
All Conrail C-420's came from Lehigh & Hudson River and took series 2072 - 2077. The units lacked dynamic brakes, rode on AAR Type-B trucks, and had full classification lights. They were based in Bethlehem, PA, and Warwick, NY.
The 2,400hp C-424 replaced the RS-27 between 1963-1967. 15 Conrail units came from Erie Lackawanna, 10 from the Reading Company, and 1 from Penn Central (a former-PRR unit). Series CR 2474-2499
The 2,500hp C-425 had the same main generator of GE's U25B. Conrail was the largest C-425 owner, with 41 from Penn Central (31 former Pennsylvania and 10 former New Haven). Series CR 2416-2459 then renumbered to 5060-5088.
Becauase ALCo built only sixteen 3,000hp C-430's, Conrail became the largest owner of them. Two came from the Reading Company and ten from Penn Central (former-NYC units). Series CR 2048-2059.
Originally designed to replace the RSD-15, the 2,800hp C-628 was built between 1963-1967. Conrail inherited 15 from Penn Central (former PRR units) and 17 from Lehigh Valley, 9 of which were former Monon units. Series CR 6721-6752.
ALCo built the 3,000hp C-630 from 1965-1967. Only 77 were built. Conrail inherited fifteen C-630's from Penn Central (former-PRR units) and 12 from the Reading Company. Series CR 6753-6779.
Built in 1967-1968, the C-636 was the most powerful, single-engine locomotive that ALCo built. Nearly visually identical to the C-630, the C-636 rode on new Hi-Ad (high-adhesion) trucks. ALCo built only 34 units, 15 of which Conrail inherited from Penn Central. Series CR 6781-6794.