On Tuesday morning, March auto sales came in at levels not seen since May of 2007.
General Motors' March sales were up 6 percent year-over-year "thanks to a strengthening economy and new products," said Kurt McNeil, GM's vice president of U.S. sales operations. Pick-up trucks have been particularly strong, as contractors and other businesses start to replace aging fleets.
(Read More: Buckle Up: Auto Sales Surge in March)
Despite the strength, which was in-line with expectations, shares of GM dropped Tuesday morning. This prompted some traders to step in and buy upside calls into the weakness. The biggest trade of the morning was the purchase of 1255 May 29-strike calls for $0.55, which was done with the stock at $27.60. This is a bullish bet that the stock will be above $29.55, or 7 percent higher, come May expiration.