The South Australian Railways 400-class Beyer-Garratt locomotives were purchased for the heavy Broken Hill (Cockburn) to Port Pirie ore trains, replacing the 300-class Australian Standard Garratts which had been performing this duty as a stopgap since 1952.  Beyer Peacock & Co copied the proven East African Railways "60-class" design, with construction subcontracted to Societe Franco-Belge, France due to high post-war sales volumes exceeding Beyer Peacock's workshop capacity.  Ten locomotives were supplied, numbered 400 - 409.  The 400-class class were oil fired and became very successful in SAR service.

Preserved locomotive 409 was Societe Franco-Belge builder's number F2982 of 1953 and also carries Beyer Peacock & Co builder's number 7631.  All ten members of the South Australian Railways "400-class" arrived on the ship "Belnor" and were placed in service between 1953 and 1954, with 409 commissioned last in February 1954.

The class were based at Peterborough depot and were the prime freight locomotives on the SAR narrow gauge until the arrival of 830-class diesel electric locomotives from 1963.  Together with members of the T-class, the 400-class Beyer Garratts enjoyed a final swansong of main-line duty in 1969 - 1970 while the diesel fleet was being converted to standard gauge preceding cutover to the new Port Pirie - Broken Hill railway.  After standard gauge cutover the 400-class were quickly withdrawn and sold for scrap, excepting 402 and 409 which were saved for preservation.

409 was displayed from November 1970 at the open-air Mile End Railway Museum, Adelaide.  All Mile End exhibits transferred to the new National Railway Museum, Port Adelaide in 1988 and 409 is now a prime exhibit at Port Adelaide, displayed in the main exhibit hall in unlined black livery.