Although the Pioneer III design was advanced for its time, operating headaches and a ready stream of available GG1 locomotive-hauled coaches spelled a premature end to the Pioneer III coaches in long-distance passenger service. In 1963, as part of an effort to improve commuter rail service in the Philadelphia area, the PRR contracted with the Budd Company to build a more advanced version of the Pioneer III design. Using the Pioneer III as a model, the new "Silverliner", as the stainless steel MU coaches were called, differed greatly from the Pioneers. They all had fabricated trucks with air springs and disc brakes, more powerful traction motors, two rows of ceiling lights, improved air-conditioning, the use of an automatic MU coupler that automatically made electrical connections in addition to the usual AAR "knuckle" design and a sleeker T-shaped (Faiveley) pantograph in place of the diamond-shaped pantograph. 38 Silverliner cars (201–219, 251–269) were built for the PRR, with 17 nearly identical cars (9001–9017) for the Reading Company tacked onto the same order.