EXECUTION COPY SPREAD ACCOUNT AGREEMENT

Exhibit 10.4

EXECUTION COPY

SPREAD ACCOUNT AGREEMENT

among

AMERICREDIT AUTOMOBILE RECEIVABLES TRUST 2005-A-X,

as Issuer,

XL CAPITAL ASSURANCE INC.,

as Insurer,

and

WELLS FARGO BANK, NATIONAL ASSOCIATION,

as Trustee, as Trust Collateral Agent and as Collateral Agent

Dated as of January 27, 2005

TABLE OF CONTENTS

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SPREAD ACCOUNT AGREEMENT

This SPREAD ACCOUNT AGREEMENT, dated as of January 27, 2005 (this “Agreement”), is among AMERICREDIT AUTOMOBILE RECEIVABLES TRUST 2005-A-X, as issuer (the “Issuer”), XL CAPITAL ASSURANCE INC., as insurer (the “Insurer”), and WELLS FARGO BANK, NATIONAL ASSOCIATION as trustee (in such capacity, the “Trustee” ), as trust collateral agent (in such capacity the “Trust Collateral Agent”) and as collateral agent (in such capacity, the “Collateral Agent”).

RECITALS

WHEREAS, the Issuer was formed pursuant to the trust agreement dated as of January 6, 2005 as amended and restated as of January 27, 2005 (as amended from time to time, the “Trust Agreement”), between AFS SenSub Corp., as seller, (the ”Seller”) and Wilmington Trust Company, as owner trustee (the “Owner Trustee”).

WHEREAS, pursuant to a sale and servicing agreement, dated as of January 27, 2005 (the “Sale and Servicing Agreement”) among the Issuer, the Seller, the Servicer, the Trust Collateral Agent and the Backup Servicer, the Seller sold to the Issuer all of its right, title and interest in and to the Receivables and Other Conveyed Property.

WHEREAS, pursuant to the indenture, dated as of January 27, 2005 (the ”Indenture”), among the Issuer, the Trustee and the Trust Collateral Agent, the Issuer pledged all of its right, title and interest in and to the Collateral to the Trust Collateral Agent on behalf of the Issuer Secured Parties.

WHEREAS, the Issuer requested that the Insurer issue the Note Policy to the Trustee to guarantee payment of the Insured Payments on each Distribution Date, in respect of the Notes.

WHEREAS, in consideration of the issuance of the Note Policy, the Issuer and the Servicer have agreed that the Insurer shall have certain rights as Controlling Party to the extent set forth in the Basic Documents, with respect to the Collateral.

In consideration of the premises, and for other good and valuable consideration, the adequacy, receipt and sufficiency of which are hereby acknowledged the parties hereto agree as follows:

ARTICLE I

DEFINITIONS

Section 1.01. Definitions. Unless otherwise defined in this Agreement, the following terms shall have the following meanings:

“ Accelerated Payment Amount Shortfall ” has the meaning set forth in Section 1.1 of the Sale and Servicing Agreement.

“ AmeriCredit ” means AmeriCredit Financial Services, Inc.

“ Cash Collateral Deposit ” has the meaning set forth in Section 3.06(a).

“ Cash Collateralized Receivable ” means a Delinquent Receivable for which a deposit has been made to the Spread Account by the Servicer pursuant to Section 3.06(a).

“ Collateral Agent ” means, initially Wells Fargo Bank, National Association, in its capacity as collateral agent on behalf of the Issuer Secured Parties, including its successors in interest, until a successor Person shall have become the Collateral Agent pursuant to Section 4.05 and thereafter “Collateral Agent” shall mean such successor Person.

“ Collateral Agent Fee ” means as designated in the fee letter between Collateral Agent and AmeriCredit.

“ Controlling Party ” means the Person designated as the Controlling Party at such time pursuant to Section 6.01.

