Document:

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                                                                   EXHIBIT 10.12

                                     WAIVER

                                February 28, 2003

To the Parties on the
 Attached Exhibit A

     Re: AmeriCredit MTN Receivables Trust III

     Reference is made to that certain Security Agreement dated as of February
25, 2002, (the "Security Agreement") among the AmeriCredit MTN Receivables Trust
III, as Debtor (the "Debtor"), AmeriCredit Financial Services, Inc.,
individually and as servicer (the "Servicer"), AmeriCredit MTN Corp. III,
individually, and The Chase Manhattan Bank, as Collateral Agent and as
Securities Intermediary (the "Collateral Agent) and the Servicing and Custodian
Agreement (the "Servicing and Custodian Agreement") dated as of February 25,
2002, by and among the Servicer, the Debtor and the Collateral Agent.
Capitalized terms used herein but not defined herein shall have the meanings
ascribed to such terms in the Security Agreement or the Servicing and Custodian
Agreement, as the case may be.

     Section 6.1(r) of the Security Agreement provides that a Termination and
Amortization Event shall occur if the Cumulative Net Loss Ratio exceeds the
amount specified for the related Determination Date in Exhibit M to the Security
Agreement. MBIA Insurance Corporation ("MBIA") is aware that for the
Determination Date occurring in March 2003, the Cumulative Net Loss Ratio
exceeds the amount specified in Exhibit M to the Security Agreement, therefore a
Termination and Amortization Event pursuant to Section 6.1(r) of the Security
Agreement has occurred (the "March Termination and Amortization Event"). Section
4.1(e) of the Servicing and Custodian Agreement provides that a Servicer
Termination Event shall occur upon the occurrence of a Termination and
Amortization Event listed in Section 6.1 of the Security Agreement. As a result
of the March Termination and Amortization Event, a Servicer Termination Event
has occurred for March 2003 (the "March Servicer Termination Agreement").
Section 5.01 (c) and (h) of the Insurance Agreement provide that an Event of
Default under the Insurance Agreement shall occur upon the occurrence of a
Termination and Amortization Event or a Servicer Termination Event. As a result
of the March Termination and Amortization Event and the March Servicer
Termination Agreement, an Event of Default under the Insurance Agreement has
occurred for March 2003 (the "March Insurance Agreement Event of Default").

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     Pursuant to Section 6.2 of the Security Agreement, Section 4.5 of the
Servicing and Custodian Agreement, and Section 5.03 of the Insurance Agreement,
you are hereby notified that MBIA waives the March Termination and Amortization
Event, the March Servicer Termination Event and the March Insurance Agreement
Event of Default for all purposes under the Transaction Documents.

     Notwithstanding the foregoing or anything to the contrary herein, in the
Security Agreement, the Servicing and Custodian Agreement or the Transaction
Documents or in any other document in connection therewith, MBIA intends this
waiver to be limited to the event described herein and shall not constitute, and
shall not be construed to be, a waiver of any future Termination and
Amortization Event, Servicer Termination Event, the Event of Default under the
Insurance Agreement or any other event. This waiver is wholly without prejudice
to, and, other than as specifically set forth herein, shall not constitute a
waiver in any respect of, the rights of MBIA in respect of its rights under the
Transaction Documents and shall not in any way alter or affect the rights,
duties or obligations of MBIA under the Transaction Documents.

                                              MBIA INSURANCE CORPORATION

                                              By /s/ Rosemary Kelley
                                                --------------------------------

Signature Page to February 28, 2003
Waiver (MTN III)

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                                    EXHIBIT A

AmeriCredit Financial Services Inc.
801 Cherry Street
Suite 3900
Fort Worth, Texas 76102
Telecopy: (817) 302-7942

AmeriCredit MTN Corp. III
801 Cherry Street
Suite 4000
Fort Worth, Texas 76102
Attention: Treasury Department
Telecopy: (817) 302-7082

