They were regular visitors to the London area, often running on London Midland Region and Western Region tracks. In the early half of the 1970s, milk trains for the Southern Region were a staple for the class as far as Acton Yard, requiring diesel power from Clapham Junction through Kensington and onto the Western Region mainline (Class 52 or occasionally Class 47 were used for the major haul west of Acton to and from Cornwall and Devon). This would usually produce two trains per weekday and often two different examples of the class. These milk trips were of note as they often included Diesel Brake Tenders (DBT - basically heavy, weighted bogie wagons with vacuum brakes) to assist with available braking effort. Neither were they immune to locomotive failures and Old Oak Common TMD on the Western Region had been home to a failure from Acton Yard on more than one occasion.