“It is a beast” with a tri-motor system

Tesla has begun buyer deliveries of its Class 8 all-electric semi truck, revealing just a few new issues about its powertrain.

In keeping with the producer, the Tesla Semi is a “beast” with a complete energy output 3 times that of any diesel truck on the highway. Nonetheless, Tesla doesn’t say the precise peak or steady energy output quantity.

The excessive energy comes as no shock on condition that the automobile is promised to speed up from 0 to 60 mph (96.5 km/h) in simply 20 seconds (when absolutely loaded). By the way in which, absolutely loaded means 82,000 lbs (37,195 kg) gross mixed weight (GCV), as a result of the allowed GCV for BEV automobiles is 2,000 lbs increased than for diesel automobiles – 80,000 lbs.

That is most likely why a closely loaded Tesla Semi was capable of speed up simply when driving up a 6% grade in Donner Go within the northern Sierra Nevada, as proven within the video (37:30). The automobile simply handed one other semi.

Elon Musk provides that the Tesla Semi drives considerably like a standard truck, regardless that it’s greater and heavier.

Now let’s get into the main points. The Tesla Semi is supplied with a brand new tri-motor system, consisting of three unbiased electrical motors (in comparison with 4, that are anticipated for use in 2017 when the Semi was introduced).

The motors are, in fact, used to drive the 2 rear axles – 2nd and third – because the entrance axle has no drive.

The fascinating factor is that the electrical motors have rotors with carbon sleeves – similar to within the Tesla Mannequin S / Mannequin X Plaid launched in 2021 (see right here the presentation of the entrance motor and two rear motors). Which means Tesla put every little thing it had into maximizing the ability output of the ability unit.

Tesla Semi power units

The primary rear axle (or second axle when you choose) has a single electrical motor, completely engaged by way of a single-speed gearbox. It’s optimized for freeway driving.

In the meantime, two different electrical motors are used on the rear axle to drive the left and proper wheels individually. These two engines are optimized for acceleration and torque.

Relying on the circumstances (particularly velocity and accelerator pedal place), the 2 rear motors are routinely and seamlessly engaged or mechanically disengaged from the drive shaft to scale back vitality losses.

Here is the way it works:

It is essential to notice that the Tesla Semi used powertrain parts borrowed from its different electrical automobiles – together with electrical motors and inverters, a warmth pump system, and an infotainment system.

In fact, there have been modifications, however the general use of mass-produced elements allowed Tesla to attain a a lot increased degree of reliability in comparison with the choice situation of creating fully new methods for a comparatively small quantity automobile (in comparison with thousands and thousands of automobiles).


The powertrain of the Tesla Semi, as within the case of different trendy electrical automobiles, is absolutely ready for intensive restoration. The corporate’s check confirmed that it’s potential to go downhill with regenerative braking and that principally the mechanical brakes are chilly on the backside.

Tesla Semi (2022) specs:

  • Absolutely loaded at 82,000 lbs (37,195 kg) gross mixed weight
  • Vary: About 300 miles (483 km) or 500 miles (804 km)
    (two battery choices)
  • Power consumption: lower than 2 kWh/mile (1.24 kWh/km)
  • Estimated battery capability (primarily based on vary and energy consumption): lower than 600 kWh or 1,000 kWh (1 MWh)
  • Acceleration 0-60 mph (96.5 km/h): 20 seconds (when absolutely charged)
  • Velocity ​​up the 5% grade: velocity restrict on the freeway
  • Powertrain: 3 unbiased motors (up from 4 motors in entry-spec 2017)
    – two electrical motors for acceleration on the rear axle (with automated shutdown)
    – one electrical motor for freeway driving on the second axle (at all times on)
    – Rotors with carbon sleeves similar to Plaid
  • Quick charging: as much as 70% vary in half-hour
  • Gasoline financial savings (estimate): as much as $200,000 over 3 years
Tesla MI2023 VIN decoder

Beginning costs (at launch in 2017):

  • Anticipated base worth (300 mile vary) – $150,000
  • Anticipated base worth (500 mile vary) – $180,000
  • Base reservation – $20,000
  • Anticipated worth of the founder collection – $ 200,000
  • Founder Collection Reserve – $200,000
    * Costs are proven in USD. Worldwide costs will differ.

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