Tesla has launched FSD V12.5.5 with update 2024.32.20, which has just hit early access testers. This update includes several new things, including the new end-to-end highway stack and bringing FSD to the Cybertruck for the first time. Tesla also outlined additional features to expect in future revisions of FSD.
The End-to-End part of the stack means that rather than hand-coding all the decision-making directly into FSD, Tesla now relies upon AI, trained upon hundreds of thousands of hours of footage gathered by its fleet, to make decisions.
This is key to rapid improvements and will help to bring Unsupervised FSD – and Robotaxi – to realization. We’re especially excited to see these improvements with the Robotaxi event just around the corner.
End-to-End Highway Stack
FSD V12 brought the End-to-End stack to City Streets, and the Highway Stack was still running FSD V11. With this update, end-to-end AI will now be used on the highway, which should be a considerable improvement.
When End-to-End was introduced on city streets, it brought some drastic improvements in how FSD was handled between V11.4.9 and V12.3.6. There’s likely going to be a similar level of improvement between FSD V12.5.4 on the highway and FSD V12.5.5 on the highway.
As of today, FSD still tends to sit in the left lane, Auto-Speed doesn’t function on the highway, and the speed limit can change drastically where it's incorrectly mapped.
With the end-to-end highway stack, we could see FSD correctly use the left lane to overtake vehicles and then come back into the middle or right lane, as required. In addition, we could see Tesla add Auto-Speed functionality for the highway so that the vehicle is able to more fluidly respond to changes in traffic and speed more naturally.
Upcoming Improvements
In the release notes for FSD 12.5.5, Tesla also updated the list of features coming in future FSD versions, some of which Tesla hadn’t previously discussed or mentioned in the FSD Roadmap. In Tesla’s release notes, they specifically mention these upcoming improvements:
Earlier and more natural lane change decisions
Improved performanec in parking lots
Improved performance at intersections and stops
Introduction of Speed Profile
Earlier and More Natural Lane Changes
First off, Tesla mentions earlier and more natural lane change decisions. We’ve seen this one pop up before, and it's definitely a pain point for Tesla. Even today on FSD V12.5.4, FSD will still sometimes make lane change decisions within less than 200 feet of a turn, moving you from the far right to the left turning lane in a short space.
Addressing this will greatly help how smooth FSD will feel.
Improved Performance in Parking Lots
Tesla also mentions improved parking lot performance as coming soon. This particular enhancement to FSD will likely help improve Actually Smart Summon so that it can expand beyond FSD-specific updates and become available to more users. This will allow users with Enhanced Autopilot and owners outside of North America to gain access to Actually Smart Summon for the first time. Currently, Actually Smart Summon is available to users in North America with 2024.27.25.
In addition, we’re expecting Banish – also known as Reverse Summon – to rely upon these improvements. Banish will allow your vehicle to drop you off at an entrance to a location, and then find a parking stall, and park itself. This is going to be another key item for Robotaxi and Unsupervised FSD and is one of the items we’re the most excited about.
Improved Performance at Intersections and Stops
FSD V12.5 brought along some oddities regarding intersections. Owners have been reporting FSD stopping for green lights or double braking on stop signs. This feature is likely to target some of these existing issues.
While FSD V12.5 also brought pretty drastic improvements for roundabouts, there are still some issues with signalling and lane selection in multi-lane roundabouts, so maybe they’ll address those here as well. This is a pretty broad category, so we can only imagine what they’ll be doing here.
Introduction of Speed Profile
We previously reported that Elon Musk wanted to add a new FSD drive mode. It appears that FSD’s Assertive Mode will become “Hurry Mode.” However, based on the release notes, Tesla seems to imply that it may not be called Hurry Mode but instead Speed Mode. This mode will likely be an option that tells FSD to go a bit faster and also become more aggressive with overtaking – something that has become more common and much smoother with FSD V12.5. This is going to be an interesting addition or change, and we’ll be sure to dig into it more in the future when it becomes available.
