Tesla’s Two Defunct Flagship Models Are Getting a Big Upgrade

Tesla’s older Model S and Model X vehicles, which are no longer in production, are approaching the end of a long wait for a significant software update. According to Tesla’s Head of AI, Ashok Elluswamy, the rollout of Full Self-Driving (FSD) v14 Lite to these Hardware 3 models was scheduled to begin recently.

What Happened

During the Cybercab launch event, Elluswamy told journalist Ryan McCaffrey that the build for the Model S and Model X FSD v14 Lite update "was supposed to go out last week." This indicates that the software suite, which has already been deployed to other vehicles, is imminent for these specific flagship models.

The vehicles in question are the pre-refresh Model S and Model X units equipped with Tesla’s older Autopilot computer, known as Hardware 3 (HW3) or AI3. These cars differ from the current Model S and Model X, which ship with the newer Hardware 4. Tesla ceased installing the HW3 computer in new vehicles years ago, making these older flagships a closed generation of cars.

FSD v14 Lite is a distilled version of Tesla’s current v14 driving stack, designed to run on hardware that cannot support the full AI 4 model. The process involves compressing behaviors learned on newer computers, such as reinforcement learning and offline models, so that the older chips and cameras can utilize them. Early reports suggest the distilled network is approximately 15 percent the size of the original. The software remains a supervised Level 2 driving system, as Tesla has stated that HW3 lacks the memory and bandwidth to support unsupervised Full Self-Driving or robotaxi operations.

The first Lite build, firmware 2026.20.5.1, introduced features such as parking, unparking, and reversing capabilities, along with arrival options for various locations like driveways and curbsides. It also included speed profiles and improved handling of merges, forks, pedestrians, and traffic lights. A subsequent build, 2026.20.6.10, added a standalone Self-Driving app and the ability to start a trip from Park without brake-pedal confirmation. Elluswamy identified this later version as the one "likely going to wide release."

Why It Matters

This update is significant for owners of the older Model S and Model X because these vehicles have been the last major holdouts in the FSD v14 Lite rollout. While Model 3 and Model Y vehicles on the same HW3 platform began receiving the update in late June 2026, with wider North American expansion in July, the S and X models have yet to receive the software. The delay has been a source of frustration for owners, particularly given the feature list included in the Lite version.

The rollout demonstrates Tesla’s strategy of extending the utility of its legacy hardware through software optimization. By distilling the v14 stack for HW3, Tesla aims to provide a consistent driving experience across a broader fleet, even if the older hardware cannot support the full autonomy features available in newer models. For the market, this highlights the continuing value proposition of Tesla’s software-defined vehicles, where significant upgrades can be delivered to aging hardware.

However, the experience for current HW3 drivers has been mixed. Some users report substantial improvements over the previous v12.6 version, while others have noted issues such as indecision or phantom braking. The upcoming deployment to the Model S and X will test whether the software can land cleanly on these older flagships, which have waited the longest for the update.

The Bottom Line

Tesla’s Head of AI suggests that the FSD v14 Lite update for Hardware 3 Model S and Model X vehicles is imminent, having been delayed from a scheduled release the previous week. No official changelog or build number has been released for these specific models yet, but the software aims to bring key driving features to the older hardware platform, pending final model-specific validation.