“Mr. Kibler, my name is [so-and-so] and I have a fuel additive which will save the City thousands of dollars per year on fuel costs.” In the past 40 years, I’ve heard that promise at least 200 times and can honestly say after testing countless “guaranteed” fuel saving additives and devices, not one increased the MPG on any vehicle we’ve tested. The sad reality in each of these instances is the salesperson completely believed in their product and was certain their promised improvement would happen.

To be courteous and open minded, we must be professional and hear the salespeople out. Here’s how I respond. We inform the salespeople that we will not buy any system or additives unless they prove the performance promised in our agencies’ work environment. The salesperson must supply, at their cost, two devices or enough additive to complete a multi-tank test on two different vehicles. The City would administer the test without informing any of the operators a test was being conducted. (We stopped informing operators because through the power of suggestion, operators unconsciously improve their driving habits and get better mileage) Most tests were run for at least three tanks of fuel. We would record average MPG before and during the test. Results have never (in our case) resulted in improved MPG on any vehicle tested. After seeing the results of our tests, salespeople always responded: “I just don’t understand why it didn’t work.”

Here is what the salespeople may not have understood:
How does an additive actually improve MPG?
o By keeping the combustion chamber and fuel components clean of power robbing carbon deposits. Most chemicals which accomplish this are too expensive to generate any return on investment. They are simply a good PM conditioner to keep the vehicle running better, thus improving economy slightly.
o By increasing the net BTU’s of the fuel combustion mixture. Most additives which promise this are mixed with mineral oil which coincidentally slows down combustion and increases BTU yield. It’s actually the oil, not the additive which helps MPG. (Altering the chemical content of fuel may be illegal in most states)
Under what driving condition are they designed to work best?
o At highway speeds. When you look at the case studies presented as supporting documentation, they are always over-the-road applications. A Municipality fleet vehicle seldom achieves normal operating temperature before arriving at the work site.

Of all the gimmick devices and additives from salespeople I met with, my favorite was a fuel-line camp-on magnetic device called “Neodymium Fuel Saver” which claimed to “align all the fuel molecules so that fuel mixtures were highly concentrated and would generate more horsepower, using less fuel.” We tested that one on two identical G3500 gas school buses; we told one driver about it and not the other. The driver we told improved her fuel economy by 3 MPG. The uninformed driver showed zero MPG improvement. You may recall a discovery claimed by farmer’s years ago that two cow magnets taped around the fuel line would increase your fuel mileage by aligning fuel molecules so that they burn more uniformly. (Yep – another one for Myth Busters) Improved MPG occurred because through the power of suggestion, driving behavior changed. Why is this a myth? Magnetic fields do two things: affect ferrous metal and generate current. It has no effect on hydrocarbon – duh!

The most informative fuel additive article I’ve ever read was “The truth about fuel additives” by Sean Kilcarr in FLEETOWNER magazine (August 2012). I highly recommend this article.

Have you got any snake oil stories you’re willing to share?

Originally posted on Automotive Fleet

About the author
Steve Kibler

Steve Kibler

Fleet Manager

Born to rural Iowa, Steve was trained at an early age that nothing was free for the asking. If you wanted something you had to make it a goal and work for it. Even as a toddler, Steve immediately had a talent for taking anything apart.

View Bio