The ALCO C-643DH, also known as the Century 643DH, was a twin-engine diesel-hydraulic locomotive, the first diesel-hydraulic road switcher built in the United States. It had a C-C wheel arrangement and generated . Only three were built, all for Southern Pacific Railroad in 1964 (#9018–#9020). The Alco C-643DHs joined 21 Krauss-Maffei ML-4000 diesel-hydraulics already on the Southern Pacific's roster. They spent most of their service lives in the flat San Joaquin Valley in California.
Dissatisfaction over the poor performance of diesel-hydraulic locomotives, as well as their use of foreign-made components (the hydraulic transmission was of German Voith design), eventually led Southern Pacific to sell the 3 C-643DHs for scrap in 1973. None of the 3 examples built survived into preservation.
Original owners
{| class="wikitable"
! Railroad !! Quantity !! Road numbers !! Notes
|-
|Southern Pacific Railroad ||style="text-align:center;" |3 || 9018–9020 || renumbered 9150–9152
|-
|}
See also
- List of ALCO diesel locomotives
- ALCO Century 855
References
External links
- Alco Six-Axle Centuries Roster
- Southern Pacific DH-643