If they're gasoline-resistant, it won't hurt to try. Throw one in a (closed) jar of gas overnight. It may swell noticeably, but if it turns gooey or turns the gas dark, don't put it in the truck. If you leave it out in the sun for a day or 2, it'll shrink back down as the gas evaporates out of it. Use only clean engine oil to lubricate the o-rings for assembly.