GATX (GATX) 10-K 2011 FY Annual report

Exhibit 32

GATX CORPORATION AND SUBSIDIARIES

CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350

CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Annual Report of GATX Corporation (the “Company”) on Form 10-K for the period ending December 31, 2011, as filed with the Securities and Exchange Commission on the date hereof (the “Report”), each of the undersigned officers of the Company, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:

1) The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

2) The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

/s/    BRIAN A. KENNEY	/s/    ROBERT C. LYONS
Brian A. Kenney Chairman, President and Chief Executive Officer	Robert C. Lyons Senior Vice President and Chief Financial Officer

February 24, 2012

This certification accompanies the Report pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 and shall not be deemed filed by GATX Corporation for purposes of Section 18 of the Securities Exchange Act of 1934, as amended.

A signed original of this written statement required by Section 906 has been provided to GATX Corporation and will be retained by GATX Corporation and furnished to the Securities and Exchange Commission or its staff upon request.

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