If it works, why not use it? It sure is better for the owner to keep his car and remedy the problem, than tear down the engine, or sell it for usually a large financial loss. Over charging the customer in price, is another matter for Z-MAX.
Just a point of information on Marvel Mystery Oil, Buick Engineers, developed it for upper cylinder lubrication problems on engines, back in 1923, for all GM engines. It's still good to use today, on older cars after they have experienced some wear on their internal engine components. I use it and can honestly say it keeps my old cars running smoothly and I'm satisfied with it's performance and cost.
Just a point of information on Marvel Mystery Oil, Buick Engineers, developed it for upper cylinder lubrication problems on engines, back in 1923, for all GM engines. It's still good to use today, on older cars after they have experienced some wear on their internal engine components. I use it and can honestly say it keeps my old cars running smoothly and I'm satisfied with it's performance and cost.