Release Date
Tesla’s Autopilot director Ashok Elluswamy posted on X that while the Cybertruck is receiving FSD 12.5.5 with the end-to-end highway stack, don’t expect it to roll out to other vehicles immediately. Tesla prioritized getting this out for the Cybertruck and they’re still working on getting the highway stack ready for other vehicles. Ashok said that he expects Tesla to have an internal build ready in about a week or so. With Tesla’s robotaxi event just 10 days out, it sounds like this won’t arrive on customer vehicles until after the event.
Great job by the @Tesla_AI team on meeting the goals laid out for September🤩
End-to-end on the highway is first shipping to Cybertrucks. We are close to an early release build for remaining platforms and will release to internal employees in the next week or so.
Tesla has pioneered the use of single-piece castings for the front and rear sections of their vehicles, thanks to its innovative Gigapress process. Many automakers are now following suit, as this approach allows the crash structure to be integrated directly into the casting.
This makes the castings not only safer but also easier to manufacture in a single step, reducing costs and improving repairability. For example, replacing the entire rear frame of a Cybertruck is estimated to cost under $10,000 USD, with most of the expense coming from labor, according to estimates shared on X after high-speed rear collisions.
These insights come from Sandy Munro’s interview (posted below) with Lars Moravy, Tesla’s VP of Vehicle Engineering, highlighting how these advancements contribute to the improvements in Tesla’s latest vehicles, including the New Model Y.
However, with the new Model Y, Tesla has decided to go a different route and eliminated the front gigacast.
No Front Casting
Tesla’s factories aren’t equipped to produce both front and rear castings for the Model Y. Only Giga Texas and Giga Berlin used structural battery packs, but these were quickly phased out due to the underwhelming performance of the first-generation 4680 battery.
Tesla has gone back to building a common body across the globe, increasing part interchangeability and reducing supply chain complexity across the four factories that produce the Model Y. They’ve instead improved and reduced the number of unique parts up front to help simplify assembly and repair.
There is still potential for Tesla to switch back to using a front and rear casting - especially with their innovative unboxed assembly method. However, that will also require Tesla to begin using a structural battery pack again, which could potentially happen in the future with new battery technology.
Rear Casting Improvements
The rear casting has been completely redesigned, shedding 7 kg (15.4 lbs) and cutting machining time in half. Originally weighing around 67 kg (147 lbs), the new casting is now approximately 60 kg (132 lbs).
This 15% weight reduction improves both vehicle dynamics and range while also increasing the rear structure’s stiffness, reducing body flex during maneuvers.
Tesla leveraged its in-house fluid dynamics software to optimize the design, resulting in castings that resemble organic structures in some areas and flowing river patterns in others. Additionally, manufacturing efficiency has dramatically improved—the casting process, which originally took 180 seconds per part, has been reduced to just 75 seconds, a nearly 60% time reduction per unit.
Advancements in die-casting machines and cooling systems have allowed @Tesla to dramatically reduce cycle times and improve dimensional stability. pic.twitter.com/WB5ji67rvV
Tesla’s new casting method incorporates conformal cooling, which cools the die directly within the gigapress. Tesla has been refining the die-casting machines and collaborating with manufacturers to improve the gigapress process.
In 2023, Tesla patented a thermal control unit for the casting process. This system uses real-time temperature analysis and precise mixing of metal streams to optimize casting quality. SETI Park, which covers Tesla’s manufacturing patents on X, offers a great series for those interested in learning more.
The new system allows Tesla to control the flow of cooling liquid, precisely directing water to different parts of the die, cooling them at varying rates. This enables faster material flow and quicker cooling, improving both dimensional stability and the speed of removing the part from the press for the next stage.
With these new process improvements, Tesla now rolls out a new Model Y at Giga Berlin, Giga Texas, and Fremont every 43 seconds—an astounding achievement in auto manufacturing. Meanwhile, Giga Shanghai operates two Model Y lines, delivering a completed vehicle every 35 seconds.
Having the ability to open your trunk hands-free can be incredibly useful when your hands are full, especially in a busy parking lot.
