Dana Corp. which recently announced an agreement to divest its aftermarket business, credited strong sales in the North American heavy-truck market with helping double the company’s second-quarter profits. Dana also received a $33 million boost in tax benefits from the sale of its automotive aftermarket business. The company earned $108 million, or 72 cents per share, in the second quarter compared with $52 million, or 35 cents per share, for the same period a year ago. Excluding one-time items, the company earned 49 cents per share, matching expectations of analysts surveyed by Thomson First Call. Sales for the quarter were $2.3 billion, an increase from $2 billion a year ago. The company’s stock rose $1.33, or 7 percent, to $19.58 in morning trading on the New York Stock Exchange. All figures in U.S. dollars. Dana announced two weeks ago that it had reached a deal to sell its replacement parts unit for $1.1 billion in cash to a New York-based equity group, The Cypress Group. The sale of the Automotive Aftermarket Group included 52 plants worldwide that employ about 13,000 people. The business had sales of about $2 billion in 2003, or about a quarter of Dana’s overall annual sales. The Toledo-based company plans to use money from the sale to reinvest in its core businesses, reduce debt and add to its pension plans. Dana employs 45,000 people worldwide.