General Motors Financial (ACF) 10-K 2004 FY Annual report

EXHIBIT 32.1

CERTIFICATION OF PERIODIC REPORT PURSUANT TO SECTION 906

OF SARBANES-OXLEY ACT OF 2002

I, the undersigned Clifton H. Morris, Jr., Chairman of the Board and Chief Executive Officer of AmeriCredit Corp. (the “Company”), do hereby certify, pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, 18 U.S.C. Section 1350, that:

(1) The Annual Report on Form 10-K of the Company for the fiscal year ended June 30, 2004 (the “Report”) fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 (15 U.S.C. 78m or 78o(d)); and

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

Dated: September 13, 2004

/s/ Clifton H. Morris, Jr.

Clifton H. Morris, Jr.

Chairman of the Board and

Chief Executive Officer

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CERTIFICATION OF PERIODIC REPORT PURSUANT TO SECTION 906

OF SARBANES-OXLEY ACT OF 2002

I, the undersigned Daniel E. Berce, President of AmeriCredit Corp. (the “Company”), do hereby certify, pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, 18 U.S.C. Section 1350, that:

(1) The Annual Report on Form 10-K of the Company for the fiscal year ended June 30, 2004 (the “Report”) fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 (15 U.S.C. 78m or 78o(d)); and

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

Dated: September 13, 2004

/s/ Daniel E. Berce

Daniel E. Berce

President

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CERTIFICATION OF PERIODIC REPORT PURSUANT TO SECTION 906

OF SARBANES-OXLEY ACT OF 2002

I, the undersigned Preston A. Miller, Executive Vice President, Chief Financial Officer and Treasurer of AmeriCredit Corp. (the “Company”), do hereby certify, pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, 18 U.S.C. Section 1350, that:

(1) The Annual Report on Form 10-K of the Company for the fiscal year ended June 30, 2004 (the “Report”) fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 (15 U.S.C. 78m or 78o(d)); and

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

Dated: September 13, 2004

/s/ Preston A. Miller

Preston A. Miller

Executive Vice President, Chief

Financial Officer and Treasurer

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