AmeriCredit MTN Receivables Trust III
C/o Deutsche Bank Trust Company Delaware,
formerly known as Bankers Trust (Delaware)
E.A. Delle Donne Corporate Center
Montgomery Building
1011 Centre Road, Suite 200
Wilmington, DE 19805
Telecopy: (302) 636-3222

JPMorgan Chase Bank, formerly
known as The Chase Manhattan Bank
450 West 33rd Street, 14th Floor
New York, NY 10001
Attention:  AmeriCredit MTN Receivables Trust III
Telecopy: (212) 946-8302

                                        3<PAGE>

                                                                   EXHIBIT 10.13

                                                                  EXECUTION COPY

                                 AMENDMENT NO. 3

                          dated as of February 28, 2003

                                      among

                     AMERICREDIT MTN RECEIVABLES TRUST III,

                                   as Debtor,

                      AMERICREDIT FINANCIAL SERVICES, INC.,

                          Individually and as Servicer,

                           MBIA INSURANCE CORPORATION,

                                   as Insurer

                                       and

                         MERIDIAN FUNDING COMPANY, LLC,

                                  as Purchaser

                              to SECURITY AGREEMENT

                          dated as of February 25, 2002

<PAGE>

        AMENDMENT NO. 3, dated as of February 28, 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 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.
and the Chase Manhattan Bank (predecessor to JPMorgan Chase Bank), as Collateral
Agent and 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, and Amendment No. 2, dated as of February
1, 2003, among the Parties;

        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 herein but not defined herein
shall have the meaning assigned to such term in the Security Agreement.

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

        (a) The definition of "Amortization Period Reserve Percentage" in
Section 1,1 is deleted in its entirety and replaced with the following:

        "Amortization Period Reserve Percentage" means,

                (x)     with respect to any date of determination which occurs
                        after the commencement of the Amortization Period and
                        prior to the seventh (7th) Remittance Date during the
                        Amortization Period:

                        (i)     13.0% if the Portfolio Net Loss Ratio calculated
                                as of the most recent Determination Date is less
                                than 7.00%.

                        (ii)    14.0%, if the Portfolio Net Loss Ratio
                                calculated as of the most recent Determination
                                Date is greater than or equal to 7.00% but less
                                than 7.50%.

                        (iii)   15.0%, if the Portfolio Net Loss Ratio
                                calculated as of the most recent Determination
                                Date is greater than or equal to 7.50% but less
                                than 8.00%.

                                        2

<PAGE>

                        (iv)    16.0%, if the Portfolio Net Loss Ratio
                                calculated as of the most recent Determination
                                Date is greater than or equal to 8.00% but less
                                than 8.50%.

                        (v)     17.0%, if the Portfolio Net Loss Ratio
                                calculated as of the most recent Determination
                                Date is greater than or equal to 8.50%; and

                (y)     with respect to any date of determination occurring on
                        and after the seventh (7th) Remittance Date during the
                        Amortization Period, the applicable percentage set forth
                        in the numbered clauses (i) through (v) in paragraph (x)
                        above calculated with respect to the (6th) Remittance
                        Date.

        (b) The definition of "Initial Reserve Percentage" in Section 1.1 is
deleted in its entirety and replaced with the following:

        "Initial Reserve Percentage" means, with respect to any Delivery Date:

                (i) 6%, if both

                        (a) the Weighted Average AmeriCredit Score of all
                        Eligible Receivables (including the Receivables to be
                        delivered on such Receivables Delivery Date) is greater
                        than or equal to 227.00; and

                        (b) the most-recently calculated Portfolio Net Loss
                        Ratio is less than 7.00%

                (ii) 7%, if either

                        (a) the Weighted Average AmeriCredit Score of all
                        Eligible Receivables (including the Receivables to be
                        delivered on such Receivables Delivery Date) is greater
                        than or equal to 226.00 but less than 227.00; or

                        (b) the most-recently calculated Portfolio Net Loss
                        Ratio is greater than or equal to 7.00% but less than
                        7.50%.

