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                                                              FINANCIAL GUARANTY
                                                              INSURANCE POLICY

FINANCIAL                                                    Policy No.: 51130-N
SECURITY                                                       Date of Issuance:
ASSURANCE                                                          July 19, 2001

OBLIGOR: AmeriCredit Automobile Receivables Trust 2001-B
OBLIGATIONS: $1,850,000,000 Asset Backed Notes, in the Classes
             described in Endorsement No. 1 hereto

      FINANCIAL SECURITY ASSURANCE INC. ("Financial Security"), for
consideration received, hereby UNCONDITIONALLY AND IRREVOCABLY GUARANTEES to
each Holder, subject only to the terms of this Policy (which includes each
endorsement hereto), the full and complete payment by the Obligor of Scheduled
Payments of principal of, and interest on, the Obligations.

      For the further protection of each Holder, Financial Security irrevocably
and unconditionally guarantees:

      (a) payment of the amount of any distribution of principal of, or interest
      on, the Obligations made during the Term Of This Policy to such Holder
      that is subsequently avoided in whole or in part as a preference payment
      under applicable law (such payment to be made by Financial Security in
      accordance with Endorsement No. 1 hereto).

      (b) payment of any amount required to be paid under this Policy by
      Financial Security following Financial Security's receipt of notice as
      described in Endorsement No. 1 hereto.

      Financial Security shall be subrogated to the rights of each Holder to
receive payments under the Obligations to the extent of any payment by Financial
Security hereunder.

      Except to the extent expressly modified by an endorsement hereto, the
following terms shall have the meanings specified for all purposes of this
Policy. "Holder" means the registered owner of any Obligation as indicated on
the registration books maintained by or on behalf of the Obligor for such
purpose or, if the Obligation is in bearer form, the holder of the Obligation.
"Scheduled Payments" means payments which are scheduled to be made during the
Term Of This Policy in accordance with the original terms of the Obligations
when issued and without regard to any amendment or modification of such
Obligations thereafter; payments which become due on an accelerated basis as a
result of (a) a default by the Obligor, (b) an election by the Obligor to pay
principal on an accelerated basis or (c) any other cause, shall not constitute
"Scheduled Payments" unless Financial Security shall elect, in its sole
discretion, to pay such principal due upon such acceleration to get any accrued
interest to the date of acceleration. "Term Of This Policy" shall have the
meaning set forth in Endorsement No. 1 hereto.

      This Policy sets forth in full the undertaking of Financial Security, and
shall not be modified, altered or affected by any other agreement or instrument,
including any modification or amendment thereto, or by the merger, consolidation
or dissolution the Obligor. Except to the extent expressly modified by an
endorsement hereto, the premiums paid in respect of this Policy are
nonrefundable for any reason whatsoever, including payment, or provision being
made for payment, of the Obligations prior to maturity. This Policy may not be
canceled or revoked during the Term Of This Policy. THIS POLICY IS NOT COVERED
BY THE PROPERTY/CASUALTY INSURANCE SECURITY FUND SPECIFIED IN ARTICLE 76 OF THE
NEW YORK INSURANCE LAW.

      In witness whereof, FINANCIAL SECURITY ASSURANCE INC. has caused this
Policy to be executed on its behalf by its Authorized Officer.

                                    FINANCIAL SECURITY ASSURANCE INC.
                                    By: /s/ Authorized Officer
                                       --------------------------------------
                                        Authorized Officer

A subsidiary of Financial Security Assurance Holdings Ltd.
350 Park Avenue, New York, N.Y.  10022-6022                       (212) 826-0100
Form 100NY (5/89)


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                                ENDORSEMENT NO. 1

FINANCIAL SECURITY                                    350 Park Avenue
ASSURANCE INC.                                        New York, New York  10022


OBLIGOR:          AmeriCredit Automobile Receivables Trust 2001-B

OBLIGATIONS:      $247,000,000 Class A-1 3.76% Asset Backed Notes
                  $765,000,000 Class A-2 Floating Rate Asset Backed Notes
                  $200,000,000 Class A-3 Floating Rate Asset Backed Notes
                  $638,000,000 Class A-4 5.37% Asset Backed Notes

Policy No.:  51130-N
Date of Issuance:  July 19, 2001

      1. DEFINITIONS. For all purposes of this Policy, the terms specified below
shall have the meanings or constructions provided below. Capitalized terms used
herein and not otherwise defined herein shall have the meanings provided in the
Indenture or the Sale and Servicing Agreement unless otherwise specified.

