Document:

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                                                                 EXHIBIT 10.20.1

                                                                  EXECUTION COPY

                                 AMENDMENT NO. 1

                            dated as of June 20, 2003

                                      among

                      AMERICREDIT MTN RECEIVABLES TRUST II,

                                  as Purchaser

                            AMERICREDIT MTN CORP. II

                                    as Seller

                      AMERICREDIT FINANCIAL SERVICES, INC.,

                                    as Seller

                               JPMORGAN CHASE BANK

                  (formerly known as THE CHASE MANHATTAN BANK)

                               as Collateral Agent

                                       and

                           MBIA INSURANCE CORPORATION

                                 as Note Insurer

                    to MASTER RECEIVABLES PURCHASE AGREEMENT

                            dated as of June 12, 2001

<PAGE>

        THIS AMENDMENT NO. 1, dated as of June 20, 2003 to the MASTER
RECEIVABLES PURCHASE AGREEMENT, dated as of June 12, 2001 (this "Amendment") is
among AMERICREDIT MTN RECEIVABLES TRUST II (the "Purchaser"), AMERICREDIT MTN
CORP. II (the "Seller"), and AMERICREDIT FINANCIAL SERVICES, INC., ("the
"Seller"), and as consented to by JPMORGAN CHASE BANK (formerly known as The
Chase Manhattan Bank), as the Collateral Agent, and MBIA INSURANCE CORPORATION,
as the Note Insurer.

        WHEREAS, the Purchaser, the Collateral Agent and the Sellers entered
into a Master Receivables Purchase Agreement dated as of June 12, 2001 relating
to the $750,000,000 AmeriCredit MTN Receivables Trust II Note;

        WHEREAS, Section 7.4(b) of the Master Receivables Purchase Agreement
permits amendment of the Master Receivables Purchase Agreement by the Sellers
and the Purchaser with the consent of the Collateral Agent and of the Note
Insurer (the "Parties"), in accordance with the Security Agreement;

        WHEREAS, the Parties wish to amend the Master Receivables Purchase
Agreement as provided herein.

        NOW, THEREFORE, for good and valuable consideration, the receipt and
adequacy of which are hereby acknowledged, the Parties agree that the Master
Receivables Purchase Agreement is hereby amended effective as of the date hereof
as follows:

        Section 1. Amendment to Section 1.2 (Specific Terms)

        Section 1.2 is amended by adding the following definition:

        "Related Security" means with respect to any Receivable:

                (i) all of the Sellers' interest in the Financed Vehicles
        (including repossessed vehicles) or in any document or writing
        evidencing any security interest in any Financed Vehicle and all of the
        Sellers' interest in all rights to payment under all insurance contracts
        with respect to a Financed Vehicle, including, without limitation, any
        monies collected from whatever source in connection with any default of
        an Obligor with respect to a Financed Vehicle and any proceeds from
        claims or refunds of premiums on any physical damage, lender's single
        interest, credit life, disability and hospitalization insurance policies
        covering Financed Vehicles or Obligors;

                (ii) all of the Sellers' interest in all other security
        interests or liens and property subject thereto from time to time, if
        any, purporting to secure payment of such Receivable, whether pursuant
        to the Contract related thereto or otherwise, together with all
        financing statements signed by an Obligor and security agreements
        describing any collateral securing such Contract;

                (iii) all of the Sellers' interest in all guaranties,
        indemnities, warranties, insurance (and proceeds and premium refunds
        thereof) and other agreements or arrangements of

<PAGE>

        whatever character from time to time supporting or securing payment of
        such Receivable, whether pursuant to the Contract related to such
        Receivable or otherwise;

                (iv) all of the Sellers' interest in all rights to payment under
        all service contracts and other contracts and agreements associated with
        such Receivables and all of the Sellers' interest in all recourse rights
        against the dealers (excluding any rights in any dealer reserve);

                (v) all of the Sellers' interest in all Records, documents and
        writings evidencing or related to such Receivables or the Contracts;

                (vi) all of the Sellers' interest, rights and remedies under
        this Agreement; and

                (vii) all Proceeds of the foregoing.

        Section 2. Separate Counterparts. This Amendment may be executed by the
parties hereto 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 3. 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 4. Binding Effect; Ratification.

                (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 Master Receivables Purchase Agreement,
        and (ii) each reference in any Transaction Document (as defined in the
        Insurance Agreement) to the Master Receivables Purchase Agreement shall
        mean and be a reference to the Master Receivables Purchase Agreement as
        amended hereby.

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

                            [Signature Pages Follow]

<PAGE>

        IN WITNESS WHEREOF, the parties have executed this Amendment No. 1 as of
the date set forth on the first page hereof.

