FYI

It used to be spelled AMZOIL.

But the big yellow oil company sued them for using the zoil claiming they had it trademark. The name AMZOIL was derived from the founders neame A.J. Amatuzio

It was rumored the reason the suit was brough was the they were trying to buy out the Amzoil company and he would not sell. So in order to keep from loosing everything fighting a big oil company who had more lawyers than Amzoil had dealers, they agreed to change the name to Amsoil and get on with business.