Tesla CEO and founder Elon Musk just announced via Twitter and the company blog that the drivetrain warranty for the 85 kWh Model S has been extended, giving it an eight-year, infinite-mile warranty to match that of the battery pack. This new warranty arrangement applies retroactively to every Model S ever produced, too, meaning it benefits both existing and new owners.

Model S drivetrain warranty increased to infinite miles, applies retroactively … teslamotors.com/blog/infinite-…
Elon Musk (@elonmusk) August 15, 2014

Originally, the Model S carried a four-year, 50,000-mile limited warranty that could be extended to 8 years and 100,000 miles for an additional $4,000 fee. Musk says in his blog post detailing the move that “[i]n hindsight, this should have been [Tesla’s] policy from the beginning of the Model S program,” as the company’s warranty should reflect its belief in the improved reliability of its electric engines vs. their gasoline-powered equivalents.

Musk also notes to investors in his company that this will have a (moderate) negative effect on its earnings in the short-term, but says the move is designed to benefit the company long-term, owing to how it reflects Tesla putting its customers first.

The warranty extends to new owners upon resale of the Tesla S, too, so secondary markets also benefit. This is a huge goodwill gesture for Elon to make for its customers, and yet another shot across the bow of traditional fuel-injected gas engines. The fact that it applies retroactively makes it much more than a gesture, too, as they likely could’ve easily applied it going forward and still received praise from industry observers.