This sound effect can be found on the Series 8000 Science Fiction Sound Effects Library, which was made by Sound Ideas. It is essentially a variant of SKYWALKER, TRAIN - POLAR EXPRESS CHUGGING, but specifically the one used as the footstep sound for the Iron Giant in the film of the same name, along with the other pieces of media it's heard in. Links: https://soundideas.sourceaudio.com/track/7597751 https://soundeffects.fandom.com/wiki/Sound_Ideas,_FOOTSTEPS_-_GIANT_ROBOTIC_FOOTSTEPS,_COULD_ALSO_USE_AS_AN_INDUSTRIAL_PRESS,_SCI_FI#Audio_Samples