Detroit - US magazine Consumer Reports said on Tuesday that it was reversing a practice of recommending all new Toyota cars and trucks after two models earned below-average rankings in a closely watched reliability study.
The step marked the latest setback for Toyota after a period of fast growth in the United States that has made it the No. 2 player in the world's largest car market.
In recent years, Japanese car brands, led by Toyota, have dominated Consumer Reports' influential study of the most reliable new vehicles.
Besides its influence with car shoppers, the annual study is used by major carmakers as a proxy for their performance in improving and maintaining vehicle quality.
Although Toyota ranked third in reliability behind only Honda and Subaru, Consumer Reports also found two Toyota models had "below average" predicted reliability.
Those two models were the V6 version of Toyota's flagship Camry sedan and the four-wheel-drive, V8 version of its new Tundra pickup truck.
"Consumer Reports will no longer recommend any new or redesigned Toyota-built models without reliability data on a specific design," the publication said in a statement. "Previously, new and redesigned models were recommended because of the automaker's excellent track record."
The same study found gains for Ford, which landed three models on the magazine's "most reliable" list.
Consumer Reports ranked the Ford Fusion, Mercury Milan and the automaker's market-leading F-150 pickup truck with a V-6 engine as among the most-reliable new vehicles on the market.
"Ford continues to improve," David Champion, director of auto testing for Consumer Reports, said in a statement. "We believe Toyota is aware of its issues and trying to fix problems quickly."
Champion was due to brief reporters in Detroit on the results of the annual survey on Tuesday.
Representatives for Toyota and Ford were not immediately available for comment.
In the first nine months of this year, Toyota had a 16.2% share of the US market for new cars and light trucks, behind only General Motors at 23.8%.
But the Japanese carmaker's fast growth since 2000, when it had less than 10% of the US market, has left it facing new pressure and scrutiny.
Toyota, which has won credit with consumers for its reputation for quality and fuel-efficiency, has also come under fire from environmental groups.
Although Toyota dominates the market for fuel-efficient hybrids with its Prius, it has joined Detroit-based carmakers in lobbying against stringent increases in fleetwide fuel economy.
Consumer Reports is published by the nonprofit Consumers Union. The magazine accepts no paid advertising.
The publication's "predicted reliability" study for new model vehicles is based on an average of consumer ratings of the same model in the recent years.
The magazine surveys readers and visitors to its website about their experience with the cars and trucks they own.
Here are the magazine's "Two Best" and "Worst Picks" for predicted reliability in aach segment:
Best: Toyota Yaris, Honda Fit
Worst: Dodge Caliber, Volkswagen Jetta
Best: Toyota Prius, Honda Accord
Worst: Chevrolet Impala, Volkswagen Passat
Best: Lexus GS450h (hybrid), Acura TSX
Worst: Cadillac STS, Mercedes-Benz CLS
Best: Pontiac Vibe, Scion xB
Worst: Chevrolet Uplander, Hyundai Entourage
Best: Honda Element, Mitsubishi Outlander
Worst: Dodge Nitro, Jeep Wrangler (four-door)
Best: Toyota Highlander, Honda Pilot
Worst: Land Rover Range Rover, Land Rover Range Rover Sport
Best: Toyota Land Cruiser (no second pick)
Worst: Chevrolet Suburban 2500, GMC Yukon XL 2500
Best: Toyota Tundra (V8, two-wheel-drive), Toyota Tacoma (four-cylinder)
Worst: Cadillac Escalade EXT, Toyota Tundra (V8, four-wheel-drive)