A recent episode of Sandy Munro’s Tesla Model Y teardown series has revealed that the electric car company utilized friction stir welding (FSW) for the crossover’s thermal management system. The welding technique is commonly used among aerospace companies, like SpaceX, as a way to maintain the strength of aluminum parts while securing a reliable bond between pieces.
Munro’s analysis of the Octovalve coolant system revealed Tesla’s techniques for the revised thermal management portion of the Model Y. Munro discovered the Octovalve on April 4 after digging into the Model Y’s internal build. The new coolant assembly seemed to be a revised version of the Model 3’s “Superbottle,” which served as the heart of the sedan’s thermal management system.
A car’s thermal management apparatus is responsible for controlling and maintaining proper temperatures in critical portions of the vehicle. In the case of the Model Y, the Octovalve is responsible for motor, battery, and cabin cooling, according to Munro. The Detroit auto veteran said that typically, these systems should not be cooling the cabin if they are controlling battery or motor temperature. The thermal management system in the Model Y seems to be controlling the cabin, the battery, the electronics, and the motor nonetheless.
The Octovalve seems to be a state-of-the-art system as it uses, “some clever little ball valves that open and close to make sure that everything’s getting heated or everything’s being cooled to where it needs to be,” Munro said.
With the assembly overlooking the temperature for these many parts of the vehicle, the system is subjected to drastic and sharp temperature changes. Over time, the difference between heat and cold can begin to weaken portions of the car part, especially if it was exposed to excessive temperatures during manufacturing. This is where some SpaceX-grade solutions come into play.
Tesla chose to utilize friction stir welding for its aluminum portions of the coolant assembly. “This is a cool way of putting two parts of aluminum together, some other materials as well, but aluminum is kind of the most suited for it. And in essence, what happens is you have a stylus that spins around very very quickly. It pokes through the two pieces of metal that you want to friction stir weld. Then, it goes around the outside edge, and what it does is it uses the plastic state or thixotropic state of the aluminum to bind it together,” Munro said.
Simply put, the process allows aluminum to reach a temperature that allows two pieces of metal to come together with a strong bond, but it never turns the metal into a soft, liquid-like state. “It’s like soft butter, butter that you could see is firm, but you could cut it with a knife.”
The advantage of using this process is that the heat from the welding process only applies to the outer edges of the metal. The additional material that is not bonded to anything does not see the heat and is not weakened by the welding process. Stir welding is also time effective as it can be completed in a short period, but it is a careful process that does not apply unneeded stress upon the rest of the assembly.
SpaceX uses friction stir welding for its rockets, as it increases strength by exposing only the bonded portions of two pieces of metal to each other. Friction stir welding was used by SpaceX back in 2008 when the company was combining barrel sections of the Falcon 9’s second stage. “The FSW joins metal without flames, sparking, inert gasses, or fumes, and produces a far superior weld in aluminum-lithium alloys as compared to traditional methods,” SpaceX said in a news update.
In the spirit of humor, Tesla and Elon Musk saw the Octovalve as a perfect opportunity to not only improve the performance of the vehicle temperature regulation system but also as an appropriate time to sprinkle in some additional humor in the form of an Easter Egg. The Model 3 donned a cape-wearing bottle-figured superhero for its “Superbottle” system, while the Model Y includes a snowflake-stamped Octopus as an Easter Egg.
Tesla has increased the effectiveness of its thermal management with the introduction of the Model Y’s Octovalve system. Elon Musk stated that it was some of the best engineering he had ever seen. The welding process could increase the longevity of the machine through its lack of exposure to excessive heat and stress during manufacturing.
Watch Munro’s video on the Model Y’s Octovalve welding below.
Tesla has officially launched public Robotaxi rides in Austin, Texas, without a Safety Monitor in the vehicle, marking the first time the company has removed anyone from the vehicle other than the rider.
The Safety Monitor has been present in Tesla Robotaxis in Austin since its launch last June, maintaining safety for passengers and other vehicles, and was placed in the passenger’s seat.
Tesla planned to remove the Safety Monitor at the end of 2025, but it was not quite ready to do so. Now, in January, riders are officially reporting that they are able to hail a ride from a Model Y Robotaxi without anyone in the vehicle:
I am in a robotaxi without safety monitor pic.twitter.com/fzHu385oIb
— TSLA99T (@Tsla99T) January 22, 2026
Tesla started testing this internally late last year and had several employees show that they were riding in the vehicle without anyone else there to intervene in case of an emergency.
Tesla has now expanded that program to the public. It is not active in the entire fleet, but there are a “few unsupervised vehicles mixed in with the broader robotaxi fleet with safety monitors,” Ashok Elluswamy said:
Robotaxi rides without any safety monitors are now publicly available in Austin.
Starting with a few unsupervised vehicles mixed in with the broader robotaxi fleet with safety monitors, and the ratio will increase over time. https://t.co/ShMpZjefwB
— Ashok Elluswamy (@aelluswamy) January 22, 2026
Tesla Robotaxi goes driverless as Musk confirms Safety Monitor removal testing
The Robotaxi program also operates in the California Bay Area, where the fleet is much larger, but Safety Monitors are placed in the driver’s seat and utilize Full Self-Driving, so it is essentially the same as an Uber driver using a Tesla with FSD.
