It’s been nearly 10 years since controversial and edgy zero emission vehicle maker, Tesla first announced it was building its take on an all electric prime mover, which it creatively called, the Semi.
As is. the brand’s want many a claim has been made about the capabilities and potential uses for its Semi in the past decade, often with some what seemed like wildly optimistic claims of performance and weight hauling capabilities.
To introduce some seemingly unjaundiced eyes and a different take on the big truck, leading US car magazine, Motor Trend has just published a road test of the Tesla Semi, three and a half years after it took its first look at the truck with a car testing view.
At that time and since then Tesla has had the Semi working for the PepsiCo. in the US and most particularly its potato chip operation, Frito-Lay. As some industry observers have opined, potato crisps aren’t exactly a heavy duty consignment making a up a lot of volume but not a lot of gross weight.
As Motor Trend explained in its intro, the Tesla Semi is a “purpose-built, all-electric big-rig meant for heavy-duty commercial hauling”.
As we said the magazine had a preview of the truck back in early 2023 when the electric vehicle maker gave it an in-person update on the state of truck’s pilot program which comprised almost 200 trucks with the FritoLay division of PepsiCo.
Back then Motor Trend got to inspect the pre production versions of the Semi but didn’t get to steer the battery powered prime mover.
The difference this time was that Motor Trend actually got to drive the truck as well as inspecting the company’s brand new factory in Nevada where it claims the Semi will go into series production next year.
Motor Trend gave its readers a a quick primer on the nature of the beast that are semi-trucks, also known in the States and other places as big-rigs or 18-wheelers.
In the USA these Heavy Duty models as we know then are of course classed as ” Class 8 tractor-trailers” and in that country at least are the heaviest commercial vehicles on the road nt he USA and included trucks with what they describe as a gross vehicle weight rating or GVWR which exceeds 14.7 tonnes in our language or 33,000 pounds in the land of the Trump.
Tesla has packaged its Semi with a GVWR or what we call Gross Vehicle Mass or GVM, in its heaviest, long-range, three-battery-pack configuration, with a GVM of 21.7 tonnes or 48,000 pounds and endorses it wth a gross combination mass or as they call it a gross combined weight rating (GCWR) of 37.2 tonnes (or 82,000 pounds int he US. As most in the idustry here would know this includes the weight of the truck and trailer and everything inside. Of course in Australia that is not a lot even for a single semi trailer combo, which normally have a GCM limit of around 42.5 tonnes or so and a little bit more under certain allowances such as PBS.
Motor Trend did mention that in the US at least, battery electric trucks are allowed an extra 900 odd kilograms or about 2000 pounds to compensate for the battery weight imposition. That’s not a lot, in the bigger scheme of things, especially the way our trucks are loaded in this country.
As Motor trend tells us , moving that sort of weight takes a fair bit of energy, and requires a. fair bit of battery power to move things along, even if the wrights are well below the expectations we have for heavy trucks Down Under.
The magazine points out that the “Tesla Semi’s battery packs are situated low, between the frame rails and that they power three permanent-magnet electric motors, which have been derived from the company’s interestingly named Plaid and Cybertruck light vehicle drive units. These power the two rear drive axles on the Semi, with naturally enough the front axle primarily being for steering, making the Tesla Semi a classic 6×4.
The Tesla Semi uses the front axle of the rear tandem as a torque drive axle which is activated when maximum torque is needed, like under hard acceleration and when climbing grades.
The magazine points out that at normal, steady highway speeds, the two-motor torque drive axle disengages to reduce drag, which then allows the rear drive axle to be the sole power for the truck.. This means the single-motor rear drive axle is always on, while the forward torque drive axle are only put into action when needed. Tesla’s engineers claimed to the magazine that they wouldn’t be able to feel any kind of change when the two different drive programs are in use.
Motor Trend’s test driver reckons one big difference between the pilot trucks it viewed back in 2023 and the production Semi is that the last incarnation uses the same Tesla 4680 batterie that are used in the polarising Cybertruck pick up .
