Actual fuel economy will vary depending on the vehicle. Once again I know a little bit about cars. They can't guarantee anybody they are going to save a specific amount of gas they can only estimate like car manufactures estimate gas mileage for cars they produce.
Have you ever seen or heard of a car manufacture guaranteeing a specific mileage per gallon for a vehicle. No, they give a range. The Aero muffler will save fuel but it will depend on the age/mileage of the vehicle the type of vehicle and the driver. The car manufactures understand this that is why it is an estimated miles per gallon and they usually follow that with a disclaimer that your actual mileage could vary.
make claim that the AERO turbine saved on fuel consumption and has stated so for 4 years. I is in print on there patent. See ref. and link. Get those facts right and try again
Patent #6679351, US Patent Issued on January 20, 2004.
"Various tests have been conducted using an air turbine device in accordance with the principle invention with surprising results. An air turbine device was installed on a Kenworth 525 CAT Cummins N14 diesel engine in a muffler configuration. That is, the air turbine device was installed on the exhaust in replacement of a stock muffler. The average gas mileage of the engine using the stock muffler was 5.7 MPG. After installation of an air turbine muffler in accordance with the present invention with no other modification to the engine the following results compiled in TABLE I were achieved.
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