In 1946, Estrada de Ferro Santos-Jundiaí, administered by the federal government, assumed the operation of the railway, which is the current lines 7-Ruby and 10-Turquoise.

In mid-1937, Estrada de Ferro Sorocabana built a branch, connecting Mairinque to Santos, with the objective to take down the monopoly that São Paulo Railway had in the link between the plateau and the seaside.

In 1971, all of the railways controlled by the state government of São Paulo were unified to become Ferrovia Paulista S/A (FEPASA), amongst them the Estrada de Ferro Sorocabana.

[2][3] At the same time, the suburban trains operated by RFFSA (Lines Santos-Jundiaí, Tronco Mogi and Variante Poá) received modest investments.

[4] Even with the transfer of the suburban lines from RFFSA to the recently created CBTU, the precariousness of the urban trains administered by the federal government reached a peak in 1987 with the Itaquera rail crash.

On 30 April 1987, the state government and the Ministry of Transports signed an intention protocol for the transfer of CBTU East Line-Mogi to the Metro administration.