If there was a way to learn how to maximize diesel fuel economy, the majority of diesel fleet owners would jump at the chance. This blog post will propose two very simple strategies that could increase fuel economy by as much as 8%. That may seem like a fairy tale, but there are diesel operators that have followed these two approaches to gain this type of improvement.

What Causes a Diesel Engine to Lose Its Fuel Efficiency?

Once of the main issues causing diesel engines to run inefficiently and deliver poor fuel efficiency would be deposits forming on fuel injectors. Diesel fuel is forever changing in quality and this causes injector problems. In the past, deposits tended to form on the tips of injectors. Now, these same deposits are starting to form internally. Today, there are low sulfur, ultra low sulfur, and bio-based diesel fuels.

Blue Peterbilt truck.

Deposits inside injectors are caused by the varying and lower sulfur diesel fuels. The result, unfortunately, is poor fuel efficiency and reduced engine power because of injector spray patterns being adversely affected.

To refine these low sulfur diesel fuels, much of their natural lubricity has been taken out. The refining process to create such diesel fuels has resulted in fuels that are weaker in a few areas. They are weaker in thermal stability, and they are weaker in the level of antioxidants. Coupled together with weaker fuels and combining that with the highly engineered injection systems, these fuels are forced to operate at much higher temperatures.

Diesel banner ad 2.

What is causing the problems is not the injection systems, but the varying degrees of quality of diesel fuels available to diesel operators. Because these fuels are susceptible to being thermally unstable and prone to oxidation, both these problems leads to deposits forming within the injectors. When this happens, the precise spray patterns that are required for maximum engine efficiency and fuel economy become compromised.

Instead of a perfectly even spray pattern, the deposits start to cause uneven spraying. Over time, if left unchecked, engines lose power, efficiency, and waste precious costly fuel.

How to Maximize Diesel Fuel Economy

Use a High Performance Fuel Treatment

Volvo truck.

If fuel economy robbing deposits can be removed from injectors, then there is the potential of up to 8% better fuel efficiency.

A simple yet effective strategy would be to use a high-performance diesel fuel treatment. There are some experienced and clever lubricant manufacturers that are designing diesel fuel additives that actually deliver on the benefits they claim to provide. Look for a diesel fuel treatment that utilizes a heavy oil base rather than an alcohol-based formulation. Such a product will provide critically needed lubrication to the upper cylinder and ring area of an engine and also protect critical components of the fuel pump and injectors.

Conduct your own research to be sure that the specialized diesel fuel treatment provides superior fuel injector cleaning. The goal is for the fuel conditioner to safely soften and dissolve accumulated deposits found either on the tips of the injector or internally. This is accomplished through advanced chemistry that effectively should clean up a dirty fuel system.

Diesel banner ad 1.

The goal is to get the injectors as clean as they were when new. A quality fuel additive should be able to accomplish this over time. Once this is reached, then the diesel engine should be able to reach maximum combustion efficiency. In-the-field testing usage of such a diesel fuel additive has delivered diesel operators fuel economy improvements as high as 8% after cleaning the injectors with such a diesel fuel treatment.

This is one simple solution in how to make a diesel engine more fuel efficient. Of course, beyond fuel economy, any lost engine power will be returned along with increases in power. Also, another added benefit to these specialized diesel fuel additives would be reduced exhaust emissions, which is an important benefit due to stricter government environmental regulations imposed on diesel operators.

Blue cement truck.

Switching to a high quality diesel fuel additive such as AMSOIL Diesel All-in-One will restore horsepower and improve fuel economy.

Digging a little deeper into the benefits in using a custom blended diesel fuel treatment that improves diesel fuel economy would be how it deals with maintaining fuel stability and providing corrosion protection. A well engineered diesel fuel conditioner should provide and maintain diesel fuel stability and protection against fuel oxidation. Solving these two issues will prevent sludge and filter plugging, as well as prevent deposits.

