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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

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        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

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        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]

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        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: