General Motors ( GM) regained its position as the world's largest automaker over the summer, with its closest rival, Toyota ( TM) reporting third-quarter sales volume that fell short of its Detroit counterpart. After selling more vehicles than GM in the first half of the year, Toyota said it sold 2.34 million vehicles in the July to September quarter. GM sold 2.38 million vehicles in the period. That put Toyota in second place for the first nine months of the year, with 7.05 million global sales, compared with GM's 7.06 million. The tally amounts to one more victory for GM this year as it strives to turn around its fortunes after a disastrous performance in 2005. The company recently reached a historic deal with the United Auto Workers to revamp its labor and legacy cost structure -- a major albatross for Detroit's auto industry as it struggles to stay competitive in the age of globalization. Shares of GM recently crossed the $40-mark for the first time in nearly three years, though they lost ground last week amid turbulence in the broader stock market. The stock recently was up 81 cents, or 2.1%, to $39.49. Despite the victories, GM still faces daunting challenges. With oil prices flirting with $90-a-barrel, consumers are expected to gravitate further towards smaller, fuel-efficient cars and Asian auto manufacturers like Toyota still dominate that market. Furthermore, the U.S. economy is showing signs of fatigue, particularly in consumer spending, as an epic housing slump takes its toll. Auto sales in the U.S. are expected to be a casualty, casting a pall over GM's ability to extend its rally. Analysts have predicted for years that Toyota would overtake GM in global sales volume, but for now, the world's largest automaker still resides in Detroit.