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                                                                    Exhibit 10.3

                                 AMENDMENT NO. 8

                          dated as of November 1, 2003

                                      among

                     AMERICREDIT MTN RECEIVABLES TRUST III,
                                   as Debtor,

                      AMERICREDIT FINANCIAL SERVICES, INC.,
                          Individually and as Servicer,

                           MBIA INSURANCE CORPORATION,
                                 as Note Insurer

                                       and

                         MERIDIAN FUNDING COMPANY, LLC,
                                  as Purchaser

                                       to

                               SECURITY AGREEMENT

                          dated as of February 25, 2002

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          AMENDMENT NO. 8, dated as of November 1, 2003 (the "Amendment"), among
AMERICREDIT MTN RECEIVABLES TRUST III (the "Debtor"), AMERICREDIT FINANCIAL
SERVICES, INC., individually and in its capacity as Servicer ("AFS"), MBIA
INSURANCE CORPORATION, as Note Insurer ("MBIA"), and MERIDIAN FUNDING COMPANY,
LLC, as Purchaser ("Meridian"), to the Security Agreement dated as of February
25, 2002 (the "Security Agreement"), among the Debtor, AFS, AmeriCredit MTN
Corp. III and JPMorgan Chase Bank, as Collateral Agent and as Securities
Intermediary.

          WHEREAS, Section 9.2(b) of the Security Agreement permits amendment of
the Security Agreement by the Debtor, AFS, MBIA and Meridian (the "Parties")
upon the terms and conditions specified therein;

          WHEREAS, the Security Agreement has previously been amended by
Amendment No. 1, dated as of December 1, 2002; Amendment No. 2, dated as of
February 1, 2003; Amendment No. 3, dated as of February 28, 2003; Amendment No.
4, dated as of April 1, 2003; Amendment No. 5, dated as of June 20, 2003;
Amendment No. 6, dated as of August 18, 2003; and Amendment No. 7, dated as of
August 1, 2003;

          WHEREAS, the Parties wish to amend the Security Agreement.

          NOW, THEREFORE, the Parties agree that the Security Agreement is
hereby amended effective as of the date hereof as follows:

     Section 1. Definitions. Each term used but not defined herein shall have
the meaning assigned to such term in the Security Agreement.

     Section 2. Amendments to Section 1.1 (Certain Defined Terms).

          (a) The definition of "Defaulted Receivable" is deleted in its
entirety and is replaced with the following:

               "Defaulted Receivable" means a Receivable with respect to which
          (i) all or any portion in excess of 10% of a Scheduled Payment is more
          than ninety (90) days past due, (ii) the Servicer has repossessed the
          related Financed Vehicle (and any applicable redemption period has
          expired), or (iii) such Receivable is in default and the Servicer has
          charged-off such Receivable in accordance with the Credit and
          Collection Policy or otherwise has determined in good faith that
          payments thereunder are not likely to be resumed.

          (b) The definition of "Delinquent Receivable" is deleted in its
entirety and is replaced with the following:

               "Delinquent Receivable" means a Receivable with respect to which
          10% or more of a Scheduled Payment is more than sixty (60) days past
          due (excluding (i) Receivables with respect to which the Servicer has
          repossessed the related Financed Vehicle and (ii) Receivables which
          have become Liquidated Receivables).

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          (c) The definition of "Initial Reserve Percentage" is amended by
     deleting clause (iv) in its entirety and replacing it with the following:

               (iv) 9%, if the most-recently calculated Portfolio Net Loss Ratio
          is greater than or equal to 8.00% but less than 8.50%.

               (v) 10%, if the most-recently calculated Portfolio Net Loss Ratio
          is greater than or equal to 8.50%.

          (d) The definition of "Revolving Period Reserve Percentage" is amended
     by deleting clause (iv) in its entirety and replacing it with the
     following:

               (iv) 11%, if either

                    (a)  the Weighted Average AmeriCredit Score of all Eligible
                         Receivables as of such date of determination, after
                         taking into account all Facility Activity on such date
                         is less than 232.00; or

                    (b)  the most-recently calculated Portfolio Net Loss Ratio
                         is greater than or equal to 8.00% but less than 8.50%.

               (v) 12%, if the most-recently calculated Portfolio Net Loss Ratio
          is greater than or equal to 8.50%.

          (e) The following definition of "Commission" is inserted in
appropriate alphabetical order:

               "Commission" means the United States Securities and Exchange
          Commission.