These batteries are arranged in eight “bandoliers” of 28 cells for each battery module, and 14 modules are in each pack, with the long-range Semi using three packs to achieve a total of 850-ish kWh of power or a claimed 800 kilometres of driving range. The article points out that the standard-range Tesla Semi is equipped with only two battery packs for about 500km (325 miles) of claimed driving range.
Tesla claims the batteries are rated for around 1.6 million kilometres of use and the company claims it can be recharged from near zero to 60 per cent in about 30 minutes.
Tesla claims the truck has a maximum power output of about 1,076 horsepower in the old language and of course being electric 100 per cent of torque is available at star up..
Motor Trend reported that at the launch event it attended, Tesla plugged in one of its Semis at the start of a keynote address by the company’s vice president of vehicle engineering, Lars Moravy, along with its program director for the Semi, Dan Priestley, pointing out that at various points during the program, the two executives cut to the live feed of the Semi charging to show that it was charging at close to its 1.2-megawatt (1200-kW) limit.
The magazine pointed out that while that charging rate tapered off, the truck’s state of charge showed well over 60 per cent before the roughly 40-minute presentation finished.
The road tester conducting the road test on the Semi was apparently well versed in the Tesla ecosphere, and in fact has logged almost 16,000km at the wheel of the magazine’s 2023 long term Tesla Model Test car. However he admitted that his experience in heavy trucks was almost zilch and that the heaviest ‘trucks’ he had tested were that breed of US Utes or pick ups we are now well familiar with, such as heavy duty versions of Ford F Series, Chevy, GMC or Rams, in other words things with a GCM of bout six tonnes not 36 tonnes.
He admitted that he had never driven anything as heavy as the loaded Tesla Semi.
“So I was a big-rig rookie, and yet, driving the Semi was surprisingly familiar, shockingly easy, and dare I say, several tons of fun,” the Motor Trend tester admitted.
The tester said the procedure for settling into the cab and getting underway witht he controls etc was remarkably like the procedures needed for starting one of the company’s battery electric light vehicles.
The Tesla Semi features a central sitting position for the driver, with a single passenger’ jump’ seat situated against the rear cab wall behind the driving position.
He commented that the controls in the Demo cable eerily like those in the Tesla car range with the steering wheel, screens, and levers all looking a lot like those used in the Tesla Model 3, Model Y and Model YL, describing them as looking like they had been repurposed from these.
Controls for adjusting the the driver’s seat and mirrors, are handled on the left hand touchscreen or using steering-wheel rollers.
When ready to get underway it is a matter of pushing down on the brake pedal and then pushing the end of the gear selector stalk on the righthand side of the steering column.
Like contemporary trucks fro the likes of Daimler and more recently Volvo and other Euro brands, the Tesla Semi uses mirror cameras with LED screens inside the cabin giving the driver views of what is behind him and potentially in any blind spots. There are four views from the four cameras which are viewed on a pair of 16.0-inch screens mounted on the left and right sides of the steering wheel.
The tester reckons that the truck’s acceleration was smooth, with shiftless progress and what he described as a ‘light yet direct control of the electric power steering’, which he said reinforced the ‘Tesla-ness’ of the truck.
the tester didn’t exactly have a long experience at the wheel of the Tesla truck, he only spent about 12 minutes behind the wheel of the Semi at the company’s small test track located next to its so called Gigafactory where the Semi is built outside Reno, Nevada.
Interestingly he praised the truck’s independent front suspension design and particularly the attention that he said Tesla engineers had paid to increasing the steering angle of the front wheels, which he said has given the Semi an impressively tight turning radius.
He tells us that the company claims the Semi without a trailer only needs a little more room to make a U-turn than one of its Model Y passenger cars, but this probably belied his lack of heavy truck experience, with most bobtail prime movers hving pretty reasonable turning circles.
