Automotive chemical manufacturer Prestone is currently developing a low-conductivity electric vehicle (EV) coolant that scientists hope can increase EV efficiency.
While ethylene glycol is used in both gas vehicles and EVs, including Teslas, Prestone has increased its research and development budget for learning about less conductive cooling fluids over the past year, as detailed in a report from Automotive News on Friday. Prestone EV Director Tom Corrigan says that that won’t be the case in the future, as the company seeks to develop its own.
“Essentially, EVs are borrowing the internal combustion engine fluid,” Corrigan said. “We are going to see a shift in that in the next one to two years.”
The company has been testing its low-conductivity EV coolants in Ford Mustang Mach-E vehicles at its tech center in Danbury, Connecticut, in recent months. While initial offerings are roughly two years away and will still include ethylene glycol bases, Corrigan also says that petroleum-based dielectric coolants could replace the chemistry in future years.
Coolant types may also be dependent on battery chemistries, with lithium-iron phosphate (LFP), solid-state, and nickel manganese cobalt batteries likely all requiring different coolant makeups. Tesla writes on its website that its cooling systems currently use a phosphate and nitrate-free ethylene glycol-based coolant.
Ethylene glycol can ionize over time when it interacts with metals, plastics, and other necessary engine materials. As the coolant gains electrons, the overall efficiency of a battery-electric vehicle (BEV) is decreased. In addition, the coolant chemistry is expected to shift because of safety, as a BEV-friendly replacement for the corrosion inhibitors used in ICE coolants.
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“Those ionize in the fluid and carry an electrical charge. If you have an issue where high-conductivity coolant contacts high-voltage electronics or the battery, it can lead to fire,” Corrigan explains. “So what we are working on is low-conductivity coolant.”
Scientists evaluate the electrical conductivity of coolants using a unit called microsiemens, which measures the conductivity per centimeter. In gas cars, experts expect to see between 3,000 and 5,000 microsiemens per centimeter, considered highly conductive, though it doesn’t negatively interact with gas vehicles in the same way it does for BEVs.
Instead, BEV makers are asking Prestone to develop a coolant with just 100 microsiemens per centimeter, while other fuel cell vehicles may require coolant conductivity levels of just 0.5 to 1.5 microsiemens, according to Corrigan.
“Every bit of increased conductivity is a loss of efficiency in the fuel cell. You’ve got to make the fluid very pure,” he notes.
Along with adding to the company’s R&D budget, Prestone added an additional five scientists and engineers in the department developing coolants for BEVs and fuel cells.
“We see where the future is going with EV coolants, and we want to be ready when the manufacturers are ready,” Corrigan says.
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Tesla has started to deploy the 2026 Summer Update to owners across its fleet, and among the biggest changes are improvements to Navigation, a new startup animation for the Model 3 and Model Y, Caraoke scoring, and new capabilities for Grok.
As the update has started making its way to some cars, we can now see a few of the features operating in real-time. We will show you what some of the new features look like in this article, along with some additional details on what changed.
Not all of the new features in the 2026 Summer Update have quite made an appearance, but some of them have, so we’ll show those here:
New Animation Screen for 3/Y
Tesla is rolling out a new startup animation for Tesla Model 3 and Model Y owners. This is present in Launch Edition and Performance Model 3 and Model Y, but other trim levels do not have anything like this.
The new animation screen on Model 3/Y with the 2026 Summer Update
Apparently color will also be customizable: pic.twitter.com/wSdwggtG3S
— TESLARATI (@Teslarati) July 27, 2026
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Owners can adjust the color associated with the startup animation to suit their preferences. It is a surprise that more automakers do not focus on this animation for their vehicles; it can be a great first impression piece and make the car immediately feel more luxurious.
Tesla has included this on more premium trims, but it is nice to see it on the Model 3 and Model Y.
Grok Improvements
Grok can now adjust more things in the car outside of the Navigation system. Now, drivers can adjust anything from climate to driving settings by simply speaking to the AI assistant in the car:
@Tesla‘s AI assistant (Grok) with its new vehicle commands in action.
