i was told by a mechanic i trust that marvel mystery oil is as good as anything out there and is very cost efficient. i've been adding 8oz. to each 20 gals.of gas and have had no problems. i put it in my older cars as well, seems to keep things running well.
How often are you running this thru? With each tank up or less frequently? I have not used Ethanol gas yet but looks like this year I will be. Just curious as I have an I/O with a Chevy engine.