                (iii) 8%, if either

                        (a) the Weighted Average AmeriCredit Score of all
                        Eligible Receivables (including the Receivables to be
                        delivered on such Receivables Delivery Date) is less
                        than 226.00; or

                        (b) the most-recently calculated Portfolio Net Loss
                        Ratio is greater than or equal to 7.50% but less than
                        8.00%.

                (iv) 9%, if

                                        3

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

        (c) The definition of "Net Spread Deficiency" in Section 1.1 is deleted
in its entirety and replaced with the following:

        "Net Spread Deficiency" means, as of any Borrowing Base Determination
        Date, the positive difference, if any, of (i) the sum of (A) 8.75% plus
        (B) the Servicing Fee, expressed as a percentage of the Net Receivables
        Balance plus (C) the lesser of (x) one-month LIBOR plus (I) from the
        Closing Date up to and including the thirty-sixth (36th) Remittance
        Date, 0.7500% and (II) after the thirty-sixth (36th) Remittance Date,
        1.8750% and (y) the weighted average strike price under the Hedging
        Arrangements then in effect, minus (ii) the weighted average APR of all
        Eligible Receivables then held as Collateral.

        (d) The definition of "Reserve Account Required Amount" in Section 1.1
is deleted in its entirety and replaced with the following:

        "Reserve Account Required Amount" means,

                        (x) as of any Borrowing Base Determination Date during
                        the Revolving Period, the product of (i) the applicable
                        Revolving Period Reserve Percentage and (ii) the Net
                        Receivables Balance as of such Borrowing Base
                        Determination Date; and

                        (y) as of any date of determination during the
                        Amortization Period, the lesser of:

                                (i) the greatest of:

                                        (A) 6.0% of the Aggregate Outstanding
                                        Balance of all Receivables as of the
                                        commencement of the Amortization Period;

                                        (B) the product of (I) the applicable
                                        Amortization Period Reserve Percentage
                                        and (II) the Aggregate Outstanding
                                        Balance of all Receivables as of such
                                        date of determination; and

                                        (C) the product of (I) the Credit Score
                                        Based Reserve Percentage applicable to
                                        the Amortization Period and (II) the
                                        Aggregate Outstanding Balance of all
                                        Receivables as of such date of
                                        determination; and

                                (ii) the Net Investment as of such date of
                                determination

                                        4

<PAGE>

        (e) The definition of "Revolving Period Reserve Percentage" in Section
1.1 is deleted in its entirety and replace with the following:

        "Revolving Period Reserve Percentage" means, with respect to any
        Borrowing Base Determination Date during the Revolving Period, the sum
        of (x) if, and only if, the Weighted Average Age of the Eligible
        Receivables then exceeds 180.00 days, 3%, plus (y) the applicable
        percentage set forth in the numbered clauses (i) through (v) below:

                (i) 8%, if both

                        (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 greater than or equal to 227.00; and

                        (b) the most-recently calculated Portfolio Net Loss
                        Ratio is less than 7.00%.

                (ii) 9%, 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 greater than or equal to 226.00 but less than
                        227.00; or

                        (b) the most-recently calculated Portfolio Net Loss
                        Ratio is greater than or equal to 7.00% but less than
                        7.50%.

                (iii) 10%, 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 greater than or equal to 224.00 but less than
                        226.00; or

                        (b) the most-recently calculated Portfolio Net Loss
                        Ratio is greater than or equal to 7.50% but less than
                        8.00%.

                (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 224.00; or

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

        (f) A new definition of "GAAP Portfolio Net Loss Ratio" is added to
        Section 1.1 in alphabetical order as follows:

                                        5

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        "GAAP Portfolio Net Loss Ratio" means, as of any date of determination,
        the ratio (expressed as a percentage), computed by dividing "A" by "B",
        and then multiplying the result by "C" where:

                        "A" is equal to the net charge-offs (as defined in
                        AmeriCredit Corp.'s 10-Q and 10-K SEC filings) for the
                        Servicing Portfolio that have occurred during the six
                        Settlement Periods immediately preceding such date
                        divided by (ii) the average Aggregate Outstanding
                        Balance of the Servicing Portfolio during such six-month
                        period;

                        "B" is equal to the actual number of days in such
                        six-month period; and

                        "C" is equal to the actual number of days in the
                        Servicer's fiscal year in which the most recently ended
                        Settlement Period occurred.

