Filed: 30 Mar 20, 4:19pm

Exhibit 31.2
Certification of Principal Financial Officer
I, Thomas A. Ellman, certify that:
1. I have reviewed this Amendment No. 1 to the Annual Report on Form 10-K of GATX Corporation (the "Company"); and
2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report.
Thomas A. Ellman
Executive Vice President and Chief Financial Officer
March 30, 2020