<PAGE>

                      SECURITIES AND EXCHANGE COMMISSION


                           WASHINGTON, D.C. 20549


                                  FORM 8-K


                               CURRENT REPORT


                    PURSUANT TO SECTION 13 OR 15(d) OF THE
                       SECURITIES EXCHANGE ACT OF 1934

                       Date of Report: August 14, 2000

               AmeriCredit Automobile Receivables Trust 1999-D
           (Exact Name of Registrant as specified in its charter)


      United States                    333-36365                88-0441485
      -------------                    ---------                ----------
(State or Other Jurisdiction    (Commission File Number)     (I.R.S. Employer
    of Incorporation)                                     Identification Number)



                            c/o AmeriCredit Financial
                                  Services, Inc.
                           Attention:  Daniel E. Berce
                          801 Cherry Street, Suite 3900
                              Fort Worth, TX  76102
                              (Address of Principal
                                 Executive Office)

                                  (817) 302-7000
                            Registrant's phone number

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Item 5.       Other Events

       Information relating to distributions to Noteholders for the July 2000
       Collection Period of the Registrant in respect of the Class A-1 Asset
       Backed Notes, Class A-2 Asset Backed Notes, Class A-3 Asset Backed Notes,
       and Class A-4 Asset Backed Notes (collectively, the "Notes") issued by
       the Registrant.  The performance of the Receivables held by the
       Registrant, together with certain other information relating to the
       Notes, is contained in the Preliminary Servicer's Certificate and the
       Servicer's Certificate for the referenced Collection Period. Both of
       which Certificates are provided to Noteholders pursuant to the Sale and
       Servicing Agreement dated as of October 13, 1999 between the Registrant,
       AFS Funding Corp., as Seller, AmeriCredit Financial Services, Inc., as
       Servicer, and Bank One, N.A., as Backup Servicer and Trust Collateral
       Agent (the "Agreement").

Item 7.       Financial Statements, Exhibits

<TABLE>
<CAPTION>

    Exhibit No.          Exhibit
    -----------          -------
    <S>                  <C>
       99.1              Preliminary Servicer's Certificate and Servicer's
                         Certificate for the July 2000 Collection Period
                         relating to the Notes issued by the Registrant
                         pursuant to the Agreement.
</TABLE>



<PAGE>

                                  SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


AmeriCredit Automobile Receivables Trust 1999-D

By: AmeriCredit Financial Services, Inc., as Servicer




/s/   Daniel E. Berce
      Daniel E. Berce
      Vice Chairman and
      Chief Financial Officer


August 14, 2000



<PAGE>

                                 EXHIBIT INDEX

<TABLE>
<CAPTION>

Exhibit
-------
<S>                          <C>
  99.1                       Preliminary Servicer's Certificate and Servicer's
                             Certificate for the July 2000 Collection Period
                             relating to the Notes issued by the Registrant.
</TABLE>