     Section 3. Amendment to Section 5.4 (Affirmative Covenants of the
Servicer). The following clause (j) is added immediately following clause (i) of
Section 5.4:

          (j) (i) No later than December 15, 2003, (ii) between March 1 and
     March 30 of each calendar year, beginning in calendar year 2004, and (iii)
     between September 1 and September 30 of each calendar year, beginning in
     calendar year 2004, the Servicer shall provide the Note Insurer with (A) a
     written confirmation from S&P that the rating on the Note issued by the
     Debtor, without regard to the Note Policy, is at least "BBB" as of the date
     of such confirmation and (B) a written confirmation from Moody's that the
     rating on the Note issued by the Debtor, without regard to the Note Policy,
     is at least "Baa2" as of the date of such confirmation; provided, that if
     either or both of S&P and Moody's is unable to confirm its aforementioned
     "BBB" or "Baa2" rating, respectively, during the related time period, then
     the Servicer shall have the right to provide additional credit enhancement
     to cause either or both of S&P and Moody's, as necessary, to provide the
     related confirmation and the Servicer shall be deemed not to have breached
     this covenant if it has provided the Note Insurer with the related

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     confirmation by (i) December 30, 2003, (ii) the related April 15 or (iii)
     the related October 15, as appropriate.

     Section 4. Amendments to Section 6.1 (Termination and Amortization Events).

          (a) Clause (p) of Section 6.1 is deleted in its entirety and is
replaced with the following:

          (p) the Portfolio Net Loss Ratio for any Determination Date shall
     exceed (i) 9.00% or (ii) if the credit enhancement associated with any
     public asset-backed securitization sponsored by AmeriCredit that closes on
     or after November 1, 2003 decreases to an amount below 18%, 8.50%; or

          (b) Clause (x) of Section 6.1 is deleted in its entirety and replaced
with the following:

          (x) (I) the Tangible Net Worth of AmeriCredit Corp. shall be less than
     the sum of (a) $1,700,000,000 and (b) 75% of the cumulative positive net
     income (without deduction for negative net income) of AmeriCredit Corp. for
     each fiscal quarter having been completed since June 30, 2003, as reported
     in each annual report on Form 10-K and periodic report on Form 10-Q filed
     by AmeriCredit Corp. with the Commission less (c) the amount of any stock
     repurchase; (II) the Tangible Net Worth of AmeriCredit Corp. shall be less
     than the sum of (a) $1,600,000,000 and (b) 75% of the cumulative positive
     net income (without deduction for negative net income) of AmeriCredit Corp.
     for each fiscal quarter having been completed since June 30, 2003, as
     reported in each annual report on Form 10-K and periodic report on Form
     10-Q filed by AmeriCredit Corp. with the Commission; or (III) upon the
     completion of any stock repurchase by AmeriCredit Corp., AmeriCredit Corp.
     shall fail to maintain corporate cash deposits of less than $200,000,000;
     or

          (c) Clause (mm) of Section 6.1 is deleted in its entirety and replaced
with the following:

          (mm) the GAAP Portfolio Net Loss Ratio for any Determination Date
     shall exceed (i) 9.00% or (ii) if the credit enhancement associated with
     any public asset-backed securitization sponsored by AmeriCredit that closes
     on or after November 1, 2003 decreases to an amount below 18%, 8.50%; or

     Section 5. Separate Counterparts. This Amendment may be executed by the
Parties in separate counterparts, each of which when so executed and delivered
shall be an original, but all such counterparts shall together constitute but
one and the same instrument.

     Section 6. Governing Law. THIS AMENDMENT SHALL BE GOVERNED BY AND CONSTRUED
IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO ITS
CONFLICTS OF LAW PROVISIONS.

     Section 7. Binding Effect; Ratification of Security Agreement.

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          (a) This Amendment shall become effective as of the date first set
forth above, when counterparts hereof shall have been executed and delivered by
the parties hereto, and thereafter shall be binding on the parties hereto and
their respective successors and assigns.

          (b) On and after the execution and delivery hereof, (i) this Amendment
shall be a part of the Security Agreement and (ii) each reference in any
Transaction Document (as defined in the Insurance Agreement) to the Security
Agreement shall mean and be a reference to the Security Agreement as amended
hereby.

          (c) Except as expressly amended hereby, all provisions of the Security
Agreement shall remain in full force and effect and are hereby ratified and
confirmed by the parties hereto.

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          IN WITNESS WHEREOF, the parties hereto have executed this Amendment as
of the date set forth on the first page hereof.

                             AMERICREDIT MTN RECEIVABLES TRUST III

                             By: DEUTSCHE BANK TRUST COMPANY
                                 DELAWARE, not in its individual capacity but
                                 solely as Owner Trustee on behalf of the Issuer


                             By:
                                 -------------------------------------
                                 Name:
                                 Title:


                             AMERICREDIT FINANCIAL SERVICES, INC.,
                                Individually and as Servicer,


                             By:
                                 -------------------------------------
                                 Name:
                                 Title:


                             MBIA INSURANCE CORPORATION,
                                as Note Insurer,


                             By
                                --------------------------------------
                                Name:
                                Title:


                             MERIDIAN FUNDING COMPANY, LLC,
                                as Purchaser


                             By
                                --------------------------------------
                                Name:
                                Title: