Roger I haven't had much luck on the seldom used vehicles with stable, as I think it only adds 6 months of stability if I remember the packaging details. California adds a bunch of products to gas here that make our gas difficult to store long term, and also cause trouble in the 89 Softail Harley if tank isn't full with eating tank liner out of tank. Must be oxidative process due to too much air in half filled tank? Anyway after a winter project of going after the Harley carb issues with Stable in the gas tank, I switched to adding SeaFoam as additive instead. Seaform can protect up to a year or more, is completely combustible and does an amazing job dissolving particulate gunk from jets, and carb floats. What caught my attention with this product was the carb specialist from Mikes carburetors online and his accolades for the the specific ethanol protection from this product. It seems from this add it is much more cost effective as well as has the most benefits of all the products it was compared with. I figure it's worth a try! I will give feed back as the year progresses on it