I will give you an example in my own personal vehicle. I was initially getting 22 MPG on the highway with my car with conventional oils. I switched over my engine, transmission and rear differential over to Amsoil's synthetics.       

       Afterwards, I realized a gain of 4 MPG due to the reduced friction of the synthetics. I paid approximately $250 (including labor costs) to have all of my fluids changed over. That change over lasts up to 1 year on the oil and several years for the other fluids. At the time of my tests, fuel was $3.19/gallon for premium that I was using. That same $250 is close to what I would pay for a year’s worth of oil changes at a quick lube for conventional oil, but with conventional oil, I’d still be getting 22 MPG, not the 4 MPG increase from synthetics.

Company Resource:    Ground Source Heat Pump, Industrial Air Conditioner, Air Source Heat Pump, 
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