        Section 3. Amendment to Section 6.1 (Termination and Amortization
        Events).

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

                (p)     the Portfolio Net Loss Ratio (i) for any Determination
                Date occurring prior to March 1, 2003 shall exceed 8.00%, (ii)
                for any Determination Date occurring subsequent to March 1, 2003
                and prior to August 1, 2003 shall exceed 9.00%, or (iii) for any
                Determination Date occurring subsequent to August 1, 2003 shall
                exceed 8.00%; or

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

                (q)     the Portfolio Repossession Ratio, on a 3-month rolling
                average basis, (i) as measured on or prior to the February 2003
                Determination Date, is greater than 1.5%, (ii) as measured on
                the Determination Dates occurring in the months March 2003
                through July 2003 is greater than 2.00%, or (iii) as measured on
                or subsequent to the August 2003 Determination Date is greater
                than 1.5%; or

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

                (z)     the ratio of AmeriCredit Corp.'s EBITDA (plus any loss
                provision minus net charge-offs and excluding in the calculation
                a one-time, non-cash impairment charge to the credit enhancement
                assets related to the present value effect of the expected delay
                in receiving cash distributions from FSA insured securitization
                trusts) for the financial quarter ended December 31, 2002 to its
                Interest Expense for the financial quarter ended December 31,
                2002 shall be less than 1.5x. The ratio of AmeriCredit Corp.'s
                EBITDA (plus any charge or charges related to restructuring,
                plus any loss provision minus net charge-offs) for the financial
                quarter ended March 31, 2003 to its Interest Expense for the
                financial quarter ended

                                        6

<PAGE>

                March 31, 2003 shall be less than 1.8x. The average of the
                ratios of AmeriCredit Corp.'s EBITDA to Interest Expense for the
                two most recent financial quarters ended June 30, 2003 shall be
                less than 1.0x. The average of the ratios of AmeriCredit Corp.'s
                EBITDA to Interest Expense for the two most recent financial
                quarters ended September 30, 2003 or December 31, 2003 shall be
                less than 1.1x. The average of the ratios of AmeriCredit Corp.'s
                EBITDA to Interest Expense for the two most recent financial
                quarters ended March 31, 2004 and any two consecutive financial
                quarters thereafter shall be less than 1.2x; or

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

                (ll) a Servicer Termination Event occurs; or

        (e) A new Section 6.1(mm) is added as follows:

                (mm) the GAAP Portfolio Net Loss Ratio for any Determination
                Date exceeds 8.00%; or

        (f) A new Section 6.1(nn) is added as follows:

                (nn) Excluding MBIA's MTN transactions, AmeriCredit fails to
                maintain $1.75 billion in committed and in good standing
                warehouse facilities.

                   [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK
                             SIGNATURE PAGE FOLLOWS]

                                        7

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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

                                                                ATTORNEY-IN-FACT
                                By: /s/ Louis Bodi
                                   ---------------------------------------------
                                   Name:    LOUIS BODI
                                   Title:   VICE PRESIDENT

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

                                By: /s/ Beth Sorensen
                                   ---------------------------------------------
                                   Name:    Beth Sorensen
                                   Title:   Senior Vice President, Finance

                                MBIA INSURANCE CORPORATION,
                                 as Insurer,

                                By: /s/ Rosemary Kelley
                                   ---------------------------------------------
                                   Name:    Rosemary Kelley
                                   Title:   Director

                                MERIDIAN FUNDING COMPANY, LLC,
                                 as Purchaser

                                By: /s/ Bernard J. Angelo
                                   ---------------------------------------------
                                   Name:    Bernard J. Angelo
                                   Title:   Vice President

Signature Page for Amendment No. 3
to the Security Agreement (MTN III)

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