Tesla Semi Deleted ALL Hydraulics & AC Lines… Here's the INSANE Engineering Inside!

Uh this is really going to be a revolutionary truck, uh that uh is capable of carrying the heaviest loads over very long distances.

This is the front axle of the commercial version Tesla Semi. No oil pump, no hydraulic hoses. A FreightWaves driver test drove it and confirmed it.

hydraulic hoses. A FreightWaves driver test drove it and confirmed it.

The entire truck no longer has a single hydraulic oil line.

The Semi project lead said the truck also wipes out the air conditioning gas lines that run up to the cab. And yet, the truck still has power steering, and the cab still has air conditioning. It's just that the way Tesla does it is

completely different. Last week, Tesla officially hit the

completely different. Last week, Tesla officially hit the button on mass production of this machine.

They have a catchphrase. The best part is no part.

But, on a rig weighing 41 tons when fully loaded, is removing components a real technical advance, or just a way to make the truck cheaper? The evidence

lies in each component that was removed, a filing submitted to a California regulatory agency, and real-world data from freight carriers.

Let's start with what's right in front of the driver, the steering wheel.

Looking into the cab, the first thing a driver puts their hands on is the steering wheel. To understand what Tesla has deleted,

steering wheel. To understand what Tesla has deleted, let's look at what a conventional Class 8 truck hides behind it. That is, a hydraulic power assist system. A pump, continuously driven by the engine,

pushes high-pressure oil to the steering gear.

US patents on power assist pumps describe this very plainly. The pump is always engaged with the engine to maintain high-pressure oil flow, while the driver doesn't always need assistance. In other words, the pump

becomes a parasitic loss whenever the truck isn't being steered.

The trucking industry has tried to improve on this. Since 2012, Volvo has used Volvo Dynamic Steering on its trucks. This system adds an electric motor that works alongside the hydraulic power assist with a maximum torque of 25

Newton meters and is controlled 2,000 times per second. But note this detail.

When a serious fault is detected, the system shuts off the electric motor and the hydraulic power assist keeps working as it would on an ordinary truck.

That is the whole industry uses electricity as an addition [clears throat] while hydraulics remains the safety net.

Tesla pulls that safety net out all together.

On the commercial version, the steering is fully electric, redundant, and there is no hydraulic circuit anywhere on the truck. Tesla claims the Semi is the first heavy-duty truck with electric steering, lighter, quieter, more

precise, and redundant by design. Now we understand why the word redundant matters so much. With no hydraulics left to fall back on the backup has to sit inside the electrical system itself.

Tesla has not published the detailed architecture of this backup, so it is something to keep watching. So how does it drive?

The most credible person to answer is someone who was once a skeptic.

Adam Wingfield of FreightWaves has held a Class A license with a hazmat endorsement for most of his adult life, nearly three decades in the trade, and was one of the loudest critics of this truck. Then he drove it fully loaded. He

wrote that the steering responds faster and more precisely than any Class 8 truck he has ever driven. And combined with the steering angle that Tesla says gives a turning radius close to a Model Y's maneuvering in tight spaces is no

longer a negotiation. To him, that is the difference between coupling the trailer in a tight yard on the first try and having to get out and check three times. He also pointed out something every driver takes to heart. No

times. He also pointed out something every driver takes to heart. No

hydraulic steering system means no power assist fluid leak to hunt for during the pre-trip inspection. Tesla also says electric steering lays the foundation

pre-trip inspection. Tesla also says electric steering lays the foundation for autonomy because a computer can command a motor, but cannot command an oil pump. Even so, no timeline has been announced. This is a direction, not yet

oil pump. Even so, no timeline has been announced. This is a direction, not yet a feature. Steering is a control problem. The harder problem is heat. A

a feature. Steering is a control problem. The harder problem is heat. A

diesel truck never runs short of heat. According to an energy analysis from West Virginia University published by the ICCT, a reference heavy-duty diesel engine converts only 39.1%

of fuel energy into useful work with 35.5% lost through the exhaust and 10.6% lost to the coolant.

Newer engines do better. Heavy-duty diesel engines in production reach a thermal efficiency of 43 to 46%. That means more than half of the diesel's energy still becomes heat. A diesel truck's cab is heated by a

small portion of that heat. Electric vehicles are the reverse. There is much less excess heat, but the thermal load is very large.

Tesla announces 800 kW of traction power from three independent motors at the rear and the truck recharges 60% in about 30 minutes at 1.2 MW.

All of that has to be cooled while the cab still needs heating in winter.

