Thrifty as the Swabians are, in 1906 the Royal Württemberg State Railways decided to purchase a proven Prussian design. Up till then none of the Southern German railways had dared to take such a step. The T 9 was in service in Prussia under the designation T 9.3. The first unit was placed into service in 1901. The boiler of this locomotive was high compared with others. The length of the flue was somewhat less than that of the preceding type, the T 9.2. As there was more space for piping in the boiler, the T 9.3 had the same heating surface. The first coupled wheel set and the pilot truck wheel set were combined in a Krauss-Helmholtz frame. The coupled axle could slide 27 mm / 1-1/16", the pilot truck axle 20 mm / 25/32" to either side. The first coupled wheel set thereby took over some of the steering work from the pilot truck wheel set. The Prussian State Railways placed no fewer than 2,052 units in service. In addition, there were 133 locomotives for the Alsace-Lorraine State Railways, as well as 23 locomotives for other railroads, including 10 for Württemberg. The last German Federal Railroad locomotive was retired in 1964; the last German State Railroad locomotive was taken out of service in the early 1970s.