For obvious reasons, the Maybach-engined diesel-hydraulic locomotives of various continental railways are some of the most popular among British enthusiasts. The most powerful production fleet of these were a fleet of 32 machines procured by Spain in the late 1960s.
Looking to British eyes like BR ‘Warships’, the RENFE class 4000s were in fact closer to being a pair of ‘Hymeks’ within one bodyshell – having two MD870 engines with Mekydro K184 transmissions, giving a 4,000hp locomotive. Unlike their German counterparts, which had long since dispensed with vacuum braking, the 4000s were dual braked.
RENFE placed the order not with any one manufacturer but in fact with LEU, the Lokomotiv Export Union – a collaboration between Krupp, Krauss-Maffei and Babcock & Wilcox. The first ten locos – 4001 to 4010 – were built by Krauss-Maffei in München in 1966. The others – 4011 to 4032 – were built by Babcock & Wilcox in Bilbao between 1967 and 1969. The fleet were reclassified as class 340 in the 1970s and renumbered accordingly.
The entire fleet were out of service by the late 1980s. Just two locos survive – 340 020 in the Museo del Ferrocarril de Madrid and 340 026 with AZAFT in Zaragoza. The latter is undergoing restoration; it is sure to be a very popular machine once complete.