The trolleybus service to Conisbrough was withdrawn on 1 January 1928, to allow alterations to the overhead wiring to be made. In just two months, the wiring was ready for testing and they borrowed a Doncaster double-deck vehicle to allow this to take place. The routes to Manvers and Conisbrough were now connected, and services ran from Manvers to Conisbrough Low, and from Mexborough to Conisbrough High. The next section to be converted was the route southwards to the Woodman Inn at Swinton, which opened on 11 November 1928, following a Ministry of Transport inspection two days earlier. Services were re-routed, with trolleybuses from Manvers now running to Conisbrough High, and those from Conisbrough Low running to Swinton. That left the trams running between Swinton and Rotherham, and they were finally withdrawn on 9 March 1929, with trolleybuses running through to Rottherham from the following day. There was a branch along Kilnhurst Road, near the Rawmarsh depot, that allowed short working to be operated to Ryecroft. The Company bought a fleet of new vehicles from Garretts to operate the services, and changed its name to the Mexborough & Swinton Traction Co in 1929, reflecting the fact that they no longer ran trams. They added a turning circle at Conisbrough High in February 1931, to replace a longer loop around a crescent, and opened a branch along Adwick Road, Mexborough on 28 June 1931. This was intended to be the start of a northern extension, but no further progress was made with this. The wires were diverted along a new section of wider and straighter road to the north of Rawmarsh on 28 February 1932, and the final addition to the network saw the Kilnhurst Road branch turned into a loop on 15 October 1934, which was used by services from Rotherham, but operated by vehicles owned by the Company.