The 1971 Chevrolet Vega was GM's launch into the new subcompact class to compete against the import's increasing market share. Problems associated with its innovative aluminum engine led to the model's discontinuation after seven model years in 1977. During the late 1970s, GM would initiate a wave of downsizing starting with the Chevrolet Caprice which was reborn into what was the size of the Chevrolet Chevelle, the Malibu would be the size of the Nova, and the Nova was replaced by the troubled front-wheel drive Chevrolet Citation. In 1976, Chevrolet came out with the rear-wheel drive sub compact Chevette.