The most (and least) reliable cars

Find out after the jump…

While Honda and Toyota still dominate in reliability, General Motors has improved considerably in our latest predicted-reliability Ratings. Those are the findings of our 2010 Annual Auto Survey, based on subscribers’ experiences with 1.3 million vehicles.

While some GM nameplates had been among the least reliable brands in past years, they now rank above some major European competitors. But as a company, GM is still far from tops in reliability.

Across GM brands (Buick, Cadillac, Chevrolet, and GMC), 69 percent of models had average or better reliability. Cadillac improved the most, rising seven places from last year’s ranking. Chevrolet had its best showing in years; 83 percent of models had average or better scores in predicted reliability, up from 50 percent. Also noteworthy:

The major Asian brands are still doing well overall. All models from Acura, Honda, Hyundai, Infiniti, Scion, and Toyota have at least average predicted reliability.

Ford continues to be the most reliable American automaker. Ninety percent of Fords, including Lincoln models, have at least average reliability.

Chrysler remains the lowest-ranked manufacturer in our survey. We can recommend only one of its vehicles, the four wheel-drive Dodge Ram 1500.

While European reliability had been improving, momentum seems to have stalled. All Porsche and Volvo models are rated average or better. But Audi, BMW, and Mercedes-Benz are among the worst automakers overall.

The Porsche Boxster has the best predicted reliability in our survey, while the Audi A6 3.0T and Jaguar XF have the worst.

Detroit’s gains

General Motors and Ford have taken different paths to improving reliability. GM discontinued many of its below-average models, and some redesigns have scored well. Ford has been fine-tuning some older platforms, which gets around the bugs that often plague a new vehicle or major redesign.

Recent GM introductions, such as the Buick LaCrosse V6 (FWD), Cadillac SRX, and Chevrolet Camaro and Equinox, are proving reliable from the get-go. And some older models, such as the Chevrolet Avalanche, Corvette, and Suburban, have improved to average. Last year, all Cadillac models were below average. This year, about half its models rated at least average.

Ford’s quality renaissance has been led by the midsized Fusion, which has been very reliable since its debut five years ago. Some new models from Ford have struggled out of the gate, but the hightrim Flex EcoBoost and Lincoln MKT sportutility vehicles rated above average in their first year.

Chrysler, Dodge, and Jeep are saddled with dated vehicles that rate below average in reliability. But since Chrysler’s acquisition by Fiat, many of its products will either be replaced or redesigned.

Asia still dominates

Despite recent safety recalls, Toyota models, including those from Scion and Lexus, remained among the most reliable and earned top scores in five vehicle categories. Only the all-wheel-drive Lexus GS and the new Lexus IS 250 convertible are below average. The redesigned 2010 Toyota Prius, hurt by antilock brake problems on early vehicles, scored only average. That is quite a drop from previous years. (We’ve reinstated our recommendations for eight Toyota models that had problems with sticking accelerator pedals.)

Honda and Acura are among the top four brands, with their models topping five vehicle categories. But problems with rear brake pads help drop the 4-cylinder Accord and Acura TSX to average.

Hyundai and Kia continued to do well, with only one model, the Kia Sedona minivan, rated below average. All six new models for 2010 had average or better reliability, an impressive first-year showing.

Nissan’s mainstream models did fine. But the small Nissan Cube had a below average score in its first appearance in our survey. The Infiniti models were all average or better.

Subaru had a good record overall, with a top rating going to the four-cylinder Legacy sedan and the non-turbo version of the Forester SUV. The WRX was the only model that rated below average.

Europe’s bumpy road

BMW had a bad year, with five of 11 models now scoring below average. Although the BMW M3 topped the sporty cars category, the 1, 3, and 5 Series models with the 3.0-liter, turbocharged engine had high problem rates related to the fuel system, among other issues.

Mercedes-Benz had the least reliable vehicles in three categories. Six of its 13 models were below average, and the GLK SUV was far below average this year. The redesigned E350 sedan was above average, but the new E-Class coupe, a wholly different car, was a disappointment.

Almost three-quarters of the Audi models we analyzed were below average. Volkswagen did better, with its Golf (formerly Rabbit) doing very well and the various Jetta models doing average or better.

Our reliability survey

Our data are based on an annual survey of subscribers to Consumer Reports and ConsumerReports.org and are not derived from road tests. A model needs at least 100 responses per model year for us to score it.

From the survey, we create a reliability history for each model over the course of 10 years, 2001 to 2010. We use the data, in part, to forecast how well the 2011 models will hold up. We might predict reliability for a newly redesigned model, but only if previous versions had outstanding reliability.

Detailed Reliability data pinpoints problems

Each of the 17 problem areas we survey covers a host of possible faults. For instance, “Power Equipment” includes keyless entry, dashboard warning lights, tire-pressure monitor, and other things. “Body integrity” includes squeaks and rattles, seals and weather stripping, and air or water leaks, among other things. “Major Engine” problems include cylinder head and timing belt besides replacing the engine itself, while “Minor Engine” includes oil leaks, accessory belts and engine mounts.

To access the finer level of detail, choose any car, new or used, and go to its model-overview page. Click on the tab labeled “Reliability” and that will call up the reliability history, a grid of our familiar red and black scoring icons covering 17 trouble areas and however many model years we have data for.

Some of those individual colored “blobs” are flagged with a gold corner triangle with a “+” sign that indicate when more specific details are available. Click on that triangular corner tab to see more information on the problems owners have experienced.

As an example, looking at the Ford F-150 pickup, we can see multiple years of brake problems. However, in some years the problems were mainly attributed to pulsation or vibration, while in other years it was premature wear. Further, we note that the 2008 model had climate system problems. Now subscribers can see that the major gripe was the automatic climate system control rather than, say, a problem with the air conditioner itself.

Not all trouble spots are flagged. That’s because either no or very few specific problems were reported, or because nothing stood out enough in the sub-categories to warrant special mention.

-Consumers Union of U.S., Inc