AFC Diesel Fuel Additive
Cleans Fuel Tanks, Dissolves Sludge

Avoid Expensive Tank Removal
and Disposal of Contaminated Fuel


  • Clogged and Slimy Filters

  • Dark, Hazy Fuel

  • Floating Debris in Tanks

  • Sludge Build-up in Tanks

  • Loss of Power and RPM

  • Excessive Exhaust Smoke

  • Corroded, Pitted Fuel Injectors

  • Foul Odor Emitting from Fuel Tank

Fuel tank sludge accumulates over a period of time when the conditions in the tank are right. The older your fuel tank, the more likely you will have an accumulation of water (required for microbial contamination to grow), rust, particulates, sludge, and what is commonly referred to as fuel algae, a byproduct of the microbial contamination that is drawn in through the tank vent or picked up at a fuel source that has the contamination.

AFC-705 Tank Cleaning Additive

AFC is a broad spectrum fuel additive and diesel catalyst that will dissolve the debris, sludge, and organic growth from your tank that clogs fuel filters and plugs fuel injectors on new and old diesel engines.

Fuel system sludge is a big problem with today’s common-rail fuel systems as the tolerances are so small, requiring 4-micron filters. See the article Diesel Fuel & Injector Failures on this web site to understand fuel cleanliness specifications and why bad diesel fuel will dramatically shorten the life of your fuel injectors.

Most fuel additives on the shelves of your local truck stop do not clean diesel fuel tanks. They just don’t have the additive components needed to deal with the heavy sludge, floating organic materials (algae) and water that accumulates in the bottom of a tank.

Fuel Clarity Comparison

If tank access is readily available, portable and mobile (cart mounted) tank cleaning systems are available to clean tanks without the need to remove the tank from the truck or other equipment. You don’t need to pressure wash or steam clean the inside of the tank, and will not have the expense of disposing of your fuel, although that is what is typically recommended by mechanics and equipment dealerships.

If easy access to the tank is not available, use of AFC will clean your tank, although the process may require several treatments as you use the equipment. When cleaning your fuel tank, first remove any water from the tank bottom with a hand pump if possible. Fill the fuel tank (you don’t want to clean just the bottom half of the tank). Add one 8 oz. bottle of AFC for each 160 gallons of fuel. Allow the additive to stay in the tank overnight to “soak” the sludge.

Contaminated Fuel

If you have a portable tank cleaning system, or have a fuel pump and filter that can circulate the fuel, the process will go much faster. Fuel Polishing Systems incorporate a Fuel Conditioner that will further dissolve sludge and biomass (which includes heavy fuel components, such as asphaltenes, that have agglomerated and come out of solution, causing fuel to appear brown or black).

Some equipment, such as motorhomes, diesel pickups, etc. do not allow for inserting hoses into the tank to circulate the fuel. That’s ok. Just run the equipment as normal. However, the sludge and organic debris does not just disappear. The AFC will break it down and much of it will dissolve and pass through the fuel filter and be expended in the combustion process. Some of the debris will get into your fuel filter, so be prepared to change out your filter when it gets full. That’s what it’s there for!

AFC is available in three versions:

  • AFC-705 is for pre-2007 diesel engines

  • AFC-710 is for 2007 and newer engines (Tier 4 compliant)

  • AFC-805 has the same tank cleaning characteristics as AFC-705 and 710, and includes a cold-weather component that makes it ideal for bulk fuel farms (continuing to work for up to 12 months) and in other cold weather applications

TK-240 XT Portable Tank Cleaning System

TK-240 XT Portable
Tank Cleaning

Note we do not recommend the use of biocides as these chemicals will transform the organic materials into a grit that will get stirred up each time fuel is added to the tank and will continue to clog the filters. An inline Fuel Conditioner will permanently solve this problem and polish the fuel as the equipment operates.

All three variations of AFC Diesel Fuel Additive & Diesel Catalyst is available in 8-oz bottles, one gallons jugs, 5-gallon pails, and 55-gallon drums. For preventative maintenance continued use, one 8 oz bottle treats 320 gallons, and one gallon treats 5,000 gallons. After your tank is clean, use AFC every 6 to 12 months.

Contact us to discuss your diesel fuel maintenance requirements. Since 1996 we have helped individuals and companies identify and solve existing and potential fuel problems, removing that last weak link from enjoying uninterrupted peace of mind.