In a presentation recorded by Not a Tesla App, Moravian Priestley said the engineering team initially tried fitting two Model 3/Y heat pumps into the semi, but this approach was inefficient for the enormous cooling load of a Class 8

vehicle. So, they built the mega manifold. The idea has a precursor on

vehicle. So, they built the mega manifold. The idea has a precursor on the Model Y. Tesla designed a super manifold that merges all the refrigerant channels and coolant channels into one block together with an octovalve that

turns to different positions depending on the operating mode. The mega manifold is the truck version. According to Tesla, it is a new generation heat pump that runs the cabin air conditioning and all heating and cooling of the

drivetrain at the same time. A heat pump is like an air conditioner running in reverse. It carries heat from a colder place to a warmer place instead of

reverse. It carries heat from a colder place to a warmer place instead of burning energy to create heat. Thanks to this, according to Tesla, the semi can take excess heat from the drivetrain to keep the driver warm. And

this is the answer to the words AC lines. Priestly said at the event, "No AC lines, no refrigerant lines. The indirect thermal system is filled and sealed at the factory, exchanges only coolant, and does not bring refrigerant

to the front of the truck." Wingfield confirmed this from the perspective of the person inspecting the truck. The refrigerant lines running up to the front, as on a conventional truck, are gone. Imagine a sealed air conditioning

unit placed in the basement, pumping only warm water and cold water up to each room. Tesla has not published any figures on how the system performs at

each room. Tesla has not published any figures on how the system performs at sub-zero temperatures. The first winter will be the real test. So, the two

sub-zero temperatures. The first winter will be the real test. So, the two things deleted in the title now have their answers. In both cases, deleting is not cutting back. But there is one more detail. The semi shares its thermal

management system with the cybercab, including the pumps, compressor, and heat exchangers. Tesla calls it one thermal system for both the company's

heat exchangers. Tesla calls it one thermal system for both the company's most efficient vehicle and its largest. If the things exposed on the outside have been redone this thoroughly, then inside the motor and the battery pack,

where no one can see, what else has Tesla quietly deleted? The rotor is the rotating part of an electric motor. On high-performance motors, it is wrapped in carbon fiber to keep the magnets in place when spinning very fast. The old

semi used that approach. The commercial version replaces it with a steel cage rotor, and Tesla says it is cheaper, more durable, and more efficient. The

stator, the stationary part containing the copper windings, is now shared with the Cybertruck, a design that has been proven and is in mass production.

It sounds like a step back to a less premium material.

In reality, Tesla is trading a specialized component for one that already has a production line. Then there is the oil.

Moravy said the wheel hubs no longer have oil, while the gearbox and motor share one type of oil that lasts more than 250,000 mi.

Wingfield confirmed this from the driver's perspective. Three types of oil are now just one, and the hubs run dry. Every type of oil that disappears is one less line in the maintenance logbook. But a beautiful design on the drawing

board is easy. The real question is, can thousands of them actually be built? Tesla says most truck factories only assemble. In Nevada, by contrast, they stamp their

assemble. In Nevada, by contrast, they stamp their own parts and make their own batteries, axles, high-voltage distribution units, cooling modules, even the seats. The company holds that vertical

integration is the only real way to bring costs down.

Priestly described it. Coiled steel comes in and is cut and stamped right on the spot. Battery cells that Tesla makes itself at Gigafactory Texas are unloaded automatically from the trucks and fed straight onto the line with no human hands touching them.

Design scale. 50,000 trucks per year on 1.8 million square feet. For comparison, Daimler trucks sold

square feet. For comparison, Daimler trucks sold 141,000 trucks in North America in 2025.

But 50,000 is capacity, not output. Musk himself said initial production will be very slow and only then ramp up exponentially.

And here is the most important change. Tesla is switching from purchased 2170 cells to self-made 4680 cells and says this allows a lighter battery with fewer

kilowatt hours while keeping the same range.

How many fewer? In December 2022, Musk said the battery for the 500-mile version would be around 900 kilowatt hours.

Then the CARB filing A-374-0095, signed April 15th, recorded the real figures. 822 kilowatt hours usable for

the long-range version. 548 kilowatt hours for the standard range version with NCMA chemistry and 4680 cells. That is about 80 kilowatt hours smaller,

yet Tesla still rates it at 500 miles at a gross weight of 82,000 pounds.

Do the division. 822 kilowatt hours over 500 miles is about 1.64 kilowatt hours per mile. Put that next to the competitors.

The Freightliner eCascadia travels about 230 miles with a maximum 550 kilowatt hour battery. The Volvo VNR Electric about 275 miles

hour battery. The Volvo VNR Electric about 275 miles with 564 kilowatt hours. A smaller battery means less material, less weight, and better economics for the buyer.

