40170 tops 47460 at Perth on 1T04 2350 Inverness-Glasgow Queen Street for the run from Perth to Stirling on 27/07/1983. At Stirling the train would split with 47460 heading its portion to Edinburgh Waverley, whilst 40170 continued to Glasgow Queen Street. The reason for the class 40 being utilised was due to the diagrammed class 47 having received a broken windsceen earlier in the day and Eastfield were unable to repair it in time.