1970 - New Mack World Headquarters opens in Allentown, Pennsylvania. 1975 - The Cruise-Liner, produced from 1975-1983, served as Macks premium offering in a cabover configuration. Macungie plant opens for business. The Engineering and Development and TestCenter was opened in Allentown, Pennsylvania. This 65 acre facility has capability to take ideas for vehicles or components through all the design and testing functions in one location. 1977 - The Super-Liner, a boldly-styled conventional designed for heavy hauling with the ultimate in driver luxury and convenience, was introduced in 1977. Its 15-year production run ended in 1993. 1978 - The MC/MR series, introduced in 1978, are the industry's most advanced low-cab-forward trucks with exceptional maneuverability and visibility for refuse, construction, and urban delivery applications. 1979 - Renault takes a 10 percent share in Mack Trucks, Inc.