Corrosion is always a potential issue for diesel fuel system components. If critical parts start to corrode, the life of the engine is reduced, maintenance costs rise, and engine performance starts to diminish. It is important to be sure that the diesel fuel treatment chemistry contains robust volumes of corrosion inhibitors. These corrosion inhibiting agents will protect fuel systems from rust and corrosion.

Utilizing a Synthetic-Based Engine Oil

The second strategy we propose in how to make a diesel engine more fuel efficient would be determining whether moving to a synthetic-based motor oil could bring fuel economy improvements. There are major differences between conventional diesel motor oils and synthetic-based diesel engine oils. Structurally, conventional motor oils utilize base stocks whose molecular structure is uneven and of different sizes. What this means is that the motor oil does not flow easy. This translates to excessive fluid friction.

These unevenly sized molecules require the engine to expend more energy because of the fluid friction it is causing. Beyond the basic molecular structure of conventional diesel oils is the fact that they have unwanted byproducts that over time leave damaging deposits. The buildup of deposits such as gum, varnish, and sludge can cause an engine’s performance and efficiency to drop. All this contributes not only to inferior fuel efficiency, but a lack of power and a reduction in engine life.

Large semi truck on wooded highway.

Can changing to a synthetic motor oil help maximize diesel fuel economy? Experience has shown that this is definitely possible.

Diesel engine oils that are based on synthetics utilize oils that are essentially made in a laboratory. Their molecular structure is even and of the same size. This is significant when the goal is to improve fuel efficiency. When the molecular structure is even, the oil flows evenly and with far less fluid friction. By utilizing an engine oil that flows easy, this means the engine will expend far less energy. When an engine uses less power, this translates into a savings in fuel because less of it is burned.

Diesel ad 3.

By utilizing 100% pure synthetic base stock oils, you get an engine oil that has eliminated all the negative aspects of a conventional engine oil. It is man made and designed to specifically reduce friction, withstand heat, pour easily during cold temperatures, and provide maximum protection over a wide range of temperatures. Synthetics are superior base oils that protect the engine far better and with minimal, if any, deposits. Also, they withstand much higher temperatures because of their superior thermal stability and resistance to oxidation. Remember, if an oil can withstand excessive heat and is resistant to oxidation, your diesel engine will stay clean and protected.

At this point, we can see that some of the added benefits offered by 100% synthetic diesel engine oil  are that your engine works easier, more efficiently, and burns less fuel. Next, it is important to look at the additive chemistry that is blended into these specialized base oils. With the same goal of improving fuel economy, it is critical that the engine oil incorporate friction modifying additives to help further reduce friction.

There’s one other benefit that needs to be mentioned in regards to using a 100% synthetic based engine oil that includes friction modifiers and anti-wear agents. More than 80% of engine wear occurs at initial startup. Since synthetic base oils flow easier than conventional oils, then during startup, an engine will turn over easier and experience less wear with synthetics. Utilizing an oil that has friction modifiers and anti-wear agents further helps cold weather start ups.

Large semi truck near lake.

Not only can a 100% synthetic motor oil increase fuel economy, but it will also extend engine life and improve the overall fuel efficiency of the diesel engine.

The last factor to consider in how to make a diesel engine more fuel efficient would be choosing its viscosity. To get maximum fuel efficiency, choose a 5W40 high-performance diesel oil over a 15W40. By going down to a 5W40, cold weather performance is vastly improved. The oil throughout all temperatures will flow with less friction, but still give maximum protection during extreme temperatures and engine loads. This blog post has presented and easy and simply strategy in how to maximize diesel fuel economy.

By coupling a high performance diesel fuel additive such as AMSOIL Diesel All-in-One together with AMSOIL Signature Series Max Duty Synthetic Diesel Oil 5W40, you have a two-part system that works synergistically together to provide your diesel engine with fuel economy potential up to 8%. The numerous benefits your engine reaps, such as less wear, efficient fuel consumption, peak efficiency, and maximum fuel economy all add up to more money in your pocket.

Truck at sunset.

Choosing the best diesel fuel additive together with 100% synthetic 5W40 engine oil will help you get the desired fuel economy for your diesel engine.