General Motors is recalling around 66 electric delivery vans made by its BrightDrop subsidiary after the front drive units in at least two of them caught fire late last year.

The automaker says it’s still investigating the root cause of the fires, but believes a manufacturing defect may have caused the drive pinion to pierce the drive unit casing, creating an oil leak that could catch fire during heavy use. GM says in paperwork filed with the National Highway Traffic Safety Administration (NHTSA) that it believes the defect was limited to its larger EV600 vehicles built between November 24, 2021 and May 24, 2022.

Companies including FedEx and Walmart have taken delivery of the EV600. The recall doesn’t affect BrightDrop’s smaller EV400 vans. GM shipped 497 BrightDrop vans in total in 2023.

The recall comes just a few months after GM re-absorbed BrightDrop in an attempt to streamline its electric commercial vehicle efforts . BrightDrop initially launched in 2021 when GM spun it out of its Global Innovation organization.

“The safety of our products is the highest priority for the entire GM team, and we’re working to quickly remedy this matter for our customers,” the company said in a statement to TechCrunch.

GM received a report of a fire in the front drive unit of a BrightDrop EV600 on December 7, and another one on December 13, according to the paperwork filed with NHTSA. The company opened an investigation into the fires on December 22 and decided to conduct a recall on January 4. Both affected vehicles were owned by an undisclosed GM fleet customer.

This is the third recall for BrightDrop vehicles. The EV600 was previously recalled in late 2022 after the company discovered a problem with the water seal on the van’s high-voltage battery pack. It faced another recall in October when GM discovered an issue with one of the van’s airbags.

GM recalls dozens of electric BrightDrop vans after two reported fires | TechCrunch