The Palmetto State now claims to be the tire manufacturing capital of the U.S., after attracting billions in investment from Group Michelin, Bridgestone Corp. and Continental A.G. over the past 15 years, supplemented by hundreds of millions more in spending from Giti Tire Group and Trelleborg A.B. in plants to open over the next few years. With the start of production earlier this year by Continental at its plant in Sumter and expansions of capacity by Bridgestone and Michelin at multiple locations, estimated daily production in South Carolina has climbed to 89,000 units, according to Tire Business research, which surpasses Oklahoma by 1,000 units.