In the early years trains of the second and third series of electric locomotive class 420 in the color pure orange / Kieselgrau (contrary to original plans, the proposed paint carmine / kieselgrau was not used) were used in Frankfurt, although occasionally lent to 1990 due to lack of vehicles also from Munich blue white 420s were used, for example, the opening of the trunk line extension to Frankfurt South. The cars of the 2nd construction series were delivered completely to the S-Bahn Munich until the beginning of the 2000s. Due to the ever-increasing vehicle demand at that time were between 1980 and 2004 at irregular intervals all railcars of the third and fourth series and numerous cars of the fifth and sixth series from the S-Bahn Stuttgart delivered to Frankfurt.