News
Tesla Model S Drive Unit Replacement by the Numbers
During my early days of researching the Tesla Model S, I had concerns about a number of things that were emerging in the press. Fires, Model S drive unit issues, and handling in the snow. Tesla quickly addressed the “firegate” issue by retrofitting the Model S with a titanium shield. My concerns around winter driving, in particular handling in the snow, also became a non-issue after watching several winter driving videos put together by Bjørn Nyland.
Within no time, I became a new Model S owner and quickly learned that driving in the winter could actually be quite fun with a good set of winter tires. Tesla later introduced the all-wheel drive “D” models putting to rest any remaining doubt that the Model S could be the best and safest handling car in the world.
But one question still remains for me, Has Tesla dealt with the Drive Unit issues?
Model S Drive Unit Replacement by the Numbers
There is a group of Model S owners across the forums, but also validated by major publications such as Edmunds, that have had one or more drive unit replacements.
Early reports of drive unit issues ranged from total failures that left the Model S inoperable, to more recent complaints of clunking and milling noises. Elon has said in the past that many of these pre-emptive drive unit replacements were unnecessary and a simple $0.50 shim was all that was really needed, yet Tesla Service centers have been proactively replacing drive units.
The following polls from TMC show that a majority of Model S owners have had their drive units replaced.
While the poll only represents a small sample of Model S owners, one might draw significance in the numbers as the density circles around owners needing a drive unit replacement at relatively low mileage, and without any harsh driving prior to failure.
The polls also give insight to the motive behind each drive unit replacement.
Though it appears the issues mainly center around earlier versions of the Model S, there’s been reports of newer Model S with Autopilot hardware hearing milling noises coming from the drive unit. One viewer described the sound as “sawing wood”.
Tesla’s Response to Drive Unit Issues
In typical Tesla fashion, the company acted fast to address the issues, and curb concerns by offering an unlimited mile/8 year warranty on the drive unit. I think this was a great response by Tesla which put to rest any concerns about the quality and long term durability of their drive units.
Elon is now talking about building a power train that will last a million miles and I believe Tesla continues to put significant energy into improving the drive units. Tesla continues to honor the warranty and is proactively replacing drive units that show early signs of problems.
My Experience
After 12 months of Model S ownership and 30k miles drive, I started hearing a humming noise from the rear of my Model S during highway cruising. The noise was unusual as I had gotten used to hearing only the noise of the tires and wind, but there was a new noise only noticeable when cruising or decelerating with regeneration at 65 MPH and over. The noise continued to become more audible over the next few months, but I learned to live with it and did not contact Tesla. My personal rule of thumb on noise related issues is to wait for passengers to comment on it first. It’s my self crazy check.
Two months after the original drive unit humming noises began, a higher pitched milling type noise started occuring when traveling at speeds of 20 MPH or less. The sound varied depending on how much power was being used. That’s when I reached out to Tesla.

Tesla service record
Tesla service had me come in for a test drive which they can do on demand without you needing to wait. We drove about a block before the Tesla service technician said the drive unit needed to be replaced.
The explanation was that tolerances inside the drive unit have led to metal particles getting into the fluid around the drive unit, and as the concentration of particles increased, it caused the noise from the drive unit to become louder when under load. The new drive units evidently have better tolerances and are less prone to having metal particles being shaved off.
At that time, Tesla service has been very backed up here in Massachusetts so my appointment for the drive unit replacement was scheduled six weeks out. I put on another 4,000 miles during that wait time, with an increasingly louder drive unit, before it was finally replaced.
When Tesla replaces a drive unit, they replace both the drive unit and inverter as you can see from a copy of the parts list. The last letter in the drive unit part number (“M” in my case) seems to indicate the generation of the drive unit. The later the letter the better, with the “Q”s seeming to have the best longevity according to the forums.
I’m happy to say that I’ve logged 8,000 miles of happy and noise-free driving after my drive unit replacement. The replacement was done recently so my guess is that I have a newer unit, and thus hope this will be my only replacement.
Thankfully for all of us, Tesla has a first class warranty and level of service. While it goes without saying that inconveniences such as this may happen, rest assured that Tesla has you covered and will always strive to make things right.
Investor's Corner
Tesla has one big financial question to answer for investors: Morgan Stanley
In a new note to investors on Tuesday, Morgan Stanley analyst Andrew Percoco said that Tesla has one big financial question to answer for investors regarding its Robotaxi rollout, Full Self-Driving software, and Optimus.
Percoco said in the note that, for the most part, investors are still very positive about the direction the company is headed. However, there are some things the firm would like to see, and they have to do with financials.
Tesla (TSLA) Q2 2026 earnings results: miss on EPS, beat on revenue
Tesla bulls are more than convinced that the company’s Full Self-Driving software is proof it can develop physical AI. Financially, however, there are still some questions, especially on elevated spending, which CEO Elon Musk said would occur as the company works to roll out Robotaxi faster and continue developing its Optimus robot.
The latter two are where Tesla will have to prove progress to investors, as Percoco writes that both projects “will require clearer evidence that Robotaxi is scaling and more tangible Optimus proof points to support the ROI on elevated capex.”
Percoco said the second quarter earnings call did not change his long-term thesis of where Tesla is positioned in the AI race, which is out in front. However, there are concerns that weaker gross margins and higher R&D spend will stress financials, and that has “sharpened our (and investors’) focus on measurable progress across Robotaxi and Optimus.”
