AUSTIN, Texas — Tesla has started pushing its latest Full Self-Driving build to some of the oldest cars still on the road, rolling out FSD v14.3 Lite to legacy Model S and Model X vehicles that run on Hardware 3 and Intel-based computers. The update, carried in firmware 2026.38.5.1, began reaching those pre-refresh cars this week and marks one of the clearest signs yet that Tesla intends to bring its newest driving intelligence to owners who bought in years ago.
Old Hardware, a New Brain
The release notes describe the effort in plain terms: Tesla engineers have worked to distill the intelligence of the Hardware 4 version of FSD v14 down into the tighter compute budget of HW3. The company points to sharper responsiveness in several driving scenarios, smoother comfort during routine driving, and new parking, unparking and reversing behavior. The rollout follows the 2026.38.5 update, known as FSD v14.3.12, that began reaching HW4 cars earlier in the week, part of the steady march toward a wider release that we tracked in our look at the last fixes standing between v14 and v15.
What the Intel Cars Get
For the Intel-based HW3 Model S and Model X, the headline addition is Speed Profiles, including a new SLOTH setting that drives more conservatively and selects lanes more cautiously than the familiar CHILL mode. The right scroll wheel now adjusts speed-profile settings, and the driver profile carries more weight over how the car behaves. A handful of extras, including Arrival Options, interface refinements and Start Self-Driving from Park, remain reserved for the newer AMD Ryzen-based HW3 cars, and the seasonal Halloween Mode is not part of this particular package.
