The latest Which? study puts Honda, Mazda, Lexus, Toyota and Suzuki at the top of the table.
But at the other end of the scale, German brands are no longer living up to their dependable reputation. VW, which dropped into the lowest category last year, has been joined there by BMW and Audi, which has dropped two places in two years.
Ford shows it's possible for a manufacturer to reverse its reliability fortunes. Constantly rated by Which? as poor prior to 2001, this year it consolidates its position in the good category. The likes of Citroën, Fiat, Land Rover, Peugeot, Renault, Rover and Vauxhall show few signs of following suit.
The German brands occupy the bottom three places in the individual model breakdown table for cars up to two years old. The wooden spoon goes to the Audi TT for the second year running; around one in five has broken down in the last year. The old model Mercedes E-class is second from bottom, while the VW Polo is third.
However, for the third year running, not a single Mazda 323 in the survey broke down. Other cars that were breakdown-free are the Hyundai Getz, MG ZT/ZT-T, Toyota Corolla and the Toyota Corolla Verso.
"German cars have always been expensive, but our survey reveals a worrying drop in reliability that makes them look distinctly over-priced. Audi, BMW and VW may be the choice of more badge-conscious buyers, but owners of Japanese cars are far less likely to spend time on the hard shoulder or face hefty garage bills," says Malcolm Coles, editor of Which?.
In January 2004, the survey went to 80,000 randomly selected Which? readers. The responses provided information on 34,277 cars up to eight years old. The full results, including detailed information on 150 different models, will be published in September's Which? Car 2004/05.