This is exactly where everything deleted in module A adds up. Every watt not wasted is a kilowatt hour of battery you don't need to carry. But 1.64

is still a calculation on paper. What about on the real road? ABF Freight ran a trial of one semi for 3 weeks. 4,494 miles averaging 321 miles per day,

consuming 1.55 kWh per mile, including the climb over 7,200 ft Donner Pass. ABF's president was clear. They were not looking for a truck that is good compared to electric vehicles,

but one that must match or exceed their most efficient diesel. DHL measured 1.72 kWh per mile, and according to DHL itself, this result surpassed even the

level Tesla published. Pepsico recorded 1.7 in NACFE's program. Sysco reached

1.73. These were all pilot generation trucks, and after the trial, ABF paid to buy two. Money is starting to flow. The ZED

scale coalition, with members such as Microsoft and Pepsico, chose Tesla as the primary supplier for 2,500 electric trucks. Kenworth, Volvo, and Ride are

secondary suppliers. So, not all 2,500 units are semis. This order alone is

secondary suppliers. So, not all 2,500 units are semis. This order alone is nearly double the number of class 8 electric trucks currently running on US

roads. Before that, Einride ordered 500 units.

roads. Before that, Einride ordered 500 units.

Watt EV ordered 370 units valued at about $100 million.

So, how much does the truck cost? Tesla has not officially announced it.

Electrek reported that Tesla quoted $290,000 for the long-range version and about $260,000 for the standard. That is about 60% higher than the $180,000 Tesla advertised in 2017, but still

about $145,000 lower than the average price of a class 8 electric truck. Why would a freight carrier be willing to pay more than for a diesel? Look at the cost breakdown. According to

the American Transportation Research Institute ATRI, in 2025, the operating cost of an average truck was $2.336 per mile, the highest ever. Driver wages

and benefits exceeded $1 per mile for the first time at $1.028.

Fuel is about 48 cents. Repair and maintenance was 19.8 cents in 2024, then rose another 8.6% in 2025 to about 21.5 cents. Meanwhile, the profit margins of

full truckload carriers remain below 1%. Read this breakdown carefully. The

largest item, the driver, accounts for about 44% and the semi doesn't touch it at all. The truck still needs a driver. What it targets is fuel plus

at all. The truck still needs a driver. What it targets is fuel plus maintenance, about 70 cents per mile, nearly 30% of total cost, and that is exactly where the deleted items take effect. No hydraulic oil, no gas lines,

one type of oil instead of three. Wingfield also added regenerative braking. He almost never has to touch the service brake, meaning brake pads,

braking. He almost never has to touch the service brake, meaning brake pads, drums, and the compressed air system may need replacing less often. But he

declined to give a figure because no one has the data yet. For drivers, the job changes rather than disappears. A quieter cab, personal profiles that follow them automatically from one truck to another, less need to crawl under the

truck during pre-trip inspections. In an industry where margins are below 1%, a few cents per mile is no small matter. So, the truck is ready. But even

Wingfield, who has just changed his mind, still has two doubts, and neither is inside the cab. The first is weight. The long-range version weighs about

23,000 lb when unloaded. The standard is under 20,000 lb. Both are rated at the full 82,000 lb thanks to the 2,000-lb allowance that federal law grants to electric trucks. For heavy cargo, the payload ceiling is

electric trucks. For heavy cargo, the payload ceiling is therefore lower. The second is charging stations. Recharging 60% in about 30

therefore lower. The second is charging stations. Recharging 60% in about 30 minutes at 1.2 MW sounds very good on paper, provided the station is where it's needed, is working, and nobody is occupying the spot. His conclusion,

the truck has come further than he expected, but the infrastructure has not. And no technology inside the cab can make up for what is missing outside.

not. And no technology inside the cab can make up for what is missing outside.

If charging stations are not present where the truck needs them, is every component Tesla removed still worth it? To answer, we have to put two numbers on the table, the fuel cost and the electricity cost.

Number one, the fuel cost. During the week of the Nevada event, the US national average diesel price, according to the EIA, was $6.52 per gallon, exceeding the previous peak of $5.81

in June 2022. In the same period last year, this figure was only about $3.75. This is a nominal record.

Adjusted for inflation, the 2008 peak is equivalent to about $7.20 in 2026 dollars, and the 2022 peak to about $6.56.

Tesla calculates for a diesel truck running 7 mi per gallon.

Divided out, fuel cost alone is about 93 cents per mile.

Number two, the electricity cost. And this is where the story gets interesting, because the electricity cost is not a single number.

The chart Tesla showed at the event puts the electricity cost at transportation rates in the range of 20 to 30 cents per mile.

But in July, the commercial electricity price in California was 30.56 cents per kilowatt-hour, more than three times the 9.72 cents in Nevada. Multiply by 1.7

kilowatt hours per mile. Charging at a depot in Nevada costs about 17 cents per mile. In California, about 52 cents.

As for public stations, Tesla has not published a price per kilowatt hour.