            "BUSINESS DAY" means any day other than a Saturday, Sunday, legal
holiday or other day on which commercial banking institutions in Wilmington,
Delaware or New York City, New York or any other location of any successor
Servicer, successor Owner Trustee or successor Trust Collateral Agent are
authorized or obligated by law, executive order or governmental decree to be
closed.

            "HOLDER" shall have the meaning set forth in the Indenture;
PROVIDED, HOWEVER that "Holder" shall not include the Obligor or any affiliates
or successors thereof in the event the Obligor, or any such affiliate or
successor, is a registered or beneficial owner of the Obligation.

            "INDENTURE" means the Indenture, dated as of July 12, 2001, between
the Obligor and The Chase Manhattan Bank as Trustee and Trust Collateral Agent,
as amended from time to time with the consent of Financial Security.

            "INDENTURE TRUSTEE" means Bank One, NA, in its capacity as Trustee
under the Indenture and any successor in such capacity.

            "POLICY" means this Financial Guaranty Insurance Policy and includes
each endorsement thereto.

            "RECEIPT" and "RECEIVED" mean actual delivery to Financial Security
and to the Fiscal Agent (as defined below), if any, prior to 12:00 noon, New
York City time, on a Business Day; delivery either on a day that is not a
Business Day, or after 12:00 noon, New York City time, shall be deemed to be
receipt on the next succeeding Business Day. If any notice or certificate given
hereunder by the Trust Collateral Agent is not in proper form or is not properly
completed, executed or delivered, it shall be deemed not to have been Received,
and Financial Security or its

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Fiscal Agent shall promptly so advise the Trust Collateral Agent and the Trust
Collateral Agent may submit an amended notice.

            "SALE AND SERVICING AGREEMENT" means the Sale and Servicing
Agreement dated as of July 12, 2001 among the Obligor, AmeriCredit Financial
Services, Inc., as Servicer, AFS Funding Corp., as Seller and Bank One, NA, as
Backup Servicer and Trust Collateral Agent, as such agreement may be amended,
supplemented or otherwise modified from time to time in accordance with the
terms thereof.

            "SCHEDULED PAYMENTS" means, as to each Insured Distribution Date,
payments which are required to be made to Holders in accordance with the
original terms of the Obligations when issued and without regard to any
subsequent amendment or modification of the Obligations or of the Indenture
except amendments or modifications to which Financial Security has given its
prior written consent, which payments are (i) the Noteholders' Interest
Distributable Amount with respect to the related Distribution Date, (ii) the
Noteholders' Remaining Parity Deficit Amount with respect to the related
Distribution Date and (iii) with respect to the Final Scheduled Distribution
Date for any class of Obligations, the outstanding principal amount of such
class on such Final Scheduled Distribution Date, after taking into account
reductions on such Date of such outstanding principal amount from all sources
other than this Policy. Scheduled Payments do not include payments which become
due on an accelerated basis as a result of (a) a default by the Obligor, (b) an
election by the Obligor to pay principal on an accelerated basis, (c) the
occurrence of an Event of Default under the Indenture or (d) any other cause,
unless Financial Security elects, in its sole discretion, to pay in whole or in
part such principal due upon acceleration, together with any accrued interest to
the date of acceleration. In the event Financial Security does not so elect,
this Policy will continue to guarantee payment on the Obligations in accordance
with their original terms. Scheduled Payments shall not include (x) any portion
of a Noteholders' Interest Distributable Amount due to Holders because the
appropriate notice and certificate for payment in proper form as required by
paragraph 2 hereof was not timely Received by Financial Security, (y) any
portion of a Noteholders' Interest Distributable Amount due to Holders
representing interest on any Noteholders' Interest Carryover Amount accrued from
and including the date of payment of the amount of such Noteholders' Interest
Carryover Amount pursuant hereto or (z) any Note Prepayment Amounts, unless
Financial Security elects, in its sole discretion, to pay such amount in whole
or in part. Scheduled Payments shall not include any amounts due in respect of
the Obligations attributable to any increase in interest rate, penalty or other
sum payable by the Obligor by reason of any default or event of default in
respect of the Obligations, or by reason of any deterioration of the credit
worthiness of the Obligor, nor shall Scheduled Payments include, nor shall
coverage be provided under this Policy in respect of, any taxes, withholding or
other charge with respect to any Holder imposed by any governmental authority
due in connection with the payment of any Scheduled Payment to a Holder.

