The A1AA1A 68000 was a series of mixed-traffic diesel locomotives introduced in 1963 which were suitable for traffic on both main and secondary lines. Due to their heavy steam heating boiler, they weighed 105 tonnes and needed six axles in total. The bogies had a A1A wheel arrangement, what meant two powered axles on the ends and a central unpowered carrying axle. The suspension of the central axles could be switched to change the load on the driven axles between 18 and 20 tonnes.
In total, 81 were built in the 68000 number range with a Sulzer 12 LDA 24 and 29 in the 68500 number range were built with a SACM AGO DSHR 2700, both delivering 1,985 kW or 2,700 hp. With later refurbishments, some locomotives got the other engine type, effectively rebuilding them into the other class.
With the introduction of more powerful four and six axle locomotives in the mid-seventies, they were no longer used for passenger service. Some even got their steam heating boilers removed and replaced by ballast weights. After only being used for freight and work trains for a long time, they were shortly re-introduced into passenger service in the nineties due to a shortage of rolling stock, where they were used double-headed. Today, nearly have been withdrawn.
