BART is delaying the rollout of hundreds of its new cars due to mechanical issues.
They planned to have 775 new cars in service by 2022. But it will now be the spring of 2023 before those cars come online.
Apparently BART expected its "D" cars, the ones where the operator sits, to run 6,000 hours before any sort of equipment failure that causes a delay of more than 5 minutes. However, those issues are now popping up at just 1,000 hours of service.