Tesla FSD v14.3.8 Rolls Out in North America With Update 2026.26.6.5

Tesla started pushing update 2026.26.6.5 on August 26, 2026, and it's a notable one: it merges the Summer Update with a fresh build of Full Self-Driving (Supervised), version 14.3.8, for North America. The rollout is tiny so far — TeslaFi data shows just 3 cars on the update, or 0% of the fleet — so this is very much an early wave rather than a fleetwide push.

FSD v14.3.8 is listed for HW4 vehicles across the lineup: Model S, Model 3, Model X, Model Y, and Cybertruck.

What's new in FSD (Supervised) v14.3.8

The headline changes are under the hood, in how the neural network is trained and how quickly it runs:

• Upgraded the Reinforcement Learning (RL) stage of training the FSD neural network, which Tesla says improves a wide variety of driving scenarios.
• Upgraded the neural network vision encoder for better understanding in rare and low-visibility scenarios, stronger 3D geometry understanding, and expanded traffic sign understanding.
• Rewrote the AI compiler and runtime from the ground up with MLIR, resulting in 20% faster reaction time and faster model iteration.

On the driving behavior side, Tesla lists a long set of refinements:

• Mitigated unnecessary lane biasing and minor tailgating behaviors.
• Increased decisiveness of parking spot selection and maneuvering, plus improved parking location pin prediction — now shown on the map with a P icon.
• Enhanced response to emergency vehicles, school buses, right-of-way violators, and other rare vehicles.
• Improved handling of small animals, with RL training focused on harder examples and rewards added for proactive safety.
• Improved traffic light handling at complex intersections with compound lights, curved roads, and yellow light stopping, driven by hard RL examples sourced from the Tesla fleet.
• Better handling of rare or unusual objects that extend, hang, or lean into the vehicle's path.
• Improved handling of temporary system degradations — the car maintains control and recovers automatically without driver intervention, reducing unnecessary disengagements.
• Improved driver monitoring sensitivity, with better eye gaze tracking, eye wear handling, and higher accuracy in variable lighting.

Summon, stats, and carryover features

Tesla also rolled forward several changes introduced in earlier 14.3.x builds. The model is now unified between Actually Smart Summon, FSD, and Robotaxi for more capable and reliable behavior (new in v14.3.2 for non-Cybertrucks, v14.3.4 for the Cybertruck). Actually Smart Summon's max speed is up to 8 mph (13 km/h), added in v14.3.3 and not available on Cybertruck.

For the data-minded, you can now see distance traveled in FSD (Supervised) without an intervention, and the Self-Driving App shows your longest intervention-free streak. After taking over, you can select an intervention reason on the main screen to help Tesla improve the system. Self-Driving stats can also be viewed and shared from your phone under Mobile App > Self-Driving.

The Summer Update side of 2026.26.6.5

Because this build merges the Summer Update, the release notes list a pile of non-FSD features too, including Estimated Range, Preferred Routes, Automatic Navigation, Grok Commands and "Hey Grok," Traction Control Modes, Caraoke with Scoring, an updated Driving Visualization, Speed Cameras on Route, Custom Wraps, Camera Preview, Set Arrival Energy, Apple Music, Web Browser, Supercharger Search, a Welcome Animation, Rear Display features, and security improvements. NotaTeslaApp also flagged two undocumented changes: a rear spoiler visualization and improved lighting in the visualization.

What's still coming

Tesla's own "Upcoming Improvements" list in the release notes is short but interesting: expanding reasoning to all behaviors beyond destination handling, and adding pothole avoidance.

Under your supervision, Full Self-Driving (Supervised) can drive your Tesla almost anywhere. You and anyone you authorize must use additional caution and remain attentive. It does not make your vehicle autonomous. Do not become complacent.

What this means for owners

Nothing here changes the core rule: FSD (Supervised) still requires an attentive driver, and this release actually tightens driver monitoring with better gaze tracking and eyewear handling. If you've been getting nagged with sunglasses on, the accuracy improvements may work in your favor — but the system is watching more carefully, not less.

Practically speaking, more supervised driving time means your cabin setup matters. A solid phone mount keeps navigation and the Self-Driving app glanceable without dropping your eyes to your lap, and a clean windshield and camera housing help the upgraded vision encoder do its job in the low-visibility conditions Tesla specifically called out. If you road trip on FSD, it's also worth keeping charging adapters and a basic roadside kit in the frunk — longer intervention-free drives tend to turn into longer drives, period.

With only a handful of cars on 2026.26.6.5 right now, most owners will be waiting a while. Keep your car on Wi-Fi and check Software in the touchscreen if you want it the moment it lands in your queue.

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