Robust little rover.
Well, the fact it's just sitting there doing nothing is probably helping its longevity
Chang'e 3 and Yutu are now the longest-lived lunar spacecraft ever by a considerable margin, right?
Actually, the fact that the little jade rabbit can't position itself to the best attitude for solar heating/radiative cooling and can't close its thermal cover to protect the electronics boxes from the extreme cold of the lunar night means that just sitting there makes it even harder for it to survive this long.
But yes, not counting the ALSEP packages (which weren't spacecraft, but you could make the case that Yutu is a rover, not a spacecraft), the Chang'e 3/Yutu combo are the most long-lived equipment deployed on the Moon. It makes me weep at how many new vistas it might have shared with us if Yutu had been able to rover freely all this time.