In 1955 the 92 was reworked and became the 93. The engine was upgraded from two to three cylinders but unusually remained a two stroke. The car received a facelift, including the first Saab with the brand’s trademark trapezoidal grille. A wagon variant, the 95, was added in 1959 and would remain in production for the next twenty years. The decade also saw Saab's first foray into true performance cars with the Saab 94, the first of four Saab Sonetts.
The need for a larger model saw the birth of the Saab 99 in 1967. The 99 was the final Saab designed by Sixten Sason, who had designed all their earlier models. Its design, a clean break from all earlier Saabs, would mark the brand's styling for the next twenty years. The 99 was also important in that it marked Saab's first turbocharged model.
In 1970, the 500,000th Saab was built. Six years later the 1,000,000th would follow.
Saab signed an agreement with Fiat in 1978 to sell a rebadged Lancia Delta as the Saab 600 and jointly develop a new car platform. The agreement yielded the Alfa Romeo 164, Fiat Croma, Lancia Thema and Saab 9000, all riding atop the Type Four chassis.
In 1987 the 2,000,000th Saab was manufactured. However, the company began to struggle and to cut costs, the Arlöv plant was closed, but heavy financial losses continued. On 15 March 1990, General Motors bought 50% of Saab for US $600 million, with an option to acquire the remaining shares within a decade. Despite this, losses continued and the Malmö plant was closed in 1991.
GM's involvement spurred the launch of the "new generation" Saab 900 in 1993. The new car used the same platform as the Opel Vectra and polarized Saab aficionados, but thanks to its sales, the company declared a profit in 1995 for the first time in seven years. In 2000, GM purchased the remaining shares of Saab, making the company a wholly-owned subsidiary.
In March 2005, it was announced that GM would move the production of the next-generation Saab 9-5 from Trollhättan to the Opel plant in Rüsselsheim, Germany in 2009. The Trollhättan factory now produces European Cadillacs. The next-generation Saab 9-3 is scheduled to be produced at Trollhättan.