The IIIs, designated class 322 from 1911, was designed for heavy passenger service. It was a four-cylinder compound 2-6-2 that used the same boiler and cylinder dimensions as the In (class 203) 4-4-2 express locomotive. The 2-6-2 wheel arrangement was chosen in order to get three driving axles while retaining the trailing axle that carried the large firebox. MÁVAG built 40 in 1908 and 1909. As the requirements included a maximum axle load of 14 tonnes, the chassis was designed in a way that some weight of the driving axles could be transferred to the leading and trailing axles. 

However, the maximum axle load in this configuration was still 14,365 kg. In the other configuration, the first driving axle carried 15,645 kg. In the effect, these 40 locomotives were only operated on two lines which lay between Budapest, today's Slovakia and Lower Austria. On the level, they could haul 350 tonnes with their top speed of 90 km/h. On 1.5 percent inclines, it was 265 tonnes with 60 km/h. With the introduction of the class 301 Pacifics, the class 322 was increasingly used in freight service.

After World War I, 13 came to Czechoslovakia and eight to Romania. The CFR had withdrawn them by 1937, but the ČSD started a rebuilding program to decrease the maintenance effort of the four-cylinder drive with crank axle. In 1929 and 1930, twelve of their locomotives, now called class 365.2, were converted to superheated two-cylinder simples at their Rutka works. These were used until 1960, but the MÁV even used their unrebuilt locomotives one year longer.