In the late 1980s, New South Wales considered discontinuing passenger services across the country due to the high cost of operating old railcars and locomotive-hauled trains. As a solution, the Xplorer and Endeavour diesel-hydraulic railcars were developed as cost-effective alternatives. Both are mechanically nearly identical and were built by ABB at Dandenong, Victoria. Each car has a 514 hp Cummins KTA-19R powering both axles of one bogie via a Voith T311r transmission. For air conditioning and lighting, each car has a 181 hp Cummins LT10R(G) with an alternator.

Seven three-car Xplorer sets were built between 1993 and 1995 for longer-distance services. They can be configured with two to four cars. Between 1994 and 1996, 15 two-car Endeavour sets were built for shorter distances which have a modified interior layout. One of the Endeavour sets was later modified into an Xplorer. Both types were refurbished starting in 2007 and 2009.