                                           AMERICREDIT MTN RECEIVABLES TRUST II

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

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

                                           AMERICREDIT FINANCIAL SERVICES, INC.,
                                           as Seller

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

                                           AMERICREDIT MTN CORP. II, as Seller

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

As consented to by:

JP MORGAN CHASE BANK, as
  Collateral Agent

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

MBIA INSURANCE CORPORATION,
 as Note Insurer

By:
   ------------------------
    Name:
    Title:<PAGE>

                                                                 EXHIBIT 10.22.5

                                 AMENDMENT NO. 4

                            dated as of April 1, 2003

                                      among

                      AMERICREDIT MTN RECEIVABLES TRUST II,

                                   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 June 12, 2001

<PAGE>

        THIS AMENDMENT NO. 4 TO THE SECURITY AGREEMENT, dated as of April 1,
2003 (this "Amendment") is among AMERICREDIT MTN RECEIVABLES TRUST II (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").

        WHEREAS, the Debtor, AFS, MBIA, Meridian, AmeriCredit MTN Corp. II and
JPMorgan Chase Bank (successor to Chase Manhattan Bank) entered into a Security
Agreement dated as of June 12, 2001 relating to the $750,000,000 AmeriCredit MTN
Receivables Trust II Note;

        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 and Amendment No. 3, dated as of February 28, 2003 among the Parties;

        WHEREAS, the Insurer is the Controlling Party under the Transaction
Documents;

        WHEREAS, the Parties wish to amend the Security Agreement as provided
herein.

        NOW, THEREFORE, for good and valuable consideration, the receipt and
adequacy of which are hereby acknowledged, 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 "Credit Score Based Reserve Percentage" in Section
        1.1 is amended and restated, in its entirety, as follows:

        "Credit Score Based Reserve Percentage" means, with respect to the
        Amortization Period, the applicable percentage set forth in the number
        clauses (i) through (v) below:

                        (i) 13% if the Weighted Average AmeriCredit Score of all
                Eligible Receivables as of the commencement of the Amortization
                Period, after taking into account all Facility Activity on such
                date is greater than or equal to 235.00; or

                        (ii) 14% if the Weighted Average AmeriCredit Score of
                all Eligible Receivables as of the commencement of the
                Amortization Period, after taking into account all Facility
                Activity on such date is greater than or equal to 234 but less
                than 235; or

<PAGE>

                        (iii) 15% if the Weighted Average AmeriCredit Score of
                all Eligible Receivables as of the commencement of the
                Amortization Period, after taking into account all Facility
                Activity on such date is greater than or equal to 232 but less
                than 234; or

                        (iv) 16% if the Weighted Average AmeriCredit Score of
                all Eligible Receivables as of the commencement of the
                Amortization Period, after taking into account all Facility
                Activity on such date is greater than or equal to 230 but less
                than 232; or

                        (v) 17% if the Weighted Average AmeriCredit Score of all
                Eligible Receivables as of the commencement of the Amortization
                Period, after taking into account all Facility Activity on such
                date is greater than or equal to is less than 230.

        (b) The definition of "Initial Reserve Percentage" in Section 1.1 is
        amended and restated, in its entirety, as follows:

        "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
                235.00; 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
                234.00 but less than 235.00; 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 234.00; or

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

<PAGE>

                        (iv) 9%, if

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

        (c) The definition of "Premium Side Letter" in Section 1.1 is amended
        and restated, in its entirety, as follows:

                "Premium Side Letter" means the letter of agreement dated June
        11, 2001 between AmeriCredit and the Note Insurer, as amended, modified
        or otherwise supplemented from time to time.

        (d) The definition of "Revolving Period Reserve Percentage" in Section
        1.1 is amended and restated, in its entirety, as follows:

                "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 (iv) 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 235.00; 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 234.00 but less than
                        235.00; 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 232.00 but less than
                        234.00; or

<PAGE>

                        (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 232.00; or

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

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

        Section 6.1(nn) is amended and restated, in its entirety, as follows:

                (nn) The portion of AmeriCredit's total committed and in good
        standing warehouse facilities that is insured by the Note Insurer
        exceeds 40%.

        Section 4. Separate Counterpart. This Amendment may be executed by the
parties hereto 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 5. 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 6. Binding Effect; Ratification.

                (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.

                            [Signature Pages Follow]

<PAGE>

        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 II

                                           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 Insurer

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

                                           MERIDIAN FUNDING COMPANY, LLC,
                                            as Purchaser

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

Signature Page for Amendment No. 4
to the Security Agreement (MTN II)

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