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 421s were initially employed on various duties in NSW including RIC Works trains, Soybean and Flyash trains and also the Ritz Rail. However with the collapse of Ritz Rail and the Murwillumbah branch closing, the 421s have found themselves back in the Hunter Valley working Coal Trains out of Newstan and Duralie. Along with providing assistance on QRNational’s MB/BM7 trains. It seems these old workhorses have a few years left in them. Fortunately the livery the locos wear will be retained (the NRR livery is one of the most popular in Australia).

The Interail 421s are based out of Casino, NSW.