US Escalates Probe Into 1.1 Million GM Vehicles Linked To 745 Brake Incidents And 21 Crashes

• A GM brake investigation now covers more than 1.1 million vehicles.
• Regulators logged 745 incidents, including 21 crashes and five injuries.
• The same eBoost system links Cadillac, Chevy, GMC, Honda, and Acura.

The National Highway Traffic Safety Administration (NHTSA) has stepped up its investigation into brake issues in more than 1.1 million GM vehicles in the United States. However, despite the investigation being ongoing for more than two years, a recall has yet to be announced.

The NHTSA’s Office of Defects Investigation began a Preliminary Evaluation in April 2024 to probe issues after receiving complaints about a loss of brake assist in 2023 Cadillac Lyriq models.

Read: Cadillac Lyriq EV Under Investigation Over Brake Failures

GM’s own investigations blamed the failures on spindle fractures, but noted vehicles could still be brought to a stop and that the ABS, stability control, and traction control would remain functional. After that, these functions would be lost, multiple warning lights would be enabled, and vehicle speed would be capped at 43 mph (70 km/h).

Reports of the loss of brake assist have continued over the past two years, and according to the ODI, some describe symptoms that are inconsistent with GM’s description of a spindle failure. They report an immediate loss of brake assist functionality, rather than after the vehicle has come to a complete stop. In light of these reports, the NHTSA has escalated the investigation to an Engineering Analysis.

Several GM Models Impacted

It’s not just Cadillac Lyriq models that are being looked into. A slew of vehicles are equipped with the same eBoost system, including 2023-2026 Cadillac Lyriq, Chevrolet Colorado, and GMC Canyon models, 2024-2026 Buick Enclave, Envision, Chevrolet Blazer EV, Chevrolet Equinox EV, Traverse, Cruise Original, and GMC Acadia models, as well as the 2025-2026 Cadillac Celestiq and Optiq. The 2024-2024 Acura ZDX and 2025-2026 Honda Prologue, built alongside GM, are also included in the investigation.

In total, the probe is looking into an estimated 1,164,820 vehicles. The agency is aware of 745 total incidents related to brake system issues, including 21 crashes/fires and five incidents causing injury.