SP GP20 page: 1965 system renumbering
1965 Renumbering:
In late 1965, the SP began a program to renumber the majority of its locomotive fleet into a consolodated system without regard for reporting mark. However, the SSW units did retain their identity, but the numbers were assigned within the overall scheme.
SP:
| 1965 numbers | Orig. numbers | notes |
| SP 4050-4073 | SP 7200-7223 | |
| SP 4074-4083 | SP 7224-7233 | |
| SP 4084-4087 | SP 7200-7223 | orig. EMD 5625-5628 demonstrators |
SSW:
| 1965 numbers | Orig. numbers | notes |
| SSW 4030-4039 | SSW 800-809 | |
| SSW 4040-4049 | SSW 810-819 |