SEPTA on Thursday began the long process of replacing 231 aging Silverliner IV train cars, even as it waits for the last of its new Silverliner V cars.

SEPTA officials met with representatives of 12 car manufacturers and other companies in an "expression of interest" session Thursday.

Among the manufacturers expressing interest in bidding on a contract for the new cars was Hyundai Rotem Corp., which built the new Silverliner V cars but fell two years behind schedule amid production and labor problems.

The Silverliner IV cars, which are the bulk of the Regional Rail fleet, are nearly 40 years old, about the age that their forerunners were back in 2006, when SEPTA ordered the new cars to replace them.

The Silverliner IVs were built by General Electric Co. from 1974 to 1976. GE is no longer in the train-building business.

In addition to Hyundai Rotem, the companies that attended Thursday's session included Alstom, Kawasaki, Nippon Sharyo USA, Sumitomo, Sojitz, Bombardier, Mitsubishi, STV, Carmen Group, Faiveley Transport, and Wabtec.

The new Silverliner VIs are likely to cost about $3 million each, and SEPTA said it did not have enough money to buy them now.

SEPTA relies on state and federal funds for its capital budget, funding for vehicles and big construction projects. Both Harrisburg and Washington have been cutting transit spending.

Although ridership is at a 23-year high, SEPTA's capital budget is at a 15-year low, at $303 million.