Set the climate, your destination and vehicle settings all in one go! pic.twitter.com/0bBTqaAk6G
— Not a Tesla App (@NotATeslaApp) July 28, 2026
You don’t even have to push a button, either. Instead, you can just say “Hey, Grok,” if you have it enabled. That feature rolled out with the 2026 Spring Update just a few months back.
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This is a great feature, especially pertinent for the Robotaxi platform, as there will be no buttons inside the Cybercab when it eventually starts giving rides to the public. It also broadens Grok’s capabilities, which were relatively limited in terms of vehicle setting adjustments beforehand.
Tesla briefly offered one Robotaxi part in its Parts Catalog for your personal car, only to remove it just a short time after it was first noticed.
Tesla’s Robotaxi camera washer apparatus was briefly available for purchase on the company’s Online Parts Catalog. The camera washer was first noticed on Model Y Robotaxi vehicles about six months ago in Austin.
🚨 Tesla looks to have installed Camera Washers on the side repeater cameras on Robotaxis in Austin
pic.twitter.com/xemRtDtlRR— TESLARATI (@Teslarati) January 23, 2026
First noticed by Not a Tesla App, the Camera Washer entries appeared for the new “Juniper” Model Y under a category called “Halo,” which has also now disappeared. Interestingly, Halo probably is related to Tesla’s internal “Project Halo,” which was a project that aimed to retrofit customer-owned Model Ys into functional Robotaxis.
This hardware addition would likely be required for the vehicle to operate as a Robotaxi, as the Camera Washer seems to be a non-negotiable part of the vision-based system Tesla utilizes for self-driving efforts.
However, this part has since been removed and is no longer visible on the EPC.
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Now the true question lingers: Why would Tesla add this Camera Washer to the Model Y parts catalog? Is it planning to make it available for owners to utilize on their own cars for personal use, or will it become a prerequisite for Robotaxi operation in customer-owned cars?
While discussing the upgrade options for Hardware 3 vehicles during the Q1 Earnings Call, Tesla CEO Elon Musk had said that the company could establish small, satellite shops that would upgrade cameras and self-driving computers. Perhaps this same strategy could be utilized for vehicles that want to be included in Robotaxi but do not have the correct hardware.
AI4 is currently represented as capable of unsupervised self-driving, and the same was said about HW3 at one point, only for Tesla to admit last quarter that it would, unfortunately, not be possible. Perhaps AI4 vehicles might need this camera washer as a prerequisite, just as HW3 cars will need that camera and computer upgrade.
This could be the first hint of that’s where we are headed.
Tesla has started rolling out a broader change to the ride experience for its Robotaxi fleet by silencing turn signals, but the change is certainly polarizing.
Tesla has generally made it clear that its purpose-built ride-hailing platform, Robotaxi, will cater to the rider in nearly every way possible. This includes having climate preferences, music, and other personal settings loaded up in the car as the rider enters.
But Tesla is taking it a step further by muting turn signal chimes altogether, a change that appears to be a way to make the ride more peaceful:
Tesla has finally turned off the blinker/turn signal noises in their Model Y Robotaxis.
This is a small update, but will definitely be noticeable for riders. It didn’t really make much sense to leave the turn signal sound on when it’s Unsupervised. pic.twitter.com/ITwx60PAMO
— Sawyer Merritt (@SawyerMerritt) July 27, 2026
However, there are a handful of people who are not thrilled about this change. Turn signals are a conditioned part of the human mind for those who ride in a car regularly.
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Taking a turn without one feels strange and odd, and not hearing it click while activated could set off some alarms for riders, who might use the noise as confirmation that other drivers know of their intention to turn.
I kind of like it being on, threw me off when riding with Zoox who has had it disabled
— Dan Burkland (@DBurkland) July 27, 2026
Turn signal noises are still audible in customer cars, so if you use FSD in your personal vehicle, you will still hear the turn signal.
The move is certainly one that is unique, but not one that separates it from other ride-sharing services. In a normal car, the clicking sound confirms to the driver that the blinker is active. In a fully driverless Robotaxi, that feedback serves no purpose for passengers, other than peace of mind.
Tesla Summer Update begins rolling out: a look at the new features
Tesla briefly offered this Robotaxi part for your personal car
