American carmakers, especially General Motors and Ford, complain that their cars are often as reliable as anything from Japan, and the real problem is simply that consumers don't believe them. Too many people assume these are still the companies that gave us rotten-to-the-core rust-buckets like the Ford Pinto in the '70s and the Chevrolet Citation of the '80s.

But the ongoing improvement of Ford and GM was one highlight of the J.D. Power and Associates 2010 Vehicle Dependability Study, one of the industry's most closely watched measures of car quality. This year's biggest surprise: For the first time in a decade, the industry's single most reliable car was from Detroit: The Cadillac DTS luxury sedan. In fact, seven of the 10 most-reliable vehicles in the study were built by Ford or General Motors.

The VDS measures problems in three-year-old cars, so it delivers a loud and clear picture of what owners really think after their cars have logged some serious mileage. This year's study surveyed more than 52,000 owners of model-year 2007 vehicles, who checked off 198 different problem areas that cover every aspect of a vehicle. Important to note is that survey-takers are not simply asked about what breaks, but also things that simply bug them about their cars, from a loud cabin to poor ergonomics.

Do you agree with the results of the J.D. Power Dependability Study?

The Cadillac DTS sedan, with just 76 reported problems for every 100 vehicles, led every car in the field. That compares with the industry average of 155 problems-per-100 vehicles. The industry overall posted a 7 percent gain in bumper-to-bumper dependability in the study, cutting the average number of problems per 100 vehicles from 167 last year to 155 — the fewest ever reported in the study.

Compare: Cadillac DTS vs. Lincoln MKS

As always, the study revealed both good and bad news for brands, with some leapfrogging several spots and others now bringing up the rear (a position that always leaves executives with plenty of explaining to do). Porsche was the single most dependable brand, jumping from 11th place last year, with just 110 problems per 100 vehicles. (Porsche also topped Power's Initial Quality Study that measures problems after 90 days of ownership.) Lincoln took second place, jumping six spots in this year's rankings. Ford's luxury brand was followed, in order, by Buick, Lexus, Mercury, Toyota and Honda. Among individual models, the Cadillac CTS, Buick LaCrosse, Buick Lucerne, Ford Five Hundred, Lincoln MKZ, Mercury Milan and Mercury Montego all scored Top 10 finishes.

Compare: Honda Fit vs. Subaru Impreza

Analysts said the results also show that some brands don't get proper credit from consumers for just how reliable their cars actually are. Cadillac, Hyundai, Ford, Lincoln and Mercury are all brands that score well in long-term reliability, although they don't always get such recognition from customers.

"Producing vehicles with world-class quality is just part of the battle for automakers; convincing consumers to believe in their quality is equally as important," said David Sargent, vice president of global vehicle research at J.D. Power and Associates. "It takes considerable time to positively change consumer perceptions of quality and dependability — sometimes a decade or more."

The study should also remind people that Toyota's cars, despite its recent high-profile recalls, are still among the most reliable. Toyota took four segment awards, more than any other brand, with the Prius hybrid, Highlander crossover, Sequoia SUV and Tundra pickup ranked the most dependable in their respective classes.

Compare: Buick LaCrosse vs. Toyota Camry

All three Ford brands — Ford, Lincoln and Mercury — beat the industry average. But the news wasn't all good for Detroit. At GM, only Cadillac and Buick topped the industry average; its Saturn, GMC, Hummer, Chevrolet and Saab brands still fell below average, though some markedly improved their scores. (Saturn and Hummer, of course, no longer need to worry what studies like this one mean for their reputation.) And some things never change: Not one Chrysler brand scored better-than-average in dependability, with Chrysler, Dodge and Jeep actually dropping in the brand rankings this year, including a lowly 33rd place finish for Jeep.

While Land Rovers may be sturdy off-road, they continue to occupy the notorious last place on the dependability chart, finishing 36th among all brands, below the other perennially poor performers such as Suzuki, Volkswagen, Jeep and MINI.

Top Models Per Segment
Sub-Compact Car
Honda Fit
Compact Premium Sporty Car
Compact Car
Toyota Prius
Entry Premium Vehicle
Lincoln MKZ
Compact Sporty Car
Mazda MX-5 Miata
Midsize Premium Car
Audi A6
Midsize Sporty Car
Chevrolet Monte Carlo
Large Premium Car
Cadillac DTS
Midsize Car
Buick LaCrosse
Premium Sporty Car
Mercedes-Benz SL-Class
Large Car
Mercury Montego
Compact Multi-Activity Vehicle
Honda CR-V
Midsize Pickup
Honda Ridgeline
Midsize Multi-Activity Vehicle
Toyota Highlander
Midsize Van
Ford Freestar
Large Multi-Activity Vehicle
Toyota Sequoia
Midsize Premium Multi-Activity Vehicle
Lexus GX 470
Large Pickup
Toyota Tundra
Large Premium Multi-Activity Vehicle
Lincoln Mark LT
Top 10 Nameplates (by PP100)
1. Porsche110
2. Lincoln114
3. Buick115
4. Lexus115
5. Mercury121
6. Toyota128
7. Honda132
8. Ford141
9. Mercedes-Benz142
10. Acura143

A Michigan native forged and raised in Detroit and a former auto critic at the Detroit Free Press, Lawrence Ulrich now lives in Brooklyn, New York. His reviews and features appear regularly in The New York Times, Robb Report, Popular Science and Travel + Leisure Golf.

For commentary on the latest auto industry trends or in-depth analysis of developments affecting consumers, turn to MSN Autos' Industry Insider for the real story behind the facts and figures. Written by respected veterans in the field, Industry Insider delivers expertise and insight that helps make sense of the automotive world.

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