According to Haas Formula 1 team principal Guenther Steiner, the unexpected high brake temperatures were responsible for the rear suspension failure that resulted in Kevin Magnussen's significant crash during the Formula 1 Mexico Grand Prix.
On lap 32 of the race, the Danish driver experienced a suspected left rear track rod failure, causing him to go off the track when the car was under load in the fast right-hander at Turn 8. Although Magnussen managed to exit the car unaided, the crash caused damage to the barriers and prompted a red flag. He was examined at the medical center but was declared fit and returned to the paddock.
Brake temperatures in Mexico are typically at their limit, and in Magnussen's case, they became excessively high as he defended his position against Logan Sargeant and adjusted the brake bias toward the rear. Sargeant overtook him shortly before the crash, and Magnussen was then advised by his engineer to bring the brake temperatures under control.
Following the crash, television footage showed a brake fire starting around the left rear of the wrecked Haas car.
During the red-flag period, the team inspected the sister car of Nico Hulkenberg but found no signs of any issues, allowing Hulkenberg to continue the race.
Steiner explained, "It was a heat issue that caused a suspension failure, a heat from the brakes. Kevin was defending, and it tipped over. It was solely due to the high temperatures here, and we need to manage it better. Nico's car was unaffected."
Despite the extensive damage and the loss of an entire set of the recent upgrade package, Steiner reassured that the team has enough spare parts for the remainder of the season. He mentioned, "We're fine. It's not ideal, but it's manageable. It's always better to have spare parts toward the end of the season, as you can't obtain any more parts at this point, even if you wanted them."
Just before the crash, Magnussen had alerted the team, saying, "the rear left has completely gone here," implying that he might have received a warning that something was amiss. He also mentioned, "I'm feeling okay. The suspension gave up. The rear left, in particular, lost a lot of grip a couple of laps before the incident. I suddenly lost a lot of grip on that side, and then it failed."