Arvin Industries Inc. will sell Magneti Marelli SpA its shares in a ride-control operation in Melfi, Italy, while Magneti Marelli, through its Brazilian affiliate Cofap, transfers its 60% share in the Cofap-Arvin joint venture to Arvin . . . Siemens Automotive begins expanding its North American headquarters in Auburn Hills, MI, and opens an engineering and sales office in Dearborn, MI, to support growing business withMotor Co. . . . Echlin Inc. will become a subsidiary of Corp. now that shareholders of both companies have approved the deal . . . SPX Corp., which lost its bid to take over Echlin, has acquired Tecnotest Srl, of Parma, Italy, a supplier of electronic and emissions testing equipment with 100 employees . . . Dana sells its hydraulic cylinder business to Hyco International Inc. of Atlanta. The unit recorded $73 million in sales in 1997.