            "TERM OF THIS POLICY" means the period from and including the Date
of Issuance to and including the date on which (i) all Scheduled Payments have
been paid or deemed to be paid within the meaning of Section 4.1 of the
Indenture; (ii) any period during which any Scheduled Payment could have been
avoided in whole or in part as a preference payment under applicable bankruptcy,
insolvency, receivership or similar law shall have expired and (iii) if any
proceedings requisite to avoidance as a preference payment have been commenced
prior to the occurrence of (i) and (ii), a final and nonappealable order in
resolution of each such proceeding has been entered.


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            "TRUST COLLATERAL AGENT" means The Chase Manhattan Bank in its
capacity as Trust Collateral Agent under the Indenture, acting as agent for the
Indenture Trustee in accordance with the terms of the Indenture, and any
successor in such capacity.

      2. NOTICES AND CONDITIONS TO PAYMENT IN RESPECT OF SCHEDULED PAYMENTS.
Following Receipt by Financial Security of a notice and certificate from the
Trust Collateral Agent in the form attached as Exhibit A to this Endorsement,
Financial Security will pay any amount payable hereunder in respect of Scheduled
Payments on the Obligations out of the funds of Financial Security on the later
to occur of (a) 12:00 noon, New York City time, on the third Business Day
following such Receipt; and (b) 12:00 noon, New York City time, on the date on
which such payment is due on the Obligations. Payments due hereunder in respect
of Scheduled Payments will be disbursed to the Trust Collateral Agent by wire
transfer of immediately available funds.

            Financial Security shall be entitled to pay any amount hereunder in
respect of Scheduled Payments on the Obligations, including any amount due on
the Obligations on an accelerated basis, whether or not any notice and
certificate shall have been Received by Financial Security as provided above
provided, however, that by acceptance of this Policy the Trust Collateral Agent
agrees to provide to Financial Security, upon Financial Security's request to
the Trust Collateral Agent, a notice and certificate in respect of any such
payments made by Financial Security. Financial Security shall be entitled to pay
hereunder any amount that becomes due on the Obligations on an accelerated basis
at any time or from time to time after such amount becomes due, in whole or in
part, prior to the scheduled date of payment thereof; Scheduled Payments insured
hereunder shall not include interest, in respect of principal paid hereunder on
an accelerated basis, accruing from and after the date of such payment of
principal. Financial Security's obligations hereunder in respect of Scheduled
Payments shall be discharged to the extent funds are disbursed by Financial
Security as provided herein whether or not such funds are properly applied by
the Trust Collateral Agent.

      3. NOTICES AND CONDITIONS TO PAYMENT IN RESPECT OF SCHEDULED PAYMENTS
AVOIDED AS PREFERENCE PAYMENTS. If any Scheduled Payment is avoided as a
preference payment under applicable bankruptcy, insolvency, receivership or
similar law, Financial Security will pay such amount out of the funds of
Financial Security on the later of (a) the date when due to be paid pursuant to
the Order referred to below or (b) the first to occur of (i) the fourth Business
Day following Receipt by Financial Security from the Trust Collateral Agent of
(A) a certified copy of the order (the "ORDER") of the court or other
governmental body that exercised jurisdiction to the effect that the Holder is
required to return Scheduled Payments made with respect to the Obligations
during the Term Of This Policy because such payments were avoidable as
preference payments under applicable bankruptcy law, (B) a certificate of the
Holder that the Order has been entered and is not subject to any stay and (C) an
assignment duly executed and delivered by the Holder, in such form as is
reasonably required by Financial Security, and provided to the Holder by
Financial Security, irrevocably assigning to Financial Security all rights and
claims of the Holder relating to or arising under the Obligations against the
estate of the Obligor or otherwise with respect to such preference payment or
(ii) the date of Receipt by Financial Security from the Trust Collateral Agent
of the items referred to in clauses (A), (B) and (C) above if, at least four
Business Days prior to such date of Receipt, Financial Security shall have
Received written notice from the Trust Collateral Agent that such items were to
be delivered on such date and such date was specified in such notice. Such
payment shall be disbursed to the receiver, conservator, debtor-in-


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possession or trustee in bankruptcy named in the Order and not to the Trust
Collateral Agent or any Holder directly (unless a Holder previously paid such
amount to the receiver, conservator, debtor-in-possession or trustee in
bankruptcy named in the Order, in which case such payment shall be disbursed to
the Trust Collateral Agent for distribution to such Holder upon proof of such
payment reasonably satisfactory to Financial Security). In connection with the
foregoing, Financial Security shall have the rights provided pursuant to Section
6.2 of the Sale and Servicing Agreement.

