MASTER RECEIVABLES PURCHASE AGREEMENT

Exhibit 10.3

MASTER RECEIVABLES

PURCHASE AGREEMENT

among

AMERICREDIT MTN RECEIVABLES TRUST IV,

as Purchaser,

AMERICREDIT FINANCIAL SERVICES, INC.,

individually and as Seller,

AMERICREDIT MTN CORP. IV,

as Seller,

and

JPMORGAN CHASE BANK,

as Collateral Agent

dated as of

October 1, 2004

TABLE OF CONTENTS

EXHIBITS

Exhibit A — Form of Supplement

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MASTER RECEIVABLES PURCHASE AGREEMENT

THIS MASTER RECEIVABLES PURCHASE AGREEMENT, dated as of October 1, 2004, executed among AmeriCredit MTN Receivables Trust IV, a Delaware statutory trust, as purchaser (“ Purchaser ”), JPMorgan Chase Bank, as collateral agent (the “ Collateral Agent ”), AmeriCredit MTN Corp. IV, a Delaware corporation, as seller (“ AMC ”) and AmeriCredit Financial Services, Inc., a Delaware corporation, as seller (“ AFS ” and together with AMC, the “ Sellers ”).

W I T N E S S E T H :

WHEREAS, Purchaser has agreed to purchase from time to time from the Sellers, and the Sellers, pursuant to this Agreement, have agreed to transfer from time to time to the Purchaser the Receivables and Other Conveyed Property.

NOW, THEREFORE, in consideration of the premises and the mutual agreements hereinafter contained, and for other good and valuable consideration, the receipt of which is acknowledged, Purchaser and the Sellers, intending to be legally bound, hereby agree as follows:

ARTICLE I.

DEFINITIONS

SECTION 1.1 General . The specific terms defined in this Article include the plural as well as the singular. The words “herein,” “hereof” and “hereunder” and other words of similar import refer to this Agreement as a whole and not to any particular Article, Section or other subdivision, and Article, Section, Schedule and Exhibit references, unless otherwise specified, refer to Articles and Sections of and Schedules and Exhibits to this Agreement. Capitalized terms used herein without definition shall have the respective meanings assigned to such terms in the Security Agreement (as defined herein) or the Servicing and Custodian Agreement (as defined herein).

SECTION 1.2 Specific Terms . Whenever used in this Agreement, the following words and phrases, unless the context otherwise requires, shall have the following meanings:

“ Agreement ” shall mean this Master Receivables Purchase Agreement and all amendments hereof and supplements hereto.

“ Collateral Agent ” means JPMorgan Chase Bank, as collateral agent and any successor collateral agent appointed and acting pursuant to the Security Agreement.

“ Other Conveyed Property ” means all property conveyed by the Sellers to the Purchaser pursuant to this Agreement and the Supplement other than the Receivables.

“ Purchase Amount ” means, with respect to a Receivables the Outstanding Balance of such Receivable and all accrued and unpaid interest on such Receivables, after giving effect to the receipt of any funds collected (from whatever source on such Receivable).

“ Receivables ” means the Receivables (as defined in the Security Agreement) listed on the Schedules of Receivables attached to each Supplement.

“ Receivables Transfer Date ” means the date specified in the related Supplement as the date of contribution and/or sale of Receivables by the Sellers named therein to the Purchaser.

“ 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 form 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 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.

“ Relevant Cutoff Date ” means the date specified in the related Supplement, provided, however that such date shall be on or before the related Receivables Transfer Date.

“ Repurchase Event ” means the occurrence of a breach of any of Seller’s representations and warranties hereunder or under the Servicing and Custodian Agreement, or the breach of any Seller’s covenants set forth in Article IV.

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“ Sale Agreement ” means each “Sale Agreement” in substantially the form attached as Exhibit A to the Sale and Contribution Agreement, which is hereafter executed by AFS and AMC.

“ Sale and Contribution Agreement ” means the Sale and Contribution Agreement, dated as of the dated hereof, by and between AMC (as Purchaser) and AFS (as Seller).

“ Schedules of Receivables ” means the lists of Receivables sold and transferred pursuant to this Agreement and the Schedules which are attached to the Supplements as Schedules A and B thereto.

“ Security Agreement ” means the Security Agreement, dated as of the date hereof, by and among the Purchaser (as Debtor), AFS (in its individual capacity and as Servicer), AMC and the Collateral Agent.

“ Servicing and Custodian Agreement ” means the Servicing and Custodian Agreement, dated as of the date hereof, by and among AFS (as Servicer and as Custodian), the Trust and the Collateral Agent.

“ Supplement ” means each agreement by and among the Sellers and the Purchaser pursuant to which the Purchaser will acquire Receivables, substantially in the form of Exhibit A hereto.

