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E85 Fleet Toolkit

Equipment Conversions

Photo of a hand holding an E85 fueling nozzle.

It may be possible to convert existing gasoline or diesel fueling tanks for use with E85. Most metal underground storage tanks that meet U.S. Environmental Protection Agency (EPA) December 1998 codes can be used to store E85.

Many underground fiberglass tanks that meet EPA standards may also be used to store E85. However, we caution fuel site operators on using E85 with single-walled fiberglass tanks manufactured before 1992. Most fiberglass tanks in use in the United States are double-walled. If you have questions concerning the use of E85 in older fiberglass tank, you may wish to contact the Fiberglass Tank and Pipe Institute for their recommendations.

We have included the following letters from fiberglass tank manufacturers that outline their recommendations for ethanol fuel storage. The following documents are available as Adobe Acrobat PDFs. Download Adobe Reader.

  • Owens-Corning Fiberglass Corporation Letter (PDF 75 KB)
  • Underwriters Laboratories Inc. Letter (PDF 145 KB)

Important: Cleaning the tank before introducing E85
If another fuel was stored in the fueling system that you intend to convert to E85, the system must be properly cleaned. Years of fuel storage can result in sludge, moisture, and scale buildup. Even an inadvertent "oops" by a transport driver can result in dirt or snow falling into the storage tank during fuel delivery. Pens, loose change, eyeglasses and cell phones have all ended up in the bottom of fuel tanks. These are all potential sources of fuel contamination. Introducing ethanol-blended fuel, which will act as a cleaning agent, into such a tank will contaminate your fuel and may result in vehicle operational problems. This concern will be diminished if a low-level blend of ethanol, such as 10% ethanol or E10, has been stored in the tank.

If an existing metal or fiberglass storage tank will be used to store E85, the process in the link below should be followed to ensure that potential contamination is removed.

Learn more about the process for converting a petroleum system to an E85 compatible system.