      4. GOVERNING LAW. This Policy shall be governed by and construed in
accordance with the laws of the State of New York without giving effect to the
conflict of laws principles thereof.

      5. FISCAL AGENT. At any time during the Term Of This Policy, Financial
Security may appoint a fiscal agent (the "FISCAL AGENT") for purposes of this
Policy by written notice to the Trust Collateral Agent at the notice address
specified in the Indenture specifying the name and notice address of the Fiscal
Agent. From and after the date of receipt of such notice by the Trust Collateral
Agent, (i) copies of all notices and, documents required to be delivered to
Financial Security pursuant to this Policy shall be simultaneously delivered to
the Fiscal Agent and to Financial Security and shall not be deemed Received
until Received by both, and (ii) all payments required to be made by Financial
Security under this Policy may be made directly by Financial Security or by the
Fiscal Agent on behalf of Financial Security. The Fiscal Agent is the agent of
Financial Security only and the Fiscal Agent shall in no event be liable to any
Holder for any acts of the Fiscal Agent or any failure of Financial Security to
deposit, or cause to be deposited, sufficient funds to make payments due under
the Policy.

      6. WAIVER OF DEFENSES. To the fullest extent permitted by applicable law,
Financial Security agrees not to assert, and hereby waives, for the benefit of
each Holder, all rights (whether by counterclaim, setoff or otherwise) and
defenses (including, without limitation, the defense of fraud), whether acquired
by subrogation, assignment or otherwise, to the extent that such rights and
defenses may be available to Financial Security to avoid payment of its
obligations under this Policy in accordance with the express provisions of this
Policy.

      7. NOTICES. All notices to be given hereunder shall be in writing (except
as otherwise specifically provided herein) and shall be mailed by registered
mail or personally delivered or telecopied to Financial Security as follows:

            Financial Security Assurance Inc.
            350 Park Avenue
            New York, NY  10022
            Attention:  Senior Vice President - Transaction Oversight Department
            Re:  AmeriCredit Automobile Receivables Trust 2001-B
            Policy No.:  51130-N
            Telecopy No.:  (212) 339-3518
            Confirmation:  (212) 826-0100

            Financial Security may specify a different address or addresses by
writing mailed or delivered to the Trust Collateral Agent.



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      8. PRIORITIES. In the event that any term or provision of the face of this
Policy is inconsistent with the provisions of this Endorsement, the provisions
of this Endorsement shall take precedence and shall be binding.

      9. EXCLUSIONS FROM INSURANCE GUARANTY FUNDS. This Policy is not covered by
the Property/Casualty Insurance Security Fund specified in Article 76 of the New
York Insurance Law. This Policy is not covered by the Florida Insurance Guaranty
Association created under Part II of Chapter 631 of the Florida Insurance Code.
In the event that Financial Security were to become insolvent, any claims
arising under this Policy are excluded from coverage by the California Insurance
Guaranty Association, established pursuant to Article 14.2 of Chapter 1 of Part
2 of Division 1 of the California Insurance Code.

      10. SURRENDER OF POLICY. The Trust Collateral Agent shall surrender this
Policy to Financial Security for cancellation upon expiration of the Term Of
This Policy.


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      IN WITNESS WHEREOF, FINANCIAL SECURITY ASSURANCE INC. has caused this
Endorsement No. 1 to be executed by its Authorized Officer.

                                    FINANCIAL SECURITY ASSURANCE INC.

                                    By:   /s/ Authorized Officer
                                         -------------------------------------
                                          Authorized Officer



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                                    EXHIBIT A

                              To Endorsement No. 1

                         NOTICE OF CLAIM AND CERTIFICATE

                     (Letterhead of Trust Collateral Agent)

Financial Security Assurance Inc.
350 Park Avenue
New York, NY  10022

            Re:   AMERICREDIT AUTOMOBILE RECEIVABLES TRUST 2001-B

            The undersigned, a duly authorized officer of Bank One, NA (the
"Trust Collateral Agent"), hereby certifies to Financial Security Assurance Inc.
("Financial Security"), with reference to Financial Guaranty Insurance Policy
No. 51130-N dated July 19, 2001 (the "Policy") issued by Financial Security in
respect of the $247,000,000 Class A-1 3.76% Asset Backed Notes, $765,000,000
Class A-2 Floating Rate Asset Backed Notes, $200,000,000 A-3 Floating Rate Asset
Backed Notes and $638,000,000 Class A-4 5.37 Asset Backed Notes of the
above-referenced Trust (the "Obligations"), that:

      (i) The Trust Collateral Agent is the Trust Collateral Agent for the
Holders under the Indenture.

