the amc eagle was the first production car to use the complete "ferguson formula" (ff) full-time all-wheel-drive system from britain's ferguson research. other four-wheel-drive automobile-type vehicles – the subaru dl/gl (1972 for the japanese domestic market and two years later in the u.s.), and much later the toyota tercel sr5 wagon (1983) - only had part-time four-wheel-drive systems that could not be engaged on dry pavement. the eagle was also years ahead of subaru's simplistic, part-time front-drive/4wd system, due to roy lunn's creativity and jeep's experience producing 4wd vehicles. another feature was the eagle's independent front suspension, accomplished by mounting the front differential to the engine block with universal joints and half shafts to drive the front wheels.