10 Best Auto Fuel Additives 2025 in the United States

The Lucas Oil Fuel Additive is designed to clean and lubricate the fuel system for both gasoline and diesel engines, making it a versatile choice for cars and trucks. It acts as a tune-up in a bottle by neutralizing issues related to low sulfur fuels and helping to extend the life of important engine parts like pumps and injectors. Users often see benefits such as increased power and better fuel efficiency because it helps burn excess exhaust emissions.

This product comes in a large 1-gallon jug and is sold in a set of four, which is convenient if you plan regular use or have multiple vehicles. Its universal fit means it should work well with most engines, so compatibility is broad. The brand, Lucas Oil, has a strong reputation.

If you want a reliable additive that supports engine health and efficiency and prefer buying from a trusted brand, Lucas Oil Fuel Additive is a solid option. For most drivers, this product offers a straightforward and effective fuel system treatment.

Techron Concentrate Plus Fuel System Cleaner by Chevron is a strong choice if you're looking to keep your vehicle's fuel system clean and running smoothly. It targets key trouble spots like fuel injectors, carburetors, and combustion chambers, helping to restore lost power, improve acceleration, and even stabilize fuel for up to a year. It’s compatible with a wide range of gasoline engines—from cars and trucks to motorcycles and boats—which makes it versatile for different users.

The product is concentrated, so you only need to use it every 3,000 miles for cars and trucks, or as needed for other engines, which is convenient for regular maintenance. Chevron’s solid brand reputation and a high customer rating (4.6 out of 5 from over 15,000 reviews) suggest many users find it effective and trustworthy. On the downside, the 32 oz size is a one-time purchase that might seem pricey upfront, and while it helps reduce rough idling and hesitation, users with severe engine issues may need professional service.

If you want a reliable, easy-to-use additive to regularly clean and protect your fuel system and improve fuel efficiency, Techron Concentrate Plus is a dependable option that covers most gasoline engine types well.

The Red Line 60103 SI-1 Complete Fuel System Cleaner is a concentrated liquid additive designed to clean and protect your vehicle’s fuel system, including injectors, carburetors, valves, and combustion chambers. Compatible with most gasoline engines, it comes in a convenient 15-ounce bottle, with this pack containing two bottles. One bottle per tank is recommended, making it easy to use and effective in a single treatment.

This cleaner removes deposits such as gum and varnish, helping fuel burn more efficiently and stabilizing gasoline to prevent corrosion. The product is unscented and highly rated by users, reflecting strong brand reliability from Red Line, known for quality automotive additives. Though it is priced higher than basic fuel additives, its concentrated formula and thorough cleaning action make it a solid choice for drivers aiming to maintain engine performance and fuel economy. It is important to note that it is intended for gasoline engines and is not suitable for diesel vehicles.

Using this fuel system cleaner regularly as directed can help keep your fuel system in good condition, especially if your vehicle is prone to buildup or if you want to extend engine life.