Toyota Motor Corp., slowed by tight parts supplies since Japan’s record earthquake in March, said production at its North American auto plants is recovering faster than expected and will return to normal in September.

Full output of eight models, including Camry and Corolla cars, Sienna minivans and Highlander sport-utility vehicles, was restored June 6, and Tundra and Tacoma pickups and RAV4 and Lexus RX SUVs will reach that level by September, said Bob Carter, group vice president of U.S. sales. Toyota estimated in April that pre-quake production would resume in November, reported Bloomberg.

“Our inventories are at the bottom but will be improving quickly,” Carter said in a telephone interview yesterday from Torrance, California. “I’m doing back flips.”

Toyota, Japan’s largest automaker, has struggled to restock U.S. dealers in the months since the 9-magnitude quake and tsunami curbed supplies of its top-selling Camry and Prius hybrid. Inventory shortages led to a 33 percent drop in Toyota’s U.S. sales in May and are constraining deliveries this month.

The automaker’s sales may be “slightly over 100,000 units this month,” Carter said. “In July, you’ll see us come back to a more normalized share of the market.” The Toyota City, Japan- based company reported selling 140,604 vehicles in June 2010.

Toyota rose 0.3 percent to 3,205 yen as of 9:01 a.m. in Tokyo trading, in line with the gain in Japan’s benchmark Nikkei 225 Stock Average.

While restoring production is critical, Toyota has to revamp models such as the Camry that are under pressure from sedans from General Motors Co. and Hyundai Motor Co., said Alan Baum, principal of automotive consultant Baum & Associates in West Bloomfield, Michigan.

“Camry is a particular issue for them, since it carries the flag for the brand,” said Baum, who expects a new version of the top-selling U.S. car to arrive late this year. “Relative to competitors, in terms of quality a lot of consumers now see Toyota has just ‘one of the boys.’ They’ve got to find a way to address that.”

Toyota hasn’t said when the redesigned Camry, built at its Georgetown, Kentucky, plant and at affiliate Fuji Heavy Industries Ltd.’s Subaru factory in Indiana, will go on sale.

Toyota now has only a 37-day supply of vehicles, which will rise during the next few months, Carter said. The automaker will boost advertising to ensure U.S. customers know its dealers again have cars and trucks in stock, he said.

“There is a perception out there that Toyota dealers don’t have vehicles,” Carter said.

Incentives such as no-interest loans and discounted leases, now available on the Camry, will be expanded to other models as supplies increase, he said.

Supplies of the Prius are improving and the U.S. may get more than the 36,000-unit allotment expected for the June- through-August period, Carter said, without elaborating.

After September, Toyota will work to make up lost production, said Steve St. Angelo, the company’s executive vice president for North American engineering and manufacturing.

“Our team members and suppliers here and in Japan have worked tirelessly to get us back to 100 percent, overcoming many challenges,” he said in a statement. “The effort in Japan has been incredible, especially in the midst of such tragedy and devastation.”

The company has 14 auto-assembly and parts plants in the U.S., Canada and Mexico. Its U.S. sales unit is based in Torrance.