“ Cumulative Net Loss ” means the positive difference between (i) the sum of (A) the aggregate Principal Balance of all Liquidated Receivables plus (B) aggregate Cram Down Losses minus (ii) Liquidation Proceeds received with respect to the Receivables described in clause (i).

“ Cumulative Net Loss Ratio ” means the ratio, expressed as a percentage, computed by dividing: (a) the sum (without duplication) of (i) Cumulative Net Losses and (ii) the product of (x) 0.50 and (y) the aggregate Principal Balance of all Receivables which are more than ninety (90) days past due as of the end of the related Collection Period; by (b) the Initial Pool Balance.

“ Default ” means, (i) if the Insurer is then the Controlling Party, any Insurance Agreement Event of Default and (ii) if the Trustee is then the Controlling Party, any Event of Default under Section 5.1 of the Indenture.

“ Defaulted Receivable ” means a Receivable (i) with respect to which (A) 10% or more of a Scheduled Receivables Payment is more than ninety (90) days past due, (B) the Servicer has repossessed the related Financed Vehicle (and any applicable redemption period has expired), or (C) such Receivable is in default and the Servicer has charged-off such Receivable in accordance with the credit and collection policy attached as Schedule C to the Sale and Servicing Agreement or otherwise has determined in good faith that payment thereunder are not likely to be resumed, or (ii) which is a Sold Receivable.

“ Delinquency Ratio ” means, the ratio (expressed as a percentage) computed by dividing: (a) the aggregate Principal Balance of all Receivables which were Delinquent Receivables as of the close of business on the last day of the related Collection Period minus the aggregate Principal Balance of all Cash Collateralized Receivables by (b) the sum of the aggregate Principal Balance of all Receivables as of the close of business on the first day of the related Collection Period.

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

“ Final Termination Date ” means the date that is the later of (i) the Insurer Termination Date and (ii) the Trustee Termination Date.

“ Gross Default Ratio ” means, the ratio expressed as a percentage, the numerator of which is the aggregate Principal Balance of all Defaulted Receivables since the Closing Date and the denominator of which is the Initial Pool Balance.

“ Initial Pool Balance ” means the Pool Balance as of the Cutoff Date.

“ Insured Payments ” has the meaning set forth in the Note Policy.

“ Insurer Termination Date ” means the date which is the latest of (i) the date of the expiration of the Note Policy and the cancellation and return thereof to the Insurer, (ii) the date on which the Insurer shall have received payment and performance in full of all Insurer Issuer Secured Obligations and (iii) the latest date on which any payment referred to above could be avoided as a preference or otherwise under the United States Bankruptcy Code or any other similar federal or state law relating to insolvency, bankruptcy, rehabilitation, liquidation or reorganization, as specified in an Opinion of Counsel delivered to the Collateral Agent, the Insurer and the Trustee.

“ Issuer ” means AmeriCredit Automobile Receivables Trust 2005-A-X.

“ Issuer Secured Obligations ” means the Issuer Secured Obligations under the Indenture and the “Issuer Insured Obligations” under any Related Series Spread Account Agreement.

“ Issuer Secured Parties ” means the Issuer Secured Parties under the Indenture and the “Issuer Secured Parties” under any Related Series Spread Account Agreement.

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“ Level 1 Cumulative Net Loss Test ” means, for any Distribution Date specified below, the Cumulative Net Loss Ratio for the related Collection Period is greater than the percentage set forth opposite such Distribution Date:

“ Level 1 Delinquency Test ” means, for any Distribution Date, the arithmetic average of the monthly Delinquency Ratios for the three immediately preceding Collection Periods is greater than the percentage set forth opposite such Distribution Date plus 0.25% for each November through April Distribution Dates:

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“ Level 1 Gross Default Test ” means, for any Distribution Date specified below, the Gross Default Ratio for the related Collection Period is greater than the percentage set forth opposite such Distribution Date:

“ Level 1 Trigger Event ” means any violation of the Level 1 Cumulative Net Loss Test, the Level 1 Delinquency Test (unless amounts are deposited to the Spread Account with respect to the Cash Collateral Deposit pursuant to Section 3.06) or the Level 1 Gross Default Test.

