A Leaked Tesla Report Shows the Cybertruck Had Basic Design Flaws

Tesla did not respond to requests for comment.

The internal dynamics and NVH—noise, vibration and harshness—report leaked to Handelsblatt contains test results measuring the performance of the alpha version of the Cybertruck against projections made using computer-aided design (CAD) simulations, and against internal benchmarks. In summary, it presents a picture of a prototype vehicle that’s leaky, noisy, and has poor handling and braking.

“It’s an alpha-stage vehicle, so it’s not surprising that it’s some way off its targets,” says Andy Palmer, the former COO of Nissan and CEO of Aston Martin Lagonda, who has more than 40 years of experience in the automotive industry. Palmer says he’s surprised at the frankness of the report. “You’d be giving the engineers that wrote this stuff a good bollocking. You don’t normally write this down.”

The report says that the alpha version of the Cybertruck had to be hand-sealed, but that “there are a number of areas that we do not have a clear path to sealing” in a production version of the vehicle. This is an issue not just for keeping the weather out, but for noise in the cabin. Data in the report shows that the alpha version was significantly noisier than engineers had projected based on their designs, and that testers had identified 21 potential noise leaks in the body of the vehicle.

Tesla cars have a history of leaking, and the report hints that the Cybertruck’s unusual design may have complicated engineers’ attempts to properly seal it. “​​Body manufacturing and paint shop processes have struggled to seal bodies for optimal NVH performance in the past, and the Cybertruck design presents new challenges,” the report says.

Handling was also a concern for the alpha Cybertruck. The report noted a number of issues, including “excessive mid-speed abruptness and chop,” “high head-toss accelerations,” and “structural shake.” It said that the truck experienced “excessive lateral jerk during low-speed maneuvering” and that it needed to address problems with steering refinement and body roll. The EV’s strafe mode, a feature that allows the wheels to turn to allow the car to “crab walk” sideways had “only basic functionality.”

Braking performance was one of the worst areas of the report. Tesla’s engineers were aiming for a score of 7, or “fair,” on the Society of Automotive Engineers rating scale, but the alpha version achieved only a 4, or “poor” rating. According to the report, in January 2022, the Cybertruck’s brake pedal pressure pad was still under design, and so the alpha experienced “excessive pedal travel and inconsistent stop,” and “excessive pitch during friction braking,” braking during turning issues, as well as power braking instability.

“The brake performance seems serious. I’m surprised they’re not further forward,” Palmer says, after being apprised of the content of the report. Normally, the chassis, including the braking system, is the first thing that engineers work on, ahead of the body and other systems. “So to be only on prototype parts at this stage is quite late.”