Tesla vehicles now support opening the vehicle’s trunk or frunk completely hands-free — no foot waving required.
What is Hands-Free Frunk and Trunk?
Tesla implemented its hands-free feature by leveraging your phone’s position in relation to the vehicle. When you stand still behind your vehicle, the trunk will automagically open for you.
While this functionality isn’t available on every vehicle, it’s available on every vehicle Tesla manufactures today, including the new Model Y, the Cybertruck and other recent models.
With a compatible device and a supported vehicle, you can now open your Tesla’s trunk hands-free.
How It Works
Tesla’s hands-free feature requires the use of ultrawide-band (UWB) in the vehicle and on your phone. Apple and Samsung have supported ultra-wideband for a number of years and most flagship Android devices also support the low-energy feature.
Ultra-wideband allows another device to precisely detect its relative location. In this case, the vehicle is tracking where the driver’s phone is in relation to the vehicle. Since the vehicle is able to more precisely track the phone’s location, ultra-wideband also improves Tesla’s phone key feature.
Since the vehicle depends on your phone, you’ll need to have your phone on you in order to activate the hands-free feature. Simply stand within 2.5 to 3 feet from the front or rear of your vehicle for the frunk or trunk to open. You’ll then hear a couple of chimes. If you continue to stand still, then your frunk or trunk will open automatically.
The chimes serve as a warning that the trunk will open if you don’t move, which helps reduce accidental openings.
Hands-Free Trunk in Action
The video below shows how Tesla’s hands-free trunk feature works.
Supported Models
Since Tesla uses ultra-wideband to power the hands-free feature, only vehicles with the needed hardware are supported. The list of supported vehicles includes:
2021 Model S and later
2021 Model X and later
2024 Model 3 (Highland) and later
2026 Model Y (Juniper) and later
All Cybertrucks
Supported Phones
Your phone will also need to support UWB. Luckily, most manufacturers have included UWB in their devices for several years.
Apple: All Apple devices since the iPhone 11 have included UWB, except for the iPhone SE (2nd and 3rd generation). The iPhone 16e also has UWB.
Android: Most Android phones - especially flagship devices - already support and use UWB for other uses, but it’s not available on all phones. If you have a Google Pixel 6 or higher, Samsung Fold 2 or higher, Samsung S21+, or other recent Android phone, then your phone already supports ultra wideband.
Which Models Support Hands-Free Frunk
Unfortunately, not every supported model supports the hands-free frunk and trunk feature. The hands-free frunk feature is only supported on the Model S, Model X, and the Cybertruck. In addition, the Cyebrtruck is the only vehicle with a powered frunk, so while the Model S and Model X will unlock the frunk for you, you’ll still need to lift it and close it manually. The Cybertruck will open the frunk for you, much like the trunk on another Tesla.
Which Models Support Hands-Free Trunk
While most supported Tesla vehicles can use the hands-free trunk, it excludes the Cybertruck, which doesn’t have a powered trunk.
Enable Hands-Free Trunk / Frunk
If you plan to use your vehicle’s hands-free trunk feature, you’ll need to enable it in settings, as it’s off by default. Simply open Controls by tapping the vehicle icon in the bottom left corner, then navigate to the Locks section.
Within the Hands-Free section, you’ll find a few options, depending on your model. You’ll be able to choose whether to enable the hands-free frunk or trunk and whether you’d like to disable the feature at home.
Preventing Accidental Opening - Exclude Home
Although the hands-free feature requires you to stay still in front or behind your vehicle for a couple of seconds, it can still be triggered accidentally if you’re working around your garage. To prevent accidental opening of the frunk or trunk, Tesla allows you to disable the feature while your vehicle is parked at home.
Tesla determines your home location by the address that’s set in your vehicle. However, it also adds a buffer, meaning that your hands-free trunk feature will also not work in your driveway or at your neighbor’s home. The exclude home feature is located in the same spot as other hands-free trunk features, Controls > Locks > Hands-Free > Exclude Home.
If you have a recent Tesla that’s supported, go ahead and give the feature a try.