Additionally, Robotaxi still needs to be proven with more operation in existing cities while maintaining safety but improving how many rides it gives in any given time, he said. For Optimus, Percoco wrote that he is “still looking for evidence beyond commentary around SOP.”
Morgan Stanley put Percoco in charge of covering Tesla after long-time analyst Adam Jonas transitioned to the automotive side.
Currently, Morgan Stanley has a $415 price target on Tesla and a ‘Hold’ rating on the stock. It is trading at around $330 at the time of publication, which was 2:30 P.M. on the East Coast.
Investor's Corner
SpaceX AI investment gamble will make it a big winner, firm says
SpaceX’s massive investment in AI will make it a big winner, Argus Research said after the company’s successful earnings call last week.
The firm also upgraded shares to a Buy from Hold and set a $160 price target.
SpaceX (NASDAQ: SPCX) is currently recovering from its heavy AI infrastructure investments, as it spent nearly $16 billion in Q2 alone. The company did this primarily by monetizing high-demand GPU compute capacity at a much faster pace than traditional data center economics would suggest.
Company CFO Bret Johnsen said that SpaceX would be able to pay back anything on new deployments within a year.
There are plenty of ways the company can do this:
Leasing excess compute capacity through contracts
SpaceX has already built Colossus and Colossus II, largely for its own model training. However, much of that capacity is already rented out to third parties. It already has major deals with Anthropic, Google, and Reflection AI. These partnerships are adding billions per month to SpaceX’s spreadsheet.
High utilization driven by industry-wide scarcity
The demand for advanced AI training and inference capacity continues to exceed what is available for use. SpaceX can fill new racks quickly after they come online, so the capital deployed converts into revenue with minimal idle time.
Additionally, management and outside observers have described the new compute capital as behaving more like a cost-of-goods-sold than traditional multi-year capex, especially because of this rapid monetization pattern.
Capacity has already scaled from ~0.4 GW a year to 1.4 GW annually by the end of Q2. There are targets of more than 2 GW by year-end.
High incremental margins on the rental business once capacity is online
GPU cloud providers often operate at strong gross margins. SpaceX can monetize capacity that was already partially built or can be added efficiently. This means that incremental EBITDA margins on the rental revenue are usually high. This accelerates cash recovery relative to the gross capital outlay.
Parallel monetization of its own AI software and applications
Beyond pure infrastructure rental, SpaceX also generates revenue from Grok through subscriptions and usage, from X through ads, data, and other related services, enterprise APIs, and the planned integration of the Cursor coding tools acquisition.
These application layers ride on the same compute infrastructure and provide additional high-margin streams that could offset build-out costs. AI-segment revenue overall rose sharply to about $2.6 billion in Q2, according to Motley Fool. This was driven primarily by the infrastructure contracts, but the software side is also partially responsible.
Efficient, large-scale deployment and vertical integration advantages
SpaceX has emphasized the rapid construction of power and cooling infrastructure and favorable cost-per-megawatt economics relative to industry benchmarks in some disclosures.
Combined with its ability to scale capacity aggressively and the fact that many contracts start generating revenue within months of capacity coming online, the effective payback compresses dramatically compared with more conventional multi-year data-center projects.
SpaceX’s dominant near-term recovery path will turn the AI clusters into a hyperscale-style compute rental business for other leading AI companies while still using a portion for internal models.
News
Tesla headlights cause recall of over 20,000 Model 3 and Model Y
Tesla headlights have caused a recall of over 20,000 of the company’s two most popular vehicles, the Model 3 and Model Y, due to the low-beam bulb exceeding the maximum allowed intensity according to federal standards.
Tesla initiated the recall with the National Highway Traffic Safety Administration (NHTSA) this morning, stating that the low-beam output “exceeds the maximum allowed intensity in the outer upper-right and outer upper-left areas of the 10U and 90U zone, as prescribed in FMVSS No. 108.”
Tesla sourced the impacted headlights from Marelli Automotive Lighting, a Mexico-based company. The recall impacts 2020-2023 Model Y vehicles and 2017-2023 Model 3 vehicles. It is estimated that every VIN in this recall is impacted by the defect.
🚨 Tesla is recalling 20,349 2020-23 Model Y vehicles and 2017-23 Model 3 vehicles due to an excessively bright headlamp low beam.
Currently, there is no remedy plan in place, as it is still being developed. pic.twitter.com/y34cIO2U0B
— TESLARATI (@Teslarati) August 11, 2026
Typically, Tesla would remedy recalls of this nature through an Over-the-Air software update, which has been a major focus of criticism by the company and its supporters because the NHTSA still refers to it as a “recall,” even though it requires no action by the vehicle owner. The fix is shipped over the internet and downloaded to the car.
However, there appears to be a potentially different solution for this problem. Tesla has not developed a remedy for this issue, so it could potentially be on the way. The big issue appears to be the fact that these recalled lamps are out of production, and this is an old body style for both vehicles. The headlights and front-end designs are completely different.
Tesla switched to another supplier when the affected headlight design was discontinued. It plans to begin notifying owners of their remedy options by September 15.
Tesla filed a petition protesting the recall to fix the vehicles’ headlight issue, but the NHTSA denied it. Now, Tesla will come up with a solution to fix it.



