AUSTIN, Texas — Tesla has started pushing its newest Full Self-Driving software to some of the oldest cars in its fleet, distilling the intelligence of its latest neural networks onto the aging HW3 computer with a release it calls FSD v14.3 Lite.
The rollout arrived over the weekend as part of software update 2026.38.5.11, which Tesla began sending out on Saturday, October 24. HW4/AI4 vehicles received FSD v14.3.13, while owners of 2020-and-older Model S and Model X cars running the older HW3 computer began reporting the new Lite build within days. Tracking services TeslaFi and Tessie showed the update on roughly 10% of the fleet by Monday, and the quick uptake reflects how central the software has become for owners — a trend underscored when FSD's attach rate climbed past 75% in North America last quarter.
FSD v14 Comes to Older Hardware
For years, HW3 owners wondered whether their cars would be left behind as Tesla's self-driving stack grew more demanding. The Lite build answers that directly. Tesla says it distilled the HW4 version 14 intelligence down to fit HW3, carrying over marquee advances such as reinforcement learning and the company's new offline models. Early drivers describe noticeably smoother behavior: quicker merges, better reads on pedestrians and traffic lights, fewer false slowdowns, and more consistent lane centering.
The Lite release also adds practical polish. New parking, unparking and reversing routines join a set of Arrival options that let the car finish in a parking lot, at the street, in a driveway or at the curb. A new, extra-gentle "SLOTH" speed profile sits below the familiar CHILL mode, and Tesla has made Speed Profiles available at all times. The improvements build on Tesla's broader push to make its software smarter, including its decision to build its own AI maps to sharpen FSD navigation.