So here is the other rub, it wasn’t exactly a thorough test as during his short drive he was only able to get up to around 60km/h while shuttling between Tesla’s factories, but did say that he encountered some patches of surprisingly rough pavement that sent lot of noise and vibration up through the cabin despite airbag suspension at all six wheels. But as down under truck operators would know, this guy ain’t seen nothing and he would be absolutely beside himself if head to tackle any of our rough and ready, potholed tarmac roads across this Wide Brown Land.
In fairness the Motor Trend tester did not rely on his own less than developed knowledge of heavy truck and roped in a fellow journo and truck tester from a US based global supply chain, transportation, and logistics 
media outlet called FreightWaves.
That journo who is apparently a veteran truck driver with more than 1.6 million kilometres at the wheel of heavy duty trucks ws granted permission to take the Tesla onto public roads and with a trailer attached. Even then it wasn’t a run up the interstate from LA to San Fran, but a slightly longer 25 minute spin with a payload of around 16.7 tonnes giving the rig a GCM of about 33.5 tonnes, which was only about 90 per cent of the trucks maximum allowed GCM.
That real truck driver said he was surprised at how smooth the Semi drove and how quickly he became accustomed to the central driving position. However his biggest surprise was when he drove the Semi as a bobtail and then with 16 tonne payload aboard.
He commented on the truck’s torque making it feel like he wasn’t towing anything at all. He was apparently equally surprised at the performance of the Semi while climbing a seven to eight per cent incline h. He said that after coasting at about 60km/h he then whomped on the throttle and said that it pulled like there was nothing behind it at all, commenting that in climbing the grade in under a minute, the truck only dropped about 2km/h to 58km/h and took it up to a speed of around 90km/h.
According to Motor Trend Tesla’s launch event marked the official start of customer deliveries for what it calls the 2027 Tesla Semi, with the company’s first customers, including US Foods, IMC Logistics, Arkansas Best Freight (ABF), HMD Trucking, WattEV, DHL, OK Produce, Einride, Nevoya, Lincoln Trucking Systems (LTS), and PepsiCo on hand to receive the keycards for their trucks.
Tesla was coy about the pricing of its first production delivered Semis with the company declining to give an exact figure, simply explaining that it “won’t cost any more than a diesel truck”, citing customer negotiations and various incentives offered by the different US states in which the company is operating. The Tesla execs also told the gathered media that the Semi would be cheaper to operate, refuel, and maintain than traditional diesel-powered trucks.
During that adventure, we got to crawl all over and inside the preproduction Semi but not drive it. This time around, I not only got to drive the Semi, but also got to see the automaker’s brand-new factory in Sparks, Nevada, where the production 2027 Tesla Semi is being built. Before we detail our latest experience, let’s review some big-rig basics.
How the Tesla Semi Works
First, a quick primer on semi-trucks, aka big-rigs or 18-wheelers. The official name is a Class 8 tractor-trailer; they’re the heaviest commercial vehicles on the road, as defined by a gross vehicle weight rating (GVWR) exceeding 33,000 pounds.
In its heaviest, long-range, three-battery-pack configuration, Tesla Semi has a GVWR of 48,800 pounds and gross combined weight rating (GCWR) of 82,000 pounds, which includes the weight of the truck and trailer and everything inside. Those 82,000 pounds are the limit set by the manufacturer, and government agencies use it to determine legal and commercial weight compliance. The typical diesel-powered tractor-trailer has a GCWR of 80,000 pounds, but electric big rigs are allowed an additional 2,000 pounds for their batteries.
Moving all this weight takes a lot of energy, and the Tesla Semi’s battery packs are situated low, between the frame rails. They power three permanent-magnet electric motors, derived from the Tesla Plaid and Cybertruck drive units, to power the two rear axles. The wheels on the front axle are for steering, making the Tesla Semi a classic 6×4: six wheels total, four of them powered. To further clarify, the dual rear wheels on both back axles are counted simply as wheels in this case.
