I've used it -had a 5 gallon pail and I could tell the difference in carbureted engines more than fuel injected on an ongoing basis.
Used it in my 03 F-150 and the initial increase in MPG was significant but remained flat on an ongoing basis.
On my lawn mower it always took 2 tanks of gas and when I used the SoyUltra I usually used 1.5 tanks. I purposely left out it out on some tanks of gas and went back to using 2 tanks.
I'm on the Nuetra right now and noticing it works differently, more cleaning of the fuel system in my opinion.
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