"São Paulo" underwent a refit in New York, beginning on 7 August 1918 and completing on 7 January 1920. Many of its crewmen were assigned to American warships during this time for training. It received Sperry fire control equipment and Bausch and Lomb range-finders for the two superfiring turrets fore and aft. A vertical armor bulkhead was fitted inside all six main turrets, and the secondary battery of casemate guns was reduced from twenty-two to four guns. A few modern AA guns were fitted as well: two 3"/50 caliber guns from Bethlehem Steel were added on the aft superstructure, 37 mm guns were added near each turret, and 3 pounders were removed from the top of turrets.