      (ii) The sum of all amounts on deposit (or scheduled to be on deposit) in
the Note Distribution Account and available for distribution to the Holders
pursuant to the Indenture will be $ _______________ (the "Shortfall") less than
the aggregate amount of Scheduled Payments due on __________________.

      (iii) The Trust Collateral Agent is making a claim under the Policy for
the Shortfall to be applied to the payment of Scheduled Payments.

      (iv) The Trust Collateral Agent agrees that, following receipt of funds
from Financial Security, it shall (a) hold such amounts in trust and apply the
same directly to the payment of Scheduled Payments on the Obligations when due;
(b) not apply such funds for any other purpose; (c) not commingle such funds
with other funds held by the Trust Collateral Agent and (d) maintain an accurate
record of such payments with respect to each Obligation and the corresponding
claim on the Policy and proceeds thereof, and, if the Obligation is required to
be surrendered or presented for such payment, shall stamp on each such
Obligation the legend "$[insert applicable amount] paid by Financial Security
and the balance hereof has been cancelled and reissued" and then shall deliver
such Obligation to Financial Security.

      (v) The Trust Collateral Agent, on behalf of the Holders, hereby assigns
to Financial Security the rights of the Holders with respect to the Obligations
to the extent of any payments under the Policy, including, without limitation,
any amounts due to the Holders in respect of securities law violations arising
from the offer and sale of the Obligations. The foregoing assignment is in
addition to, and not in limitation of, rights of subrogation otherwise available
to


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Financial Security in respect of such payments. Payments to Financial Security
in respect of the foregoing assignment shall in all cases be subject to and
subordinate to the rights of the Holders to receive all Scheduled Payments in
respect of the Obligations. The Trust Collateral Agent shall take such action
and deliver such instruments as may be reasonably requested or required by
Financial Security to effectuate the purpose or provisions of this clause (v).

      (vi) The Trust Collateral Agent, on behalf of the Holders, hereby appoints
Financial Security as agent and attorney-in-fact for the Trust Collateral Agent
and each such Holder in any legal proceeding with respect to the Obligations.
The Trust Collateral Agent hereby agrees that, so long as an Insurer Default (as
defined in the Indenture) shall not exist, Financial Security may at any time
during the continuation of any proceeding by or against the Obligor under the
United States Bankruptcy Code or any other applicable bankruptcy, insolvency,
receivership, rehabilitation or similar law (an "Insolvency Proceeding") direct
all matters relating to such Insolvency Proceeding, including without
limitation, (A) all matters relating to any claim in connection with an
Insolvency Proceeding seeking the avoidance as a preferential transfer of any
payment made with respect to the Obligations (a "Preference Claim"), (B) the
direction of any appeal of any order relating to any Preference Claim at the
expense of Financial Security but subject to reimbursement as provided in the
Insurance Agreement and (C) the posting of any surety, supersedeas or
performance bond pending any such appeal. In addition, the Trust Collateral
Agent hereby agrees that Financial Security shall be subrogated to, and the
Trust Collateral Agent on its behalf and on behalf of each Holder, hereby
delegates and assigns, to the fullest extent permitted by law, the rights of the
Trust Collateral Agent and each Holder in the conduct of any Insolvency
Proceeding, including, without limitation, all rights of any party to an
adversary proceeding or action with respect to any court order issued in
connection with any such Insolvency Proceeding.

      (vii) Payment should be made by wire transfer directed to [SPECIFY
ACCOUNT].

            Unless the context otherwise requires, capitalized terms used in
this Notice of Claim and Certificate and not defined herein shall have the
meanings provided in the Policy.


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      IN WITNESS WHEREOF, the Trust Collateral Agent has executed and delivered
this Notice of Claim and Certificate as of the ___ th day of ___________, 20__.

                                    BANK ONE, NA,
                                    as Trust Collateral Agent

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


----------------------------------------------------

For Financial Security or Fiscal Agent Use Only

Wire transfer sent on ___________ By_________________________
Confirmation Number ______________________.



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