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                                                                  Exhibit 4(f)63

                 AMENDMENT NO. 1 TO LOAN AND SECURITY AGREEMENT

      AMENDMENT NO. 1 TO LOAN AND SECURITY AGREEMENT (this "Amendment"), dated
as of August 10, 2004, among CAC WAREHOUSE FUNDING CORPORATION II, as borrower
(the "Borrower"), CREDIT ACCEPTANCE CORPORATION, as Originator (the
"Originator"), WACHOVIA CAPITAL MARKETS, LLC, as deal agent (the "Deal Agent")
and collateral agent (the "Collateral Agent"), WACHOVIA BANK, NATIONAL
ASSOCIATION, as liquidity agent for the VFCC Purchaser Group (the "Liquidity
Agent") and as the sole Investor (the "Investor") and VARIABLE FUNDING CAPITAL
CORPORATION, as a lender (and together with the Liquidity Agent, the "Lenders").

      Capitalized terms used and not defined in this Amendment shall have the
meanings given such terms in the Loan and Security Agreement, dated as of
September 30, 2003 (the "Loan Agreement"), among the Borrower, the Originator,
the Investors, the Lenders, the Deal Agent, the Backup Servicer and the
Collateral Agent.

                             PRELIMINARY STATEMENTS

      WHEREAS, each of the signatories hereto is party to the Loan Agreement;
and

      WHEREAS, each of the signatories hereto wishes to amend the Loan Agreement
as hereinafter provided;

      NOW, THEREFORE, in consideration of the mutual covenants contained herein
and in the Loan Agreement, and other good and valuable consideration, the
receipt and adequacy of which is hereby expressly acknowledged, and intending to
be legally bound hereby, the signatories hereto agree as follows:

SECTION 1. Amendment.

            (a) Section 1.1 of the Loan Agreement is hereby amended by deleting
      the definition of "Commitment Termination Date" in its entirety and
      replacing it with the following:

            "With respect to each Purchaser Group, August 9, 2005, or with
            respect to any Purchaser Group such later date to which the
            Commitment Termination Date may be extended in the sole discretion
            of such Purchaser Group in accordance with the terms of Section
            2.1(b).".

            (b) Section 1.1 of the Loan Agreement is hereby amended by deleting
      the definition of "Facility Limit" in its entirety and replacing it with
      the following:

            "$200,000,000; as such amount may vary from time to time upon the
            written agreement of the Borrower, Credit Acceptance, the Deal Agent
            and the Liquidity Agents; provided, however, that on any date on or
            after the end of the Revolving Period with respect to all Purchaser
            Groups, the Facility Limit shall mean the

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            aggregate outstanding Capital on such date, and; provided, further,
            if the Termination Date occurs with respect to fewer than all
            Purchaser Groups, the Facility Limit shall be equal to the sum of
            the Purchaser Group Facility Limits for each Purchaser Group for
            which the Termination Date has not occurred plus the outstanding
            Capital on the Termination Date for each Purchaser Group for which
            the Termination Date has occurred.".

            (c) Section 1.1 of the Loan Agreement is hereby amended by deleting
      clause (a) of the definition of "Purchaser Group Facility Limit" in its
      entirety and replacing it with the following:

            "With respect to each Purchaser Group, the amount so identified on
            the Joinder related to such Purchaser Group, and with respect to the
            VFCC Purchaser Group, $200,000,000.".

            (d) Section 2.16(a)(ii) of the Loan Agreement is hereby amended by
      deleting Section 2.16(a)(ii) in its entirety and replacing it with the
      following:

            "Unless the Take-Out is to be effected on a Payment Date (in which
            case the relevant calculations with respect to such Take-Out shall
            be reflected on the applicable Monthly Report), the Servicer shall
            deliver to the Deal Agent an Officer's Certificate, together with
            evidence to the reasonable satisfaction of the Deal Agent (which
            evidence may consist solely of the Officer's Certificate signed by
            an officer of the Servicer) that the Borrower shall have sufficient
            funds on the related Take-Out Date to effect the contemplated
            Take-Out in accordance with this Agreement. In effecting the
            Take-Out, the Borrower may use the proceeds of sales of the Loans
            (which sales must be made in arm's-length transactions);".

      SECTION 2. Conditions to Effectiveness. This Amendment shall become
effective on and as of the date hereof, upon the receipt by the Deal Agent of
(i) an amount equal to $375,000 in immediately available funds payable by the
Borrower and (ii) an executed counterpart of this Amendment from each party
hereto.

      SECTION 3. Severability of Provisions. Any provision of this Amendment
which is prohibited or unenforceable in any jurisdiction shall, as to such
jurisdiction, be ineffective to the extent of such prohibition or
unenforceability without invalidating the remaining provisions hereof or
affecting the validity or enforceability of such provision in any other
jurisdiction.

      SECTION 4. Captions. The captions in this Amendment are for convenience of
reference only and shall not define or limit any of the terms or provisions
hereof.

      SECTION 5. Agreement to Remain in Full Force and Effect. Except as amended
hereby, the Loan Agreement shall remain in full force and effect and is hereby
ratified, adopted and confirmed in all respects. All references in the Loan
Agreement to "herein," or words of like import, and all references to the Loan
Agreement in any agreement or document shall hereafter be deemed to refer to the
Loan Agreement as amended hereby.

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      SECTION 6. GOVERNING LAW. THIS AMENDMENT SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.

      SECTION 7. Execution in Counterparts. This Amendment may be executed in
any number of counterparts and by different parties hereto on separate
counterparts, each of which counterparts, when so executed and delivered, shall
be deemed to be an original and all of which counterparts, taken together, shall
constitute but one and the same Amendment.

      SECTION 8. Representations and Warranties. The Borrower hereby certifies
that (i) the representations and warranties made by it in Section 4.1 of the
Loan Agreement are true and correct as of the date hereof, as though made on and
as of the date hereof and (ii) as of the date hereof, there is no Termination
Event or Servicer Termination Event or event which, with the passage of time of
the giving of notice, could result in a Termination Event or a Servicer
Termination Event.

      SECTION 9. Waiver of Notice. Each of the parties hereto hereby waives any
notice in connection with the execution and delivery of this Amendment.

                            [SIGNATURE PAGE FOLLOWS]

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      IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed as of the date and year first above written.

                                        CAC WAREHOUSE FUNDING CORPORATION II, as
                                        Borrower

                                        By:_______________________________
                                           Name:
                                           Title:

                                        CREDIT ACCEPTANCE CORPORATION, as
                                        Originator

                                        By:_______________________________
                                           Name:
                                           Title:

                                        WACHOVIA CAPITAL MARKETS, LLC, as Deal
                                        Agent and Collateral Agent

                                        By:_______________________________
                                           Name:
                                           Title:

                                        WACHOVIA BANK, NATIONAL ASSOCIATION, as
                                        Liquidity Agent and the Sole Investor

                                        By:_______________________________
                                           Name:
                                           Title:

                                        VARIABLE FUNDING CAPITAL CORPORATION, as
                                        a Lender

                                        By: Wachovia Capital Markets, LLC, as
                                            attorney-in-fact

                                        By:_______________________________
                                           Name:
                                           Title: