Detroit (TheStreet) -- GM (GM - Get Report) said sales in May rose a surprisingly strong 13%, leading to the automaker's best month since August 2008 despite widespread publicity surrounding its 13.6 million U.S. recalls so far this year.

Chrysler sales rose 17%, while Ford (F - Get Report)said sales gained 3%. The auto industry easily surpassed expectations, as GM estimated the seasonally adjusted annualized sales rate at 16.5 million while Chrysler estimated 16.9 million. Most experts had estimated 16.1 million.

The double-digit gains were partially due to a May that included five weekends.

GM said it expects its market share to increase. The automaker delivered 284,694 vehicles as retail sales gained 10% and fleet sales rose 21%.

"The momentum we generated in April carried into May, with all four brands performing well in a growing economy and 17 vehicle lines posting double-digit retail sales increases or better," said Kurt McNeil, U.S. vice president of sales operations, in a prepared statement.

May will likely represent the highest fleet volume month of the year, due to the timing of rental customer deliveries, GM said, noting that June fleet sales likely will decline sharply.

Chevrolet sales rose 14% to 205,010 as car sales rose 26%. Cruze sales rose 41% to 32,393. Silverado sales rose 8% to 46,648. Malibu sales rose 2% to 19,288. Impala sales rose 23% to 13,348.

Buick sales rose 11% to 19,957. GMC sales rose 8% to 45,039. Cadillac sales rose 6.4% to 14,688.

Ford said sales rose 3% to 254,084 units. Retail sales rose 6% to 174,889. Fusion sales rose 14.5% to 33,881.

F-Series sales rose 4.3% to 68,520. Escape sales rose 9.5% to 31,896. "Fusion and Escape had their best months ever, which helped us to our strongest May result since May 2004," said John Felice, vice president for U.S. marketing, sales and service.

Chrysler said it sold 194,421 vehicles, its best May since 2007 and its 50th consecutive month of year-over-year sales gains. Jeep sales rose 58% to 70,203, its best sales month ever for the third consecutive month, while Ram pickup sales rose 17% to 37,131, its best May since 2005. Chrysler brand sales lost 22% to 22,592, as Chrysler 200 sales fell 76% to 3,140 as production of the 2014 model ceased.

"Our Jeep sport-utility vehicles and Ram pickups continued to do well in May as our dealers reported brisk May sales over five weekends and the Memorial Day holiday," said Reid Bigland, head of U.S. sales, in a prepared statement.

-- Written by Ted Reed in Charlotte, N.C.

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