles over an extended period to assess the additive’s long-term effects.

Fuel and oil additives, when used properly, can positively impact the lifespan and performance of your vehicles. Keller-Heartt offers Diesel Fuel Supplement and Diesel 911 from Power Service Diesel Additives, which are designed to fight contamination and ensure a long engine life. Contact us today if you have any questions about additive needs or fleet performance.