As heavier trains on the Pennsylvania Railroad became a reality, the Pennsylvania Railroad needed a heavier steam locomotive to handle a freight train on the system, so the L2s was demoted to smaller services and eventually retirement, when engines like the J1 and in later years, diesels replaced them too.
PRR S1 | PRR L1s | PRR K4s | PRR E6 | PRR GG1 | PRR MP54 | PRR E44 | PRR DD1 | PRR D6 | PRR 3750 | PRR 1361 |