In 2001, there was an interesting rumour floating about that the 1502s were being regauged for standard gauge traffic using ex-49 class bogies. It turns out this rumour was actually quite true.

The 423 class are being built from surplus 1502 class locomotives at Redbank Workshops. Modifications include the fitting of a Maxi-Cab, Airconditioning, Dual Control Stands, Visibility lights, and a lowered nose. It seems that no modifications are being made to the power plan though (ie. turbos aren’t being fitted, nor is the generators being replaced by alternators)

The class will be painted in the current NRR Livery and will wear the Interail logo.

So far the count is at 6 members of the class, 42301 – 42304 in Interail livery and 42305 & 42306 in QRNational Livery

The 422 class, purchased by QR National/Interail from Northern Rivers Railroad, were originally built in 1969 for SRA (and then Freightcorp) by Clyde Engineering at Granville. The locos are of a full body dual cab design and have use the EMD16-645E power plant (which effectively makes them an updated version of the 421s). The 422s have operated across Australia after a number were purchased by Australian Southern Railroad (ASR) in the period 2000-2005. Refurbished and renumbered to the 22 class, most notably were 2201-2204 which were used on the construction of the Alice Springs to Darwin line. In 2006, QRNational owns 18 members of the class, including 42202 and 42206 (ex-Interail); along with the 16 members of the 22 class (some renumbered, some are not).