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                                                                  EXHIBIT 4(f)63

                                                                  EXECUTION COPY

                 AMENDMENT NO. 3 TO LOAN AND SECURITY AGREEMENT

     AMENDMENT NO. 3 TO LOAN AND SECURITY AGREEMENT (this "Amendment"), dated as
of July 31, 2005, 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. 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, December 15, 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).".

     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 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

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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.

     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]


                                       2

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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: /s/ Douglas W. Busk
                                            ------------------------------------
                                        Name: Douglas W. Busk
                                        Title: Treasurer


                                        CREDIT ACCEPTANCE CORPORATION, as
                                        Originator


                                        By: /s/ Douglas W. Busk
                                            ------------------------------------
                                        Name: Douglas W. Busk
                                        Title: Treasurer


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


                                        By: /s/ Chad Kobos
                                            ------------------------------------
                                        Name: Chad Kobos
                                        Title: Director


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


                                        By: /s/ Kevin T. McConnell
                                            ------------------------------------
                                        Name: Kevin T. McConnell
                                        Title: Director


                                        VARIABLE FUNDING CAPITAL CORPORATION,
                                        as a Lender

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


                                        By: /s/ DOUGLAS R. WILSON, SR.
                                            ------------------------------------
                                        Name: DOUGLAS R. WILSON, SR.
                                        Title: VICE PRESIDENT