The ONLY diesel treatment to restore the entire fuel system
AR6500 is the only product to deliver a complete clean and boost package to the entire fuel system and post-combustion system (turbo, DPF) to protect your engine, improve performance and maximize fuel economy.

Clean the DPF to reduce regens and avoid failure
Unlike other additives, AR6500 Diesel Treatment cleans carbon build-up from the diesel particulate filter (DPF). A clean DPF is essential for maintaining performance, reducing emissions and improving fuel efficiency.
AR6500 removes build-up and keeps the DPF free from heavy carbon deposits to:
- Reduce regeneration frequency
- Restore MPG & performance
- Avoid engine damage by preventing a clogged DPF

Boost Cetane & Increase MPG
AR6500 incorporates a strong cetane boost and Archoil's proven combustion modifier technology to increase power and response at every fill-up.
By increasing the cetane rating of diesel alongside the cleaning properties of AR6500, combustion efficiency and fuel economy are improved which means less stops at the gas station, saving you up to $174 per 40.6 oz bottle of AR6500 (based on 10% MPG increase and average fuel prices January 2024).

Improve Fuel Lubricity
AR6500 improves the lubricity of diesel fuel. Lack of lubrication can cause a variety of issues in both older vehicles which weren't built to run on ultra low sulfur diesel and new vehicles which are built with tighter tolerances, making a lack of lubricity potentially catastrophic. These issues include:
• Excessive wear
• Premature failure
• Costly repairs
The Engine Manufacturer's Association (EMA) recommends using fuel that produces a wear scar no larger than 460 microns to meet the needs of a vehicle. The diesel fuel specification in the United States (D-975) is only 520 microns, meaning additional lubricity must be added to meet the EMA recommendation - highlighting the importance of diesel fuel additives.
In wear scar testing (ASTM D6079), base diesel fuel produced an out-of-spec scar width of 614.5 microns. The same fuel treated with AR6500 produced a scar width of 347.5 microns - a 43% increase in lubricity. Improving lubricity extends the life of components, including the CP4, and prevents premature failure.

Clean Fuel System Components
Poor or incomplete combustion is one of the primary factors affecting the power and performance of your vehicle. As a result of low cetane fuel and a lack of detergents and lubricity, diesel fuel systems accumulate soot and carbon build-up in the key components including the injectors, turbo and DPF.
AR6500 contains the detergents, lubricity and cetane boost your vehicles requires to clean and maintain the fuel system.
Use of AR6500:
• Removes carbon injector deposits to restore spray patterns
• Prevents turbo lag and restores boost
• Reduces frequency of DPF regenerations
This easy, proactive maintenance of the fuel system restores lost horsepower and fuel economy and extends component life.

Remove Heavy Carbon Build-up
Vehicles with high mileage or symptoms of a restricted fuel system (including smoking, poor fuel economy, turbo lag and frequent regens) should be treated with Archoil AR6400-D Diesel Fuel System Cleaner first to speed up the process of cleaning the fuel system and remove heavier carbon deposits.
AR6400-D is a powerful, one-tank treatment developed to rapidly restore performance which rapidly cleans injectors, turbos and DPFs to remove performance-robbing carbon build-up.
The Diesel Fuel System Kit includes AR6400-D and AR6500 to maximize fuel system performance.
AR6500 FAQs
AR6500 improves lubricity in fuel, cleans and maintains the fuel system and adds cetane for a boost that can be felt at every fill-up. AR6400-D is a highly concentrated one-tank fuel system cleaner to be used every 5,000 miles for rapid cleaning of heavy carbon build-up.
AR6500 is suitable for all diesel vehicles, including newer systems such as High Pressure Common Rail.
AR6500 will remain stable indefinitely if kept away from sources of heat and sunlight.
No, AR6300 Winter Diesel Treatment is the product you need for cold weather. AR6300 contains all the benefits of AR6500 plus anti-gel protection up to -44ºF.