Electrek has warned that prices there could easily exceed 50 cents per kilowatt hour, or about 85 cents per mile, nearly equal to the fuel cost. The

same truck, the same 1.7 kilowatt hours per mile, but the energy cost swings from about 17 to 85 cents, five times over, depending only on where you plug in. With today's record diesel prices, the

in. With today's record diesel prices, the semi wins in almost every scenario. But if diesel returns to last year's $3.75, or about 54 cents per mile, a semi that

has to charge at an expensive public station would lose.

And that calculation doesn't yet include demand charges, the fee calculated on the maximum power a facility draws from the grid, which can make up most of the bill at megawatt scale charging stations.

Tesla understands this well. That is why the most important news on the night of the event may not be about the truck. Tesla executives said the company will deploy 30 megacharger sites with a total of 200 megawatt class charging posts in

the US before the end of this year, and that this network will be open to other manufacturers electric trucks as well, the way Tesla once opened its supercharger network. In July, Tesla opened its first full

supercharger network. In July, Tesla opened its first full power public station in Bloomington, California, with six charging posts, each up to 1.2 megawatts. The old station in Ontario, with only

two 750 kilowatt posts, has been taken off the map.

In August, the second station in Vernon went into operation with a similar configuration. That means that today, there are two public stations running at

configuration. That means that today, there are two public stations running at full power, both around Los Angeles. The promise is 30 stations before December

31st, with less than 3 months left. Tesla is using three levers at once to close that gap. First, the company is partnering with the Pilot Travel Centers truck stop chain to place four to eight mega charger posts at some locations

starting in the summer. Second, fleet owners can buy two mega charger posts for their own yards at a starting price of $188,000.

Third, the person in charge of Tesla's charging rollout in North America stated the strategy clearly. Prioritize the most important routes and yards first, while recommending that customers with the means install charging

infrastructure at their own yards. That is a credible plan in terms of direction. But 30 stations before year end is still a projection. And Tesla has

direction. But 30 stations before year end is still a projection. And Tesla has a history of being late with this very semi. What has been proven is fairly

solid. Mass production has started. The CARB filing confirms the 822 kWh

solid. Mass production has started. The CARB filing confirms the 822 kWh battery. Four independent fleets measured consumption levels from 1.55 to

battery. Four independent fleets measured consumption levels from 1.55 to 1.73 kWh per mile. A once skeptical driver has personally confirmed the

truck has no hydraulics and no gas lines. And the first 1.2 MW charging stations are actually operating. What has only reached the stage of Tesla's

word needs to be treated exactly as that. Tesla says the semi fleet achieved more than 98% operational uptime in 2026, and that the truck needs almost no maintenance. But there is no independent

verification yet. The steel rotor is said to be more efficient, but no

verification yet. The steel rotor is said to be more efficient, but no figures accompany the claim. The mega manifold has not a single figure for winter. The capacity of 50,000 trucks per year,

30 charging stations before year end, and self-driving on the semi are all still projections. And statements such as "Diesel is dead",

still projections. And statements such as "Diesel is dead", "All 2,500 Z scale trucks are semis", or "Goods prices will fall" are all exaggerations. So, where is the semi strongest? Where

exaggerations. So, where is the semi strongest? Where

the truck owner controls the outlet. Eletrek points out that short container routes around ports are where the semi fits best. Predictable routes, charging at the yard on return, heavy loads. At one yard in Southern California

alone, Forum Mobility says 25 carriers have reserved spots for more than 330 semis. And the company's CEO says operating costs are up to 30% cheaper.

semis. And the company's CEO says operating costs are up to 30% cheaper.

It is no coincidence that both of the first public stations are located around the Los Angeles ports. Is removing components a real improvement or just a way to make the truck cheaper?

It turns out that is a false choice. Everything removed, from the hydraulic pump, the gas lines, and two of the three types of oil to the carbon fiber rotor, is a point of failure gone. Fewer points of failure means less time

sitting in the shop, and less time in the shop means more freight hauling miles. In an industry with margins below 1%,

miles. In an industry with margins below 1%, cheap to build and cheap to run are the same goal. But Tesla can only delete what is inside the truck. What decides whether the semi wins lies

outside, the outlet, and the price of every kilowatt-hour flowing through it.

That is why a company famous for taking things away now has to build more.

200 charging posts, one at a time. If the charging stations appear on schedule, electric trucks will likely take over the seaport segment and regional routes first and only then spread gradually to long haul as the

network fills the gaps in the western mountain region and the plains.

If diesel prices keep fluctuating as they have this year, the stability of electricity prices may become as important a reason to buy as the per mile savings. Drivers keep their position behind the

mile savings. Drivers keep their position behind the wheel. The job just changes. And although this is only speculation,

wheel. The job just changes. And although this is only speculation, the work of mechanics may shift gradually from changing oil and replacing hoses to electrical and software diagnostics.

Tech Revolution always analyzes with verifiable data.

The next milestone is 30 mega charger stations before December 31st.

Do you think Tesla will make it in time? Leave your thoughts, like, and subscribe to follow along together.