It's been over a year since the U.S. Environmental Protection Agency (EPA) disclosed Volkswagen's use of illegal "defeat device" software in diesel cars to cheat on emissions tests.

But VW had another dirty little secret waiting to come to light.

That is its recall rate: cars from its Volkswagen and Audi brands have had the highest rate of recalls of any automaker over the past three decades.

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That's according to new-car sales and National Highway Traffic Safety Administration (NHTSA) recall data analyzed by (as reported by WardsAuto).

The analysis included recall data from January 1985 to September 2016, and looked at three metrics: how often a manufacturer produced vehicles that needed to be recalled, recall timeliness, and how often recalls stemmed from automakers' own investigations, rather than the NHTSA.

The Volkswagen Group had the highest rate of recalls, at 1,800 recalls per 1,000 vehicles sold.

2016 Porsche 911 Targa 4 GTS

2016 Porsche 911 Targa 4 GTS

(The former number exceeds the latter because, in some cases, individual models were recalled multiple times for different reasons).

However, it wasn't all bad news for the VW Group.

The company's Porsche brand actually had the lowest recall rate, at 531 cars for every 1,000 sold.

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Porsche was analyzed apart from the rest of the Volkswagen Group because the NHTSA treats it as a separate manufacturer in its data compilations.

(The VW Group took control of the Porsche brand several years ago, though  the two entities have long had intertwining ownership.)

Data for both the main Volkswagen brand and Audi were combined by the NHTSA.

2016 Volkswagen Golf

2016 Volkswagen Golf

A high rate of recalls may also be an indication that VW is more proactive in addressing potential defects, the report said.

And even the high recall rate comes with a positive spin.

Volkswagen had among the lowest rates of cars recalled for possible defects that could have caused "death, injury, crash, accident, or fire," according to the report.

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However, Tesla Motors was deemed to be the most proactive when it comes to recalls.

All Tesla recall campaigns were initiated by the automaker itself, rather than by the NHTSA.

Tesla has the advantage of being a relatively new manufacturer with a small number of cars on the road, and the ability to address many issues with over-the-air updates.

2016 Tesla Model S P90D and Boeing 737 drag race

2016 Tesla Model S P90D and Boeing 737 drag race

Because these software updates don't require owners to take their cars to service centers, Tesla has bristled at the use of the term "recall" to describe the fixes it implements.

The Silicon Valley automaker also had the fourth-lowest rate of recalls, at 936 cars per 1,000 sold.

Mercedes-Benz and Kia were sandwiched between Porsche and Tesla in second and third place, respectively.


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