http://www.edmunds.com/tesla/model-s/2013/long-term-road-tes...> If you're keeping score, our Model S is now on its third drive unit: the one that came with the car, the one that was replaced in November, and this latest one. And that wasn't the only thing that was replaced on this service visit.
This is when Edmunds replaced the drive unit twice. Look at the date, Feb 2014.
Later, in July 2014: http://www.edmunds.com/tesla/model-s/2013/long-term-road-tes...
Yet another drive unit replacement. Their Tesla S went through four drive trains (the first one came with the car, and then three replacements) in two years.
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Consumer Reports also had an issue with their long-term test.
http://www.roadandtrack.com/new-cars/car-technology/news/a27...
Consumer Reports is a survey methodology, as opposed to a single data-point like Edmunds. But the fact that reliability concerns are hitting the major, reputable, reviewers is worrisome to me.
This isn't JUST an Edmunds issue. Everyone is reporting reliability concerns. In part, its somewhat okay because Tesla the company stands behind their warranty and fixed the problems without issue. So as a consumer, you get excellent service.
On the other hand, dying in the middle of a highway and being forced to call a tow-truck is not an experience that should be common on a high-end luxury vehicle. The question is if Tesla has solved these issues in time for the Model 3 / mass market.