“ Level 2 Cumulative Net Loss Test ” means, for any Distribution Date specified below, the Cumulative Net Loss Ratio for the related Collection Period is greater than the percentage set forth in the section of the AmeriCredit 2005-A-X Letter Agreement entitled “Level 2 Trigger Event: Level 2 Cumulative Net Loss Test.”

“ Level 2 Delinquency Test ” means, for any Distribution Date, the arithmetic average of the monthly Delinquency Ratios for the three immediately preceding Collection Periods is greater than the percentage set forth in the section of the AmeriCredit 2005-A-X Letter Agreement entitled “Level 2 Trigger Event: Level 2 Delinquency Test.”

“ Level 2 Gross Default Test ” means, for any Distribution Date specified below, the Gross Default Ratio for the related Collection Period is greater than the percentage set forth in the section of the AmeriCredit 2005-A-X Letter Agreement entitled “Level 2 Trigger Event: Level 2 Gross Default Test.”

“ Level 2 Trigger Event ” means the occurrence of any of the following (A) a Servicer Termination Event, (B) violation of the Level 2 Cumulative Net Loss Test, (C) violation of the Level 2 Delinquency Test (D) violation of the Level 2 Gross Default Test or (E) an Insurance Agreement Event of Default.

“ Liquidation Proceeds ” has the meaning set forth in Section 1.1 of the Sale and Servicing Agreement.

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“ Non Controlling Party ” means, at any time, the Issuer Secured Party that is not the Controlling Party at such time.

“ Outstanding Pool Balance ” means the sum of the Pool Balance as of the end of the related Collection Period.

“ Overcollateralization Amount ” means 15%; provided , however , if each of the “Step-Down Conditions” set forth in the AmeriCredit 2005-A-X Letter Agreement are satisfied on a Distribution Date set forth in the following table, the Overcollateralization Amount shall be reduced to the amount set forth with respect to such Distribution Date in the following table; provided, further, however, if any of such “Step-Down Conditions” are not satisfied on any Distribution Date in the following table, the Overcollateralization Amount for such Distribution Date and each following Distribution Date shall equal the Overcollateralization Amount immediately prior to the date that any such “Step-Down Condition” is not satisfied:

“ Premium Letter ” has the meaning set forth in the Insurance Agreement.

“ Related Series ” means each securitization transaction (a) relating to assets sold by AmeriCredit to the Seller or another seller, (b) pursuant to which notes or certificates were issued by an issuer and certain distributions on such notes or certificates were insured by the Insurer and (c) of which the Collateral Agent has received notice in substantially the form attached hereto as Exhibit A.

“ Related Series Accelerated Payment Amount Shortfall ” means, with respect to each Related Series, after the twelfth distribution date for such Related Series on any distribution date on which a Related Series Collateral Support Shortfall is greater than zero the shortfall in the amount available in the Related Series Spread Account to pay the “Accelerated Payment Amount Shortfall” as defined in the Related Series Spread Account Agreement.

“ Related Series Collateral Agent ” means, with respect to each Related Series, the “Collateral Agent” as defined in the Related Series Spread Account Agreement.

“ Related Series Collateral Support Shortfall ” means on any distribution date with respect to a Related Series, the excess, if any, of (A) the sum of (1) the Requisite Amount (as defined in the Related Series Spread Account Agreement) on such

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Distribution Date and (2) the product of (x) the Overcollateralization Amount (as defined in the Related Series Spread Account Agreement) on such distribution date and (y) the Related Series Pool Balance on such distribution date over (B) the sum of (1) the amount in the Related Series Spread Account on such distribution date, if any, (2) the excess, if any, of the Related Series Pool Balance over the Related Series Note Balance on such distribution date and (3) the Related Series Risk in Force Amount, if applicable. For purposes of the immediately preceding sentence, (a) the amount in the Related Series Spread Account and the Related Series Note Balance on a distribution date will be calculated after giving effect to all deposits to, and withdrawals from, the Related Series Spread Account and payments of principal on the notes issued with respect to such Related Series, respectively, on such distribution date and any adjustments to the Related Series Risk in Force Amount on such distribution date.

