UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 __________________________________________ FORM 10-Q __________________________________________ x QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2019 or ¨ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Commission File Number: 1-2328 GATX Corporation (Exact name of registrant as specified in its charter) New York 36 ...