10 Best Diesel Additives 2026 in the United States

The Archoil AR6500 Diesel Treatment is a solid choice for anyone looking to improve the performance and protection of their diesel fuel system. It combines multiple benefits in one product, including a strong cetane boost that helps your engine start easier and run smoother by improving fuel combustion. It also cleans and lubricates the fuel system, which is important for maintaining injectors and high-pressure common rail (HPCR) systems, potentially preventing costly repairs.

Additionally, it’s formulated to handle modern diesel fuel challenges, which can include issues like fuel gelling in cold weather and water contamination, thanks to its ability to stabilize fuel and disperse water. The fact that this two-pack treats up to 800 gallons makes it a good value for those who want to maintain their diesel vehicles regularly. The product is somewhat heavier and larger than some other additives, which could be less convenient if you prefer smaller bottles for storage.

With positive feedback from many users, this treatment is well-suited for diesel vehicle owners who want an all-in-one additive that improves power, protects fuel systems, and enhances fuel stability without having to buy multiple products.

Hot Shot's Secret Diesel Extreme Clean and Boost is designed to cover several important needs for diesel engines. It effectively cleans the fuel tank, lines, and injectors, which helps improve engine performance by removing buildup that can clog the system. It also removes free water from the fuel system, which is key to preventing corrosion and engine damage. The additive works to stabilize fuel, keeping it fresh for longer periods, which is useful if you don’t use your diesel often.

It provides a cetane boost, helping the fuel ignite more easily for smoother starts and better combustion. Additionally, it lubricates the fuel pump and injectors, reducing wear and extending their lifespan. The product comes in a 64 fl. oz. bottle, which is a convenient size for multiple treatments. It is not explicitly marketed as a performance enhancer beyond cleaning and boosting cetane, so if you’re looking for additives that improve power or fuel economy significantly, you might want to consider that.

With a strong customer rating and a well-established brand, this additive is a solid choice for diesel vehicle owners looking for reliable cleaning, lubrication, and fuel stability.

The Hot Shot's Secret LX4 Lubricity Extreme is a versatile diesel additive that shines in enhancing engine performance and extending the life of fuel systems. Its ability to increase fuel lubricity by up to 56% is a standout feature, providing critical protection against wear and tear on fuel pumps and injectors, especially in ultra-low sulfur diesel (ULSD) environments. This is particularly beneficial for users looking to maintain their vehicles in optimal condition, whether they drive gasoline or diesel engines. The product is designed to lubricate upper cylinders and other vital components, effectively reducing friction and improving engine performance. Plus, it’s easy to use—with just 1 ounce of LX4 for every 10 gallons of fuel, it integrates seamlessly into regular fueling routines.

While the LX4 is safe for all engine types, it may be less effective in very harsh fuel conditions or extreme temperatures. It acts as an excellent lubricant, but it may not provide the complete range of benefits seen in other specialized additives, such as comprehensive injector cleaning or anti-gel properties. Users who frequently operate in extreme cold may need to look for additives specifically designed to prevent fuel gelling.

For those looking to enhance engine performance, protect their fuel systems, and simplify maintenance, Hot Shot's Secret LX4 is a strong contender in the diesel additive category. However, if your vehicle operates under very harsh conditions or extreme temperatures, you might want to consider additional options to fully meet your needs.