Under the designation E40AC, originally E40 AG-V1, Siemens offered a six-axle electric freight locomotive for use on cape-gauge lines with high permitted axle loads. With the first customer being Queensland Railways, its electric part was based on the QR class 3700 that had been rebuilt from the classes 3100 and 3200 by Siemens. The E40AC also had the wheel arrangement B-B-B, but power had been increased to 4,000 kW or 5,364 hp. 

Starting in 2006, 45 were built at Munich-Allach and designated QR class 3800. The next orders came from Pacific National with 23 and BHP Mitsubishi Alliance with 13. After PN had increased its total orders to 42, total number increased to 100. In service, up to three locomotives at a time were used to haul coal trains of up to 12,500 tons. In these cases, one locomotive is being used as mid-train DPU.