“ Related Series Insurance Agreement ” means, with respect to each Related Series, the “Insurance Agreement” as defined in the Related Series Spread Account Agreement.

“ Related Series Insurer Payment Amounts ” means, with respect to each Related Series, any amounts due and payable to the Insurer under the Related Series Insurance Agreement.

“ Related Series Note Balance ” means, with respect to each Related Series, the Outstanding Amount (as defined in the Indenture) of the Notes issued in connection with such Related Series.

“ Related Series Pool Balance ” means, with respect to each Related Series, the “Pool Balance” as defined in the Related Series SSA.

“ Related Series Requisite Amount Shortfall ” means, with respect to each Related Series, after the twelfth distribution date for such Related Series on any distribution date on which a Related Series Collateral Support Shortfall is greater than zero, the excess, if any, of (a) the “ Requisite Amount” as defined in the Related Series Spread Account Agreement (without giving effect to any increase in such amount due to any “ Level 1 Trigger Event” or “ Level 2 Trigger Event” as such terms are defined in the Related Series Spread Account Agreement) over (b) the amount on deposit in the Related Series Spread Account (after giving effect to any withdrawals therefrom or deposits therein, except for (i) deposits therein from the Spread Account or any other Related Series Spread Account or (ii) any other amounts deposited therein that, under the terms of the Related Series Spread Account Agreement, are excluded for purposes of determining whether the amount therein equals the “ Requisite Amount” as defined in Related Series Spread Account Agreement).

“ Related Series Risk in Force Amount ” means, with respect to each Related Series, the “Risk in Force Amount”, if applicable, as defined in the Related Series Spread Account Agreement.

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“ Related Series SSA ” means, with respect to each Related Series, the “Sale and Servicing Agreement” as defined in the Related Series Spread Account Agreement.

“ Related Series Spread Account ” means, with respect to each Related Series, the “Spread Account” as defined in the Related Series Spread Account Agreement.

“ Related Series Spread Account Agreement ” means, with respect to each Related Series, the spread account agreement among the Insurer, the collateral agent for such Related Series and any other parties that may be a party thereto, together with any amendments or supplements thereto.

“ Related Series Spread Account Claim Amount ” means, with respect to each Related Series, the shortfall in the amount available in the Related Series Spread Account to pay the “Spread Account Claim Amount” as defined in the Related Series Spread Account Agreement.

“ Requisite Amount ” will equal the Spread Account Initial Deposit on the Closing Date, and thereafter, on each Distribution Date, the Requisite Amount shall be equal to 2.0% of the Initial Pool Balance, provided , however , that (i) on each Distribution Date upon which a Level 1 Trigger Event has occurred and is continuing, and upon each Distribution Date thereafter (unless such Level 1 Trigger Event has been cured for three consecutive months) the Requisite Amount shall be equal to the greater of (x) 5.0% of the Outstanding Pool Balance or (y) 4.0% of the Initial Pool Balance; and (ii) on each Distribution Date upon which a Level 2 Trigger Event has occurred and upon each Distribution Date thereafter, the Requisite Amount shall be equal to 100% of the outstanding principal balance of the Notes.

“ Risk in Force Amount ” has the meaning set forth in the Premium Letter.

“ Security Interests ” means the security interests and Liens in the Spread Account Agreement Collateral granted pursuant to Section 2.01.

“ Seller ” means AFS SenSub Corp.

“ Spread Account ” means the account designated as such, established and maintained pursuant to Article Three.

“ Spread Account Agreement Collateral ” has the meaning set forth in Section 2.01.

