 Cooper Tire Rubber Co. said Monday that its tire manufacturing plant in El Salto, Mexico will restart production, on a limited basis. The company had reopened its Mexico plant on April 13, only to have to shut it back down on April 28 after the Mexico government determined it was a non-essential business. The tire maker said its plants in China, the U.S. and Serbia have all reopened. The stock, which was little changed in premarket trading, has gained 0.9 over the past three months, while the SP; 500 has tacked on 3.1. 