The white gel is most likely ethanol. In my experience, treating gas with Stabol before stowing equipment (or in your case a truck), is not an effective way to insure it won’t coagulate. Ethanol can gel in as little as six weeks. That means that you have to go thru a full tank in less that six weeks to insure you won’t have an issue. Fortunately, in my area, I can buy non-ethanol gas at about sixty cents more a gallon. I made the switch to non-ethanol treated gas several years ago when I was cleaning out several carburetors a year, in my 4-wheeler, snow blower and yard equipment. I did use Stabol when stowing my equipment over the winter/summer. Since I made the switch, I buy nothing but ethanol free gas and I still treat it with Stabol 360 prior to filling the can. That way, I don’t have to keep track of which equipment was treated. Since the switch, I virtually eliminated cleaning carburetors. I still run E-10 in my daily driver but I go thru more than tank of gas every two weeks.
You gas tank more than likely contains more of that gel and will need to be cleaned out in addition to the lines, petcock etc.
Last edited by Phak1; 06/20/2020 12:31 PM.