New stats: Nada-odds and Lemon-odds

When buying a car, you probably wonder: what are the odds it will turn out to be a lemon? Does it have a shot at requiring no repairs at all?

Traditional sources of car reliability information have never answered these questions. They’ve only provided vague dot ratings that indicate how a car compares to the average for all cars. Even TrueDelta, which has been providing car models’ average repair frequencies, and not just dots, has not been directly answering these questions. Instead, you’ve had to infer your odds of getting a lemon from the average repair frequency.

With the latest update to TrueDelta’s Car Reliability Survey results, released today, this will no longer be necessary. This update includes two new statistics: “Nada-odds” and “Lemon-odds.” From a car model’s Nada-odds, you can learn how many cars out of a hundred required no repairs at all—nada—in the past year. And from its Lemon-odds you can learn how many out of a hundred had to go to the repair shop three or more times in the past year.

It turns out that the odds of getting a problem-free car are higher than you probably suspect, while the odds of getting a lemon are probably much lower. Many of the 2007, 2008, and 2009 models included in these results had a three-in-four chance—or better—of requiring no repairs at all, not even a minor one, in the past year.

And the Lemon-odds? With many fairly new cars your chances of a lemon are under one in a hundred, and under one-in-twenty is the norm. Only with the least reliable cars are your odds worse than one-in-ten. The horror stories are real, just a lot less common than many people think.

These new stats require more data on more cars. So this initial set of results covers only 100 models, 36 of which are only visible to members. As the number of participants grows, we’ll be able to provide these stats for more and more models.

“Nada-odds” and “Lemon-odds”

  • These are interesting and helpful stats. One of the biggest challenges, however, is determining how a car will hold up over time. I buy 2-3 year old cars (usually) and keep them for about 10 years.

    Looking at the stats for a 3 year old car is helpful, but, frankly, I’d expect any 3 year old car to have good stats – they are still under or just off warranty. So I care more about what happens as they age.

    So how would can True Delta’s research help one predict such long term reliability? There aren’t usually similar cars that old to look at. Perhaps stats on repair rates for a manufacturer based on age. In other words, how many time per year does the average 5 or 10 year old (or any other age) Honda or Ford require? Every manufacturer will have variations, certainly, but this might be a meaningful stat for predicting long term reliability.

  • Michael

    In my opinion there’s too much variation by model to base much on the manufacturer’s track record.

    A better approach would be to provide separate results for high-mileage cars. But this will only be feasible after we have a lot more participants.

    So we need all of the help we can get to get the word out.

  • In my opinion there’s too much variation by model to base much on the manufacturer’s track record.

    That’s an interesting observation. The conventional wisdom says that Honda and Toyota are good bets for the long term, other Japanese cars are close, domestics not so much. The Germans are durable, but not necessarily reliable. In other words, they keep going but little (or not so little) things will break along the way.

    I still think it would be an interesting statistic to look at, since folks tend to lump all cars from one manufacturer together. At the very least, people believe that this is a valuable statistic, some means of illustrating that it isn’t would be helpful.

  • Michael

    People believe a lot of things that aren’t true. Often it seems that if people have to choose between something that is easy for them to grasp, but false, and something that is true but requires some mental effort, most will choose the former. Consumer Reports already serves that market well.

  • I guess the question then is how do you make factual information easily accessible? Otherwise, folks are just going to keep going to CR. Figure out how to give them the actual relevant facts while they search for what they think they need or want to know.