 The number of axles was increased from 4 to 6 to cope with the low maximum axle load on Yugoslavian tracks.The locomotives remained in working order until 1991 and are now stored at a railway museum in a suburb of Belgrade.A fourth example of the ML 2200 C'C' was built at Krauss-Maffei's own expense, awaiting a buyer, but the Yugoslavian state railways made no further purchases.