In many countries the warranty period isn't binding - the product is entitled to repair as for as long as the 'expected lifetime' of the product.

For a luxury car like a Model S, you'd be well within that period still, especially given that they're being described as 'premature failures'.

> The safety regulator is examining the Model S suspension — the springs, joints and other components that connect a car to its wheels — for possible defects that could be causing premature failures.

Also, the last thing Tesla need at the moment is cars failing just outside the warranty period and then not repairing them - as noted, it just highlights their lack of support network and lack of general repairability at the moment.