Just as SEPTA began phasing in Silverliner V rail cars that had been repaired by manufacturer Hyundai Rotem, 18 rail cars were pulled back out for further repairs.

SEPTA announced on Monday that a “minor design modification” will be made to the foot that supports the new equalizer beam. On Saturday, after a joint inspection of the cars that had been returned to service, Hyundai Rotum made design changes to address the issue that “resulted in minimal, occasional contact between old and new components,” SEPTA said.

"SEPTA is committed to making sure the repair process is done correctly to ensure a long-lasting life," said SEPTA General Manager Jeffrey D. Knueppel. "This is why we are conducting thorough tests and inspections, such as the one on Saturday that revealed this problem."

"All parties involved are working around the clock to restore the Silverliner V fleet to service in a timely fashion," Knueppel added. "We sincerely regret the continued inconvenience to our customers."

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SEPTA said it expects the modified cars to be back in service later this week and Hyundai Rotem is still expected to return enough rail cars to allow for normal weekday Regional Rail schedules by SEPTA's preferred date of Oct. 3 or Oct. 10 at the latest.

The overall time-frame for completing repairs and returning all Silverliner Vs to service remains early-to-mid November.

For the latest service updates related to the Silverliner V repairs, visit the Interim Weekday Service Information page on the SEPTA website.