SECTION 1.3 Usage of Terms . With respect to all terms used in this Agreement, the singular includes the plural and the plural the singular; words importing any gender include the other gender; references to “writing” include printing, typing, lithography, and other means of reproducing words in a visible form; references to agreements and other contractual instruments include all subsequent amendments thereto or changes therein entered into in accordance with their respective terms and not prohibited by this Agreement, the Servicing and Custodian Agreement, the Security Agreement or the Note Purchase Agreement; references to Persons include their permitted successors and assigns; and the terms “include” or “including” mean “include without limitation” or “including without limitation.”

SECTION 1.4 No Recourse . Without limiting the obligations of Sellers hereunder and except to the extent otherwise provided in the Transaction Documents, no recourse may be taken, directly or indirectly, under this Agreement or any certificate or other writing delivered in connection herewith or therewith, against any stockholder, officer or director, as such, of Sellers, or of any predecessor or successor of Sellers.

ARTICLE II.

CONVEYANCE OF THE RECEIVABLES

AND THE OTHER CONVEYED PROPERTY

SECTION 2.1 Conveyance of the Receivables and the Other Conveyed Property . By execution of this Agreement and subject to the terms and conditions of this Agreement and simultaneously with the execution and delivery of the related Supplement, the relevant Sellers shall sell and/or contribute, transfer and assign to the Purchaser (collectively, the

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“ Conveyance ”) without recourse (but without limitation of its obligations in this Agreement and the other Transaction Documents), and the Purchaser shall purchase or acquire as a contribution, all right, title and interest of such Sellers in and to:

ARTICLE III.

REPRESENTATIONS AND WARRANTIES

SECTION 3.1 Representations and Warranties of AFS . AFS makes the following representations and warranties as of the date hereof and as of each Receivables Transfer Date, as the case may be, on which Purchaser relies in purchasing the Receivables and the Other Conveyed Property. Such representations are made as of the execution and delivery of this Agreement and as of the execution and delivery by AFS of any Supplement, but shall survive the sale and/or contribution, transfer and assignment of the Receivables and the Other Conveyed Property hereunder and under any Supplement, and the grant of the security interest therein and the continuing lien therein by Purchaser to the Collateral Agent for the benefit of the Secured Parties under the Security Agreement. AFS and Purchaser agree that Purchaser will assign to Collateral Agent all Purchaser’s rights under this Agreement and that the Collateral Agent will thereafter be entitled to enforce this Agreement against AFS in the Collateral Agent’s own name on behalf of the Secured Parties.

(a) Eligible Receivables . Upon each Receivables Transfer Date, the Purchaser (i) will acquire each Receivable and the Other Conveyed Property free and clear of any Adverse Claim and (ii) will purchase each Receivable at fair market value. Each Receivable (including all Receivables sold hereunder by AFS or AMC) as of the date hereof and the Receivables Transfer Date is an Eligible Receivable.

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(b) Organization and Good Standing . AFS has been duly organized and is validly existing as a corporation in good standing under the laws of the State of Delaware, with power and authority to own its properties and to conduct its business as such properties are currently owned and such business is currently conducted, and had at all relevant times, and now has, power, authority and legal right to acquire, own and sell the Receivables and the Other Conveyed Property to be transferred to Purchaser.

(c) Due Qualification . AFS is duly qualified to do business as a foreign corporation in good standing, and has obtained all necessary licenses and approvals in all jurisdictions in which the ownership or lease of its property or the conduct of its business requires such qualification.

(d) Power and Authority . AFS has the power and authority to execute and deliver this Agreement and its Transaction Documents and to carry out its terms and their terms, respectively; AFS has full power and authority to sell and/or contribute, transfer and assign the Receivables and the Other Conveyed Property to be sold and/or contributed, transferred and assigned to and deposited with Purchaser hereunder and has duly authorized such sale or contribution, transfer and assignment to Purchaser by all necessary corporate action; and the execution, delivery and performance of this Agreement and AFS’s Transaction Documents have been duly authorized by AFS by all necessary corporate action.

(e) Valid Sale; Binding Obligations . This Agreement and AFS’s Transaction Documents have been duly executed and delivered, shall effect a valid sale or contribution, transfer and assignment of the Receivables and the Other Conveyed Property to the Purchaser, enforceable against AFS and creditors of and purchasers from AFS; and this Agreement and AFS’s Transaction Documents constitute legal, valid and binding obligations of AFS enforceable in accordance with their respective terms, except as enforceability may be limited by bankruptcy, insolvency, reorganization or other similar laws affecting the enforcement of creditors’ rights generally and by equitable limitations on the availability of specific remedies, regardless of whether such enforceability is considered in a proceeding in equity or at law.

