American Power Group Receives Approval for Additional OUL Vehicular Engine Family Applications; Total Approvals Now at 110 Engine Families

LYNNFIELD, MA--(Marketwire - Mar 4, 2013) -   American Power Group Corporation (OTCQB: APGI), announced today that its subsidiary, American Power Group, Inc. ("APG"), has received online notification from the U.S. Environmental Protection Agency ("EPA") that its recent Clean Alternative Fuel Vehicle and Engine Conversion Submission for an additional 22 engine families has been approved for the following additional Outside Useful Life ("OUL") engines:

• Cummins ISX (2009 - 2007)
• Cummins ISM (2009 - 2007)
• Caterpillar C-15 (1997 - 1996)
• Caterpillar C-16 (1997)

The submission utilized APG's latest V5000 Dual Fuel Turbocharged Natural Gas™ technology which is required to meet specific design, componentry, and emission compliance criteria per the EPA Final Rule 40CFR Parts 85 and 86.

Lyle Jensen, American Power Group Corporation's President and Chief Executive Officer, stated, "This round of approvals mark the completion of the Class 8 EPA OUL testing for the most popular Cummins and Detroit Diesel engine families for model years 2009 to 2002 and the most popular Caterpillar engine families from 2006 to 1996. Caterpillar exited the vehicular engine market after 2006. The EPA OUL testing for the Volvo and Mack engine families has begun and we anticipate testing and approvals to be completed within the next 60 to 90 days. Following that, we will wrap up our EPA OUL testing with selected engine models older than model year 2002 for the re-manufactured engine conversion market and the International DT 466/MaxxForce engine series. Since May 2012, we have received approval on over one hundred EPA OUL engine families and anticipate having over two hundred OUL engine families approved when we complete this phase of testing later this spring which would open up an estimated domestic multi-billion dollar OUL addressable market of 500,000 vehicles."

Mr. Jensen added, "We also have begun our EPA Intermediate Useful Life ('IUL') testing at the University of Houston Diesel Testing And Research Center for the lower mileage Class 8 trucks that utilize either the catalytic convertor or selective catalyst reduction emission technology. Progress is steady and we expect most of the popular IUL engine family approvals will be completed during the calendar year representing an estimated additional 400,000 potential vehicles for dual fuel conversion. This timeline aligns itself nicely with our recently announced national roll-out of WheelTime Network certified installers which will occur during calendar year 2013."

About American Power Group Corporation
American Power Group's alternative energy subsidiary, American Power Group, Inc., provides a cost-effective patented Turbocharged Natural Gas™ conversion technology for vehicular, stationary and off-road mobile diesel engines. American Power Group's dual fuel technology is a unique non-invasive energy enhancement system that converts existing diesel engines into more efficient and environmentally friendly engines that have the flexibility to run on: (1) diesel fuel and liquefied natural gas; (2) diesel fuel and compressed natural gas; (3) diesel fuel and pipeline or well-head gas; and (4) diesel fuel and bio-methane, with the flexibility to return to 100% diesel fuel operation at any time. The proprietary technology seamlessly displaces up to 80% of the normal diesel fuel consumption with the average displacement ranging from 40% to 65%. The energized fuel balance is maintained with a proprietary read-only electronic controller system ensuring the engines operate at original equipment manufacturers' specified temperatures and pressures. Installation on a wide variety of engine models and end-market applications require no engine modifications unlike the more expensive invasive fuel-injected systems in the market. See additional information at: www.americanpowergroupinc.com.

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