In Austin, the removal of Safety Monitors marks a substantial achievement for Tesla moving forward. Now that it has enough confidence to remove Safety Monitors from Robotaxis altogether, there are nearly unlimited options for the company in terms of expansion.
While it is hoping to launch the ride-hailing service in more cities across the U.S. this year, this is a much larger development than expansion, at least for now, as it is the first time it is performing driverless rides in Robotaxi anywhere in the world for the public to enjoy.
Tesla has scheduled its Earnings Call for Q4 and Full Year 2025 for next Wednesday, January 28, at 5:30 p.m. EST, and investors are already preparing to get some answers from executives regarding a wide variety of topics.
The company accepts several questions from retail investors through the platform Say, which then allows shareholders to vote on the best questions.
Tesla does not answer anything regarding future product releases, but they are willing to shed light on current timelines, progress of certain projects, and other plans.
There are five questions that range over a variety of topics, including SpaceX, Full Self-Driving, Robotaxi, and Optimus, which are currently in the lead to be asked and potentially answered by Elon Musk and other Tesla executives:
- You once said: Loyalty deserves loyalty. Will long-term Tesla shareholders still be prioritized if SpaceX does an IPO?
- Our Take – With a lot of speculation regarding an incoming SpaceX IPO, Tesla investors, especially long-term ones, should be able to benefit from an early opportunity to purchase shares. This has been discussed endlessly over the past year, and we must be getting close to it.
- When is FSD going to be 100% unsupervised?
- Our Take – Musk said today that this is essentially a solved problem, and it could be available in the U.S. by the end of this year.
- What is the current bottleneck to increase Robotaxi deployment & personal use unsupervised FSD? The safety/performance of the most recent models or people to monitor robots, robotaxis, in-car, or remotely? Or something else?
- Our Take – The bottleneck seems to be based on data, which Musk said Tesla needs 10 billion miles of data to achieve unsupervised FSD. Once that happens, regulatory issues will be what hold things up from moving forward.
- Regarding Optimus, could you share the current number of units deployed in Tesla factories and actively performing production tasks? What specific roles or operations are they handling, and how has their integration impacted factory efficiency or output?
- Our Take – Optimus is going to have a larger role in factories moving forward, and later this year, they will have larger responsibilities.
- Can you please tie purchased FSD to our owner accounts vs. locked to the car? This will help us enjoy it in any Tesla we drive/buy and reward us for hanging in so long, some of us since 2017.
- Our Take – This is a good one and should get us some additional information on the FSD transfer plans and Subscription-only model that Tesla will adopt soon.
Tesla will have its Earnings Call on Wednesday, January 28.
Elon Musk shared an incredible detail about Tesla Cybercab’s potential efficiency, as the company has hinted in the past that it could be one of the most affordable vehicles to operate from a per-mile basis.
ARK Invest released a report recently that shed some light on the potential incremental cost per mile of various Robotaxis that will be available on the market in the coming years.
The Cybercab, which is detailed for the year 2030, has an exceptionally low cost of operation, which is something Tesla revealed when it unveiled the vehicle a year and a half ago at the “We, Robot” event in Los Angeles.
Musk said on numerous occasions that Tesla plans to hit the $0.20 cents per mile mark with the Cybercab, describing a “clear path” to achieving that figure and emphasizing it is the “full considered” cost, which would include energy, maintenance, cleaning, depreciation, and insurance.
Probably true
— Elon Musk (@elonmusk) January 22, 2026
ARK’s report showed that the Cybercab would be roughly half the cost of the Waymo 6th Gen Robotaxi in 2030, as that would come in at around $0.40 per mile all in. Cybercab, at scale, would be at $0.20.
Credit: ARK Invest
This would be a dramatic decrease in the cost of operation for Tesla, and the savings would then be passed on to customers who choose to utilize the ride-sharing service for their own transportation needs.
The U.S. average cost of new vehicle ownership is about $0.77 per mile, according to AAA. Meanwhile, Uber and Lyft rideshares often cost between $1 and $4 per mile, while Waymo can cost between $0.60 and $1 or more per mile, according to some estimates.
Tesla’s engineering has been the true driver of these cost efficiencies, and its focus on creating a vehicle that is as cost-effective to operate as possible is truly going to pay off as the vehicle begins to scale. Tesla wants to get the Cybercab to about 5.5-6 miles per kWh, which has been discussed with prototypes.
Additionally, fewer parts due to the umboxed manufacturing process, a lower initial cost, and eliminating the need to pay humans for their labor would also contribute to a cheaper operational cost overall. While aspirational, all of the ingredients for this to be a real goal are there.
It may take some time as Tesla needs to hammer the manufacturing processes, and Musk has said there will be growing pains early. This week, he said regarding the early production efforts:
“…initial production is always very slow and follows an S-curve. The speed of production ramp is inversely proportionate to how many new parts and steps there are. For Cybercab and Optimus, almost everything is new, so the early production rate will be agonizingly slow, but eventually end up being insanely fast.”
BREAKING: Tesla launches public Robotaxi rides in Austin with no Safety Monitor
Tesla Earnings Call: Top 5 questions investors are asking