(f) No Violation . The consummation of the transactions contemplated by this Agreement and the Transaction Documents, and the fulfillment of the terms of this Agreement and the Transaction Documents, shall not conflict with, result in any breach of any of the terms and provisions of, or constitute (with or without notice, lapse of time or both) a default under, the articles of incorporation or bylaws of AFS, or any indenture, agreement, mortgage, deed of trust or other instrument to which AFS is a party or by which it is bound, or result in the creation or imposition of any Lien upon any of its properties pursuant to the terms of any such indenture, agreement, mortgage, deed of trust or other instrument, other than this Agreement, the Security Agreement and the Note Purchase Agreement, or violate any law, order, rule or regulation applicable to AFS of any court or of any federal or state regulatory body, administrative agency or other

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governmental instrumentality having jurisdiction over AFS or any of its properties and do not require any action by or require the consent or approval of or the filing of any notice with any Official Body or any other Person.

(g) No Proceedings . There are no proceedings or investigations pending or, to AFS’s knowledge, threatened against AFS, before any court, regulatory body, administrative agency or other tribunal or governmental instrumentality having jurisdiction over AFS or its properties (i) asserting the invalidity of this Agreement or any of the Transaction Documents, (ii) seeking to prevent the issuance of the Note or the consummation of any of the transactions contemplated by this Agreement or any of the Transaction Documents, (iii) seeking any determination or ruling that might materially and adversely affect the performance by AFS of its obligations under, or the validity or enforceability of, this Agreement or any of the Transaction Documents or (iv) seeking to affect adversely the federal income tax or other federal, state or local tax attributes of, or seeking to impose any excise, franchise, transfer or similar tax upon, the transfer and acquisition of the Receivables and the Other Conveyed Property hereunder or under the Security Agreement.

(h) Chief Executive Office . The chief executive office of AFS is located at 801 Cherry Street, Fort Worth, Texas 76102.

(i) No Adverse Selection . No selection procedures adverse to the parties hereto or to the Secured Parties have been utilized in selecting the Receivables from all other similar Receivables owned by AFS and its Affiliates.

(j) Solvency . AFS shall not be insolvent on any Receivables Transfer Date and no Conveyance will cause AFS to become insolvent.

SECTION 3.2 [Reserved]

SECTION 3.3 Representations and Warranties of AMC . AMC makes the following representations and warranties as of the date hereof and as of each Receivables Transfer Date, as the case may be, on which Purchaser relies in purchasing the Receivables and the Other Conveyed Property. Such representations are made as of the execution and delivery of this Agreement and as of the execution and delivery by AMC of any Supplement, but shall survive the sale and/or contribution, transfer and assignment of the Receivables and the Other Conveyed Property hereunder and under any Supplement, and the sale and/or contribution, transfer and assignment thereof by Purchaser to the Collateral Agent under the Security Agreement. AMC and Purchaser agree that Purchaser will assign to Collateral Agent all Purchaser’s rights under this Agreement and that the Collateral Agent will thereafter be entitled to enforce this Agreement against AMC in the Collateral Agent’s own name on behalf of the Secured Parties.

(a) Eligible Receivables . Upon each Receivables Transfer Date, the Purchaser (i) will acquire each Receivable and the Other Conveyed Property free and clear of any Adverse Claim and (ii) will purchase each Receivable at fair market value. Each Receivable (including all Receivables sold hereunder by AFS or AMC) as of the date hereof and the Receivables Transfer Date is an Eligible Receivable.

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(b) Organization and Good Standing . AMC has been duly organized and is validly existing as a corporation in good standing under the laws of the State of Delaware, with power and authority to own its properties and to conduct its business as such properties are currently owned and such business is currently conducted, and had at all relevant times, and now has, power, authority and legal right to acquire, own and sell the Receivables and the Other Conveyed Property to be transferred to Purchaser.

(c) Power and Authority . AMC has the power and authority to execute and deliver this Agreement and its Transaction Documents and to carry out its terms and their terms, respectively; AMC has full power and authority to sell and/or contribute, transfer and assign the Receivables and the Other Conveyed Property to be sold and/or contributed, transferred and assigned to and deposited with Purchaser hereunder and has duly authorized such sale and/or contribution, transfer and assignment to Purchaser by all necessary corporate action; and the execution, delivery and performance of this Agreement and AMC’s Transaction Documents have been duly authorized by AMC by all necessary corporate action.

(d) Due Qualification . AMC is duly qualified to do business as a foreign corporation in good standing, and has obtained all necessary licenses and approvals in all jurisdictions in which the ownership or lease of its property or the conduct of its business requires such qualification

(e) Valid Sale; Binding Obligations . This Agreement and AMC’s Transaction Documents have been duly executed and delivered, shall effect a valid sale and/or contribution, transfer and assignment of the Receivables and the Other Conveyed Property to the Purchaser, enforceable against AMC and creditors of and purchasers from AMC; and this Agreement and AMC’s Transaction Documents constitute legal, valid and binding obligations of AMC enforceable in accordance with their respective terms, except as enforceability may be limited by bankruptcy, insolvency, reorganization or other similar laws af