U.S. auto sales in September may have accelerated to the fastest rate since the federal government's 'cash for clunkers' incentive program last year as deliveries rose at the top seven sellers of vehicles in the nation. General Motors said Friday that industrywide U.S. sales in September may have increased to a rate of 12 million a year, and Chrysler said they gained to 11.9 million. Ford Motor Co. said deliveries were in the 'upper 11 million range.' The month's stronger sales are a sign that the car market and the broader economy may have bottomed out and that a slow, stable recovery is under way, said Jesse Toprak, vice president of industry trends for Santa Monica, Calif.-based TrueCar.com. Toprak said deliveries may have reached 11.9 million, up from his earlier estimate of 11.6 million. 'It's slightly better than expected, but it's still a stable and painful growth process,' Toprak said in an interview. 'This is another step in a healthy but rather slow recovery. This month, there were no outside forces at play, like government program or crazy incentives, just the marketplace trying to recover on its own.' Deliveries at GM, the largest U.S. automaker, climbed 11 percent from a year earlier to 173,155, the Detroit-based company said in a statement Friday. Ford, the second-largest, increased sales 41 percent to 160,873, the Dearborn, Mich.- based company said in a statement. Industrywide deliveries in September were expected to reach an 11.7 million rate, the average of nine analysts' estimates compiled by Bloomberg. That would top the 9.4 million pace of last September, the month after 'cash for clunkers' ended. Deliveries in all 2009 were 10.4 million, the lowest since 1982. The stronger month doesn't indicate renewed economic growth, just that the economy has avoided a double-dip recession, said John Canally, an economist and investment strategist at Boston-based LPL Financial Corp., which oversees $276.9 billion in assets. 'We probably have put a floor under vehicle sales, but the sparks you need to reaccelerate aren't quite there yet,' Canally said in an interview. 'You don't have robust job growth or robust income growth. Your traditional catalysts for strong consumer spending just aren't in place yet.' GM's deliveries trailed three analysts' average estimate for a 13 percent gain. Chevrolet brand sales rose 18 percent to 121,479, helped by the Silverado pickup and Equinox SUV. Buick deliveries gained 36 percent to 12,875, aided by the LaCrosse sedan. GMC increased 42 percent to 25,995, and Cadillac rose 11 percent to 12,620. 'Consumers are willing to spend, albeit cautiously,' Don Johnson, GM's vice president of U.S. sales, said Friday on a conference call with analysts. The industrywide selling rate for the month may be 12 million, he said. GM's sales of the Hummer, Pontiac, Saturn brands, which were closed, and the Saab brand that it sold, fell to 186 vehicles from 14,982 vehicles in September 2009. GM's four remaining U.S. brands _ Chevrolet, Cadillac, GMC and Buick _ rose a combined 22 percent in September. Ford's results topped six analysts' average estimate for a 40 percent gain. The company's namesake brand deliveries increased 49 percent to 147,057 vehicles, while Lincoln gained 26 percent to 7,510 and the Mercury line, which is being discontinued, rose 16 percent to 6,306. Excluding the Volvo line, which Ford sold to China's Zhejiang Geely Holding Group Co., sales rose 46 percent. Chrysler sales increased 61 percent to 100,077, the Auburn Hills, Mich.-based company said in a statement. That topped the 48 percent average estimate of six analysts surveyed by Bloomberg. Deliveries of its namesake brand rose 92 percent to 17,348, helped by the Town & Country minivan and Sebring sedan. The Dodge brand increased 71 percent to 36,272, Jeep rose 65 percent to 28,603, and Ram gained 22 percent to 17,854. 'Chrysler is benefitting from stable gas prices and the highly visible launch of the redesigned Grand Cherokee,' Ivan Drury, an analyst for Santa Monica, Calif.-based Edmunds.com, said in an e-mailed statement Friday. 'As long as consumers are not worried about high fuel costs Chrysler should be able to maintain a decent sales pace, since 71 percent of Chrysler sales are trucks.' 'We believe the economic recovery in the second half will be slower than the first half,' GM's Johnson said. 'We do expect modest employment growth. Consumers are starting to spend, albeit cautiously.' Toyota, the world's largest automaker, sold 147,162 Toyota, Lexus and Scion vehicles in September, 17 percent more than a year ago, the company said in an e-mailed statement. The automaker's deliveries were expected to gain 21 percent, the average estimate of four analysts. Honda, the second-largest Japanese carmaker, sold 97,361 Honda and Acura vehicles last month, up 26 percent from a year ago, the company said in an e-mailed statement. The average of four analysts' estimates was for 32 percent increase. Nissan, Japan's third-largest automaker, sold 74,205 Nissan and Infiniti vehicles last month, up 34 percent from a year earlier, Al Castignetti, vice president of U.S. sales, said in an interview. Car deliveries expanded 36 percent, led by a 65 percent jump for Altima sedans, he said. 'This year has been a bit of a rollercoaster ride,' Castignetti said. Sales should keep improving for the rest of 2010, particularly as light-truck demand remains strong, he said. Nissan was expected to boost sales 30 percent, the average estimate of four analysts. Hyundai Motor Co., South Korea's largest automaker, boosted sales 48 percent to 46,556 last month, led by increased deliveries of Sonata sedans and Tucson sport-utility vehicle. Retail sales to individual drivers, excluding those to rental companies and business fleets, surged 73 percent, Hyundai's U.S. unit said. _ With assistance from Alan Ohnsman in Los Angeles, Craig Trudell in Southfield, Mich., and Courtney Schlisserman in Washington. 