so I thought if tossed into a larger tank like my "32 gal. Suburban" and mixed with the correct fuel it would be okay, but if you say no I will toss it in a few months if they don't burn it up.
MY 2003 Dodge Dakota has a 24 gallon tank and I have thrown a gallon or two of mixed two stroke fuel in it a couple of times over the years. (100 octane at 32:1) Have never seen any issues when doing it. Take the two stroke mix with me to the gas station when the truck is empty, pour in the mixed fuel, then fill the truck from the pump. Figure a full tank dilutes it down enough that there really isn't much oil in it. For sure wouldn't do it every week, but I figure once a year won't hurt. (I have probably only done it four times in teh 9 years I have owned my truck.) I would probably take the 3.5 gallons you have and split it up over two tanks, that way it is really diluted.
As a side, I have run a bunch of mixed two stroke in my four stroke lawnmower, don't dilute it or anything, just pour it right in. I figured I would smoke some but it doesn't, I can't notice any difference in the way it runs. It sure does smell good though while I mow the lawn!
Doug