GM told Reuters on Wednesday that the current SRX will continue to be assembled in Mexico for an unspecified period of time after the new SRX begins production in Spring Hill. GM said a year ago it planned to invest $350 million in the Spring Hill plant, which was built originally for GM's now-defunct Saturn brand. At the time, GM said the Spring Hill plant would be retooled to build two new midsize crossover vehicles. In addition to the new SRX, the plant is expected to build a replacement for the GMC Acadia, according to the source, who spoke on condition of anonymity. On Wednesday, GM said it will invest another $185 million to build a new class of engine in Spring Hill. The engine plant will retain about 390 jobs, GM said. The retooled vehicle assembly plant will require about 1,800 hourly workers, GM said. The Spring Hill complex currently employs just over 2,000 hourly and contract workers in vehicle and engine assembly, stamping and molding operations.