“ Spread Account Claim Amount ” has the meaning set forth in Section 1.1 of the Sale and Servicing Agreement.

“ Step-Down Conditions ” has the meaning set forth in the AmeriCredit 2005-A-X Letter Agreement.

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“ Trigger Event ” means a Level 1 Trigger Event or a Level 2 Trigger Event.

“ Trustee Termination Date ” means the date which is the latest of the date on which (i) the Trustee shall have received, as Trustee for the holders of the Notes, payment and performance in full of all Trustee Issuer Secured Obligations and (ii) all payments in respect of the Notes shall have been made and the Indenture shall have been satisfied and discharged pursuant to the terms of Article IV of the Indenture.

“ Uniform Commercial Code ” or “ UCC” means the Uniform Commercial Code in effect in the relevant jurisdiction, as the same may be amended from time to time.

Section 1.02. Other Definitional Provisions.

(a) Capitalized terms used but not otherwise defined herein shall have the meanings set forth in the Sale and Servicing Agreement or the Indenture, as the case may be.

(b) The terms “ hereof,” “ herein” or “ hereunder,” unless otherwise modified by more specific reference, shall refer to this Agreement in its entirety. Unless otherwise indicated in context, the terms “Article,” “Section,” “Appendix,” “Exhibit” or “Annex” shall refer to an Article or Section of, or Appendix, Exhibit or Annex to, this Agreement. The definition of a term shall include the singular, the plural, the past, the present, the future, the active and the passive forms of such term.

ARTICLE II

THE SPREAD ACCOUNT AGREEMENT COLLATERAL

Section 2.01. Grant of Security Interest by the Issuer. In order to secure the performance of Issuer Secured Obligations, to the extent provided herein, the Issuer hereby pledges, assigns, grants, transfers and conveys to the Collateral Agent, on behalf of and for the benefit of the Issuer Secured Parties, a lien on and security interest in (which lien and security interest is intended to be prior to all other Liens), all of its right, title and interest in and to the following (all being collectively referred to herein as the “ Spread Account Agreement Collateral” and constituting Spread Account Agreement Collateral hereunder):

(a) the Spread Account established pursuant to Section 3.01, and each other account owned by the Issuer and maintained by the Collateral Agent (including, without limitation, the Spread Account Initial Deposit related thereto and all additional monies, checks, securities, investments and other documents from time to time held in or evidencing any such accounts);

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(b) all of the Issuer’s right, title and interest in and to investments made with proceeds of the property described in clause (a) above, or made with amounts on deposit in the Spread Account; and

(c) all distributions, revenues, products, substitutions, benefits, profits and proceeds, in whatever form, of any of the foregoing whether now owned or hereafter acquired.

Section 2.02. Priority. The Issuer intends the security interests in favor of the Issuer Secured Parties to be prior to all other Liens in respect of the Spread Account Agreement Collateral, and the Issuer shall take all actions necessary to obtain and maintain, in favor of the Collateral Agent, for the benefit of the Issuer Secured Parties, a first lien on and a first priority, perfected security interest in the Spread Account Agreement Collateral including, without limitation, the filing of a UCC-1 financing statement relating to the Spread Account Agreement Collateral. Subject to the provisions hereof specifying the rights and powers of the Collateral Agent at the direction of the Controlling Party from time to time to control certain specified matters relating to the Spread Account Agreement Collateral, each Issuer Secured Party shall have all of the rights, remedies and recourse with respect to the Spread Account Agreement Collateral afforded a Secured Party under the Uniform Commercial Code, and all other applicable law in addition to, and not in limitation of, the other rights, remedies and recourse granted to such Issuer Secured Parties by this Agreement or any other law relating to the creation and perfection of liens on, and security interests in, the Spread Account Agreement Collateral.

