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                                                                     Exhibit 4.4

                                                         FINANCIAL GUARANTY
FINANCIAL                                                INSURANCE POLICY
SECURITY
ASSURANCE

OBLIGOR: AmeriCredit Automobile Receivables Trust 2002-B     Policy No.: 51294-N

OBLIGATIONS: $1,200,000,000 Asset Backed Notes, in the         Date of Issuance:
       Classes described in Endorsement No. 1 hereto               June 12, 2002

     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 TO
                       FINANCIAL GUARANTY INSURANCE POLICY

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

OBLIGOR:          AmeriCredit Automobile Receivables Trust 2002-B

OBLIGATIONS:      $205,000,000 Class A-1 1.90790% Asset Backed Notes
                  $353,000,000 Class A-2 2.71% Asset Backed Notes
                  $352,000,000 Class A-3 3.78% Asset Backed Notes
                  $317,000,000 Class A-4 4.46% Asset Backed Notes

Policy No.: 51294-N

Date of Issuance: June 12, 2002

     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 June 4, 2002, between the
Obligor and JPMorgan Chase Bank, as Trustee and Trust Collateral Agent, as
amended from time to time with the consent of Financial Security.

          "Indenture Trustee" means JPMorgan Chase Bank, 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,

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executed or delivered, it shall be deemed not to have been Received, and
Financial Security or its 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 June 4, 2002 among the Obligor, AmeriCredit Financial Services,
Inc., as Servicer, AFS Funding Corp., as Seller and JPMorgan Chase Bank, 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

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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.

          "Trust Collateral Agent" means JPMorgan Chase 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

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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-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: Managing Director - Transaction Oversight Department
               Re:  AmeriCredit Automobile Receivables Trust 2002-B
               Policy No.:  51294-N
               Telecopy No.:  (212) 339-3518
               Confirmation:  (212) 826-0100

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

     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.

          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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Policy No.: 51294-N                              Date of Issuance: June 12, 2002

                                                                       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 2002-B

           The undersigned, a duly authorized officer of JPMorgan Chase Bank,
(the "Trust Collateral Agent"), hereby certifies to Financial Security Assurance
Inc. ("Financial Security"), with reference to Financial Guaranty Insurance
Policy No. 51294-N dated June 12, 2002 (the "Policy") issued by Financial
Security in respect of the $205,000,000 Class A-1 1.90790% Asset Backed Notes,
$353,000,000 Class A-2 2.71% Asset Backed Notes, $325,000,000 Class A-3 3.78%
Asset Backed Notes and $317,000,000 Class A-4 4.46% 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

                                      A-1

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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 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__.

                            JPMORGAN CHASE BANK,
                            as Trust Collateral Agent

                            By: _________________________________________

                            Title: ______________________________________

___________________________________________________

For Financial Security or Fiscal Agent Use Only

Wire transfer sent on ___________ By_________________________
Confirmation Number ______________________.

                                      A-3