 By the end of the decade, Ziebart had increased the number of franchised locations worldwide to over 650, while at the same time doubling the retail volume of US franchisees.In 1980, Ziebart began to diversify its business format and its service offerings by including sunroofs, running boards, window tinting and other automotive accessories.All American Motors cars received a new rust-proofing process called "Ziebart Factory Rust Protection".