Section 2.03. Issuer Remains Liable. The Security Interests are granted as security only and shall not (i) transfer or in any way affect or modify, or relieve either the Issuer from, any obligation to perform or satisfy, any term, covenant, condition or agreement to be performed or satisfied by the Issuer under or in connection with this Agreement, the Insurance Agreement or any other Basic Documents to which it is a party or (ii) impose any obligation on any of the Issuer Secured Parties or the Collateral Agent to perform or observe any such term, covenant, condition or agreement or impose any liability on any of the Issuer Secured Parties or the Collateral Agent for any act or omission on its part relative thereto or for any breach of any representation or warranty on its part contained therein or made in connection therewith, except, in each case, to the extent provided herein and in the other Basic Documents.

Section 2.04. Delivery and Maintenance of Spread Account Agreement Collateral.

(a) The Collateral Agent agrees to maintain the Spread Account Agreement Collateral received by it (or evidence thereof, in the case of book-entry securities in the name of the Collateral Agent) and all records and documents relating thereto at the office of the Collateral Agent specified in Section 8.06 or such other address as may be approved by the Controlling Party. The Collateral Agent shall keep all Spread Account Agreement Collateral and related documentation in its possession

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separate and apart from all other property that it is holding in its possession and from its own general assets and shall maintain accurate records pertaining to the Eligible Investments and Spread Account included in the Spread Account Agreement Collateral in such a manner as shall enable the Collateral Agent and the Issuer Secured Parties to verify the accuracy of such recordkeeping. The Collateral Agent’s books and records shall at all times show that the Spread Account Agreement Collateral is held by the Collateral Agent as agent of the Issuer Secured Parties and is not the property of the Collateral Agent. The Collateral Agent will promptly report to each Issuer Secured Party and the Issuer any failure on its part to hold the Spread Account Agreement Collateral as provided in this Section 2.04(a) and will promptly take appropriate action to remedy any such failure.

(b) The Collateral Agent shall permit each of the Issuer Secured Parties, or their respective duly authorized representatives, attorneys, auditors or designees, to inspect the Spread Account Agreement Collateral in the possession of or otherwise under the control of the Collateral Agent pursuant hereto at such reasonable times during normal business hours as any such Issuer Secured Party may reasonably request upon not less than two Business Day’s prior written notice. The costs and expenses associated with any such inspection will be paid by the party making such inspection.

(c) All Spread Account Agreement Collateral shall be transferred to the Collateral Agent on behalf of the Issuer Secured Party in a manner consistent with the definition of “ Delivery” set forth in the Sale and Servicing Agreement.

(d) Notwithstanding anything to the contrary herein, the Collateral Agent: (i) is and will be acting on behalf of the Issuer Secured Parties as a securities intermediary under Article Eight of the UCC and acknowledges that it holds the Spread Account Agreement Collateral for the benefit of the Issuer Secured Parties for purposes of Section 9-313 of the UCC (ii) shall establish and maintain the Spread Account for the benefit of the Issuer Secured Parties as a holder of a security interest in the Spread Account Agreement Collateral and the Spread Account; (iii) shall treat all of the assets in the Spread Account (other than cash) as financial assets under Article Eight of the UCC; (iv) shall not hold, or exercise control (within the meaning of Article Eight or Nine of the UCC) over, the Spread Account Agreement Collateral and/ or the Spread Account for the benefit of any person or entity other than the Issuer Secured Parties; (v) has received notice of the Issuer Secured Parties’ interest in the assets contained and/or to be contained in the Spread Account; and (vi) shall take instructions only from the Issuer Secured Party constituting the Controlling Party hereunder (without any consent of and notwithstanding any alternate direction of the Issuer) with respect to the Spread Account

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and/or the Spread Account Agreement Collateral, including, without limitation, all instructions with respect to the acquisition, transfer and disposition of assets in the Spread Account and the proceeds thereof. In accordance with the choice of law governing this Agreement set forth in Section 8.14 herein, for purposes of Article Eight of the UCC the jurisdiction of the Collateral Agent is deemed to be New York.

Section 2.05. Termination and Release of Rights.

(a) On the Insurer Termination Date, the rights, remedies, powers, duties, authority and obligations conferred upon the Insurer pursuant to this Agreement in respect of the Spread Account Agreement Collateral shall terminate and be of no further force and effect and all rights, remedies, powers, duties, authority and obligations of the Insurer with respect to such Spread Account Agreement Collateral shall be automatically released; provided that any indemnity provided to or by the Insurer herein shall survive such Insurer Termination Date. If the Insurer is acting as Controlling Party on the related Insurer Termination Date, the Insurer agrees, at the expense of the Issuer, to execute and deliver such instruments as the successor Controlling Party may reasonably request to effectuate such release, and any such instruments so executed and delivered shall be fully binding on the Insurer and any Person claiming by, through or under the Insurer.

(b) On the Trustee Termination Date, the rights, remedies, powers, duties, authority and obligations, if any, conferred upon the Trustee pursuant to this Agreement in respect of the Spread Account Agreement Collateral shall terminate and be of no further force and effect and all such rights, remedies, powers, duties, authority and obligations of the Trustee with respect to such Spread Account Agreement Collateral shall be automatically released; provided that any indemnity provided to the Trustee herein shall survive such Trustee Termination Date. If the Trustee is acting as Controlling Party on the related Trustee Termination Date, the Trustee agrees, at the expense of the Issuer, to execute and deliver such instruments as the Issuer may reasonably request to effectuate such release, and any such instruments so executed and delivered shall be fully binding on the Trustee.

(c) On the Final Termination Date, the rights, remedies, powers, duties, authority and obligations conferred upon the Collateral Agent and each Issuer Secured Party pursuant to this Agreement shall terminate and be of no further force and effect and all rights, remedies, powers, duties, authority and obligations of the Collateral Agent and each Issuer Secured Party with respect to the Spread Account Agreement Collateral shall be automatically released. On the Final Termination Date, the Collateral Agent agrees, and each Issuer Secured Party agrees, at the expense of the Issuer, to execute such instruments of release, in recordable

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form if necessary, in favor of the Issuer as the Issuer may reasonably request, to deliver any Spread Account Agreement Collateral in its possession to the Issuer, and to otherwise release the lien of this Agreement and release and deliver to the Issuer the Spread Account Agreement Collateral.

Section 2.06. Non-Recourse Obligations of Issuer. Notwithstanding anything herein or in the other Basic Documents to the contrary, the parties hereto agree that the obligations of the Issuer hereunder shall be recourse only to the extent of amounts released to the Issuer pursuant to Section 3.03(b)(ii) and retained by the Issuer in accordance with the next sentence. The Issuer agrees that it shall not declare or make any payment to the Seller or AmeriCredit except in accordance with the Basic Documents. Nothing contained herein shall be deemed to limit the rights of the Noteholders under any other Basic Document.

ARTICLE III

SPREAD ACCOUNT

Section 3.01. Establishment of Spread Account; Initial Deposit into Spread Account; Maintenance of Spread Account.

(a) On or prior to the Closing Date, the Collateral Agent shall establish, at its office or at another depository institution or trust company an Eligible Deposit Account, designated, “ Spread Account—Wells Fargo Bank, National Association, as Collateral Agent for XL Capital Assurance Inc. and Wells Fargo Bank, National Association, as Trustee and Trust Collateral Agent Re: AmeriCredit Automobile Receivables Trust 2005-A-X, Class A Asset-Backed Notes Series 2005-A-X” (the “Spread Account”). The Spread Account shall be maintained by the Collateral Agent at all times separate and apart from any other account of AmeriCredit, the Seller, the Servicer or the Issuer. The Spread Account shall be maintained at the same depository institution (which depository institution may be changed from time to time in accordance with this Agreement). If the Spread Account ceases to be an Eligible Deposit Account, the Collateral Agent shall notify the Controlling Party of such fact and shall establish within five Business Days of such determination, in accordance with Section 3.04(a), a successor Spread Account thereto, which shall be an Eligible Deposit Account, at another depository institution acceptable to the Controlling Party.

(b) No withdrawals may be made of funds in the Spread Account except as provided in Section 3.03. Except as specifically provided in this Agreement, funds in the Spread Account shall not be commingled with any other moneys. All moneys deposited from time to time in the Spread Account and all investments made with such moneys shall be held by the Collateral Agent as part of the Spread Account Agreement Collateral.

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(c) On the Closing Date, Issuer shall provide or cause to be provided to the Collateral Agent for deposit into the Spread Account an amount equal to the Spread Account Initial Deposit.

(d) On each Distribution Date, after giving effect to all payments to be made on the related Distribution Date, the Collateral Agent shall cause to be maintained in the Spread Account an amount equal to the Requisite Amount in accordance with Article V of the Sale and Servicing Agreement. Any amounts deposited with respect to the Cash Collateral Deposit shall not be included for the purposes of determining whether the amount maintained in the Spread Account equals the Requisite Amount

Section 3.02. Investments.

(a) Funds which may at any time be held in the Spread Account shall be invested and reinvested by the Collateral Agent, at the written direction (which may include, subject to the provisions hereof, general standing instructions) of the Issuer (unless a Default shall have occurred and be continuing, in which case at the written direction of the Controlling Party if it so elects) or its designee received by the Collateral Agent by 1:00 p.m. New York City time, on the Business Day prior to the date on which such investment shall be made, in one or more Eligible Investments in the manner specified in Section 3.02(b) and (c). If no written direction with respect to any portion of such Spread Account is received by the Collateral Agent, the Spread Account Agreement Collateral Agent shall invest such funds overnight in money market mutual funds described in paragraph (d) of the definition of the term “Eligible Investments,” provided that the Collateral Agent shall not be liable for any loss or absence of income resulting from such investments.

(b) Each investment made pursuant to this Section on any date shall mature not later than the Business Day immediately preceding the Distribution Date next succeeding the day such investment is made or payable on demand, provided that any investment of funds in the Spread Account maintained with the Collateral Agent in any investment as to which the Collateral Agent is the obligor, if otherwise qualified as an Eligible Investment may mature on the Distribution Date next succeeding the date of such investment.

(c) Subject to the other provisions hereof, the Collateral Agent shall have sole control over each such investment and the income thereon, and any certificate or other instrument evidencing any such investment, if any, shall be delivered directly to the Collateral Agent or its agent, together with each document of transfer, if any, necessary to transfer title

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to such investment to the Collateral Agent in a manner which complies with Section 2.04 and the requirements of the definition of “Eligible Investments.”

(d) If amounts on deposit in the Spread Account are at any time invested in an Eligible Investment payable on demand, the Collateral Agent shall (i) consistent with any notice required to be given thereunder, demand that payment thereon be made on the last day such Eligible Investment is permitted to mature under the provisions hereof and (ii) demand payment of all amounts due thereunder promptly upon receipt of written notice from the Controlling Party to the effect that such investment does not constitute an Eligible Investment.

(e) All moneys on deposit in the Spread Account, together with any deposits or securities in which such moneys may be invested or reinvested, and any gains from such investments, shall constitute Spread Account Agreement Collateral hereunder subject to the Security Interests of the Issuer Secured Parties.

(f) Subject to Section 4.03, the Collateral Agent shall not be liable by reason of any insufficiency in amounts on deposit in the Spread Account resulting from any loss on any Eligible Investment included therein except for losses attributable to the Collateral Agent’s failure to make payments on Eligible Investments as to which the Collateral Agent, in its commercial capacity, is obligated. All income or loss on investments of funds in the Spread Account shall be reported by AmeriCredit as taxable income or loss.

Section 3.03. Payments; Priority of Payments.

(a) On