CONTRIBUTION AGREEMENT

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                                                                EXHIBIT 4(f)(91)

                                                               EXECUTION VERSION

                             CONTRIBUTION AGREEMENT

     This CONTRIBUTION AGREEMENT, dated as of April 12, 2007 (the "Agreement"),
is made between CREDIT ACCEPTANCE CORPORATION, a Michigan corporation ("CAC")
and CREDIT ACCEPTANCE FUNDING LLC 2007-1, a Delaware limited liability company
("Funding").

     Funding desires to acquire from time to time certain Dealer Loans and
related rights and collateral, including certain of CAC's rights in the Dealer
Agreements related thereto, all of the related Contracts, and the Collections
(other than Dealer Collections) derived therefrom during the full term of this
Agreement, and CAC desires to transfer, convey and assign from time to time such
Dealer Loans and related property to Funding upon the terms and conditions
hereinafter set forth. CAC has also agreed to service the Dealer Loans and
related property to be transferred, conveyed and assigned to Funding.

     In consideration of the premises and the mutual agreements set forth
herein, it is hereby agreed by and between CAC and Funding as follows:

                                    ARTICLE I
                                   DEFINITIONS

     SECTION 1.1. Definitions. Capitalized terms used herein shall have the
respective meanings specified herein or, if not so specified, the respective
meanings specified in, or incorporated by reference into, the Sale and Servicing
Agreement, and shall include in the singular number the plural and in the plural
number the singular:

     "Applicable Pool Cap" means the maximum number of Contracts that could,
under the applicable Dealer Agreement, be allocated to a pool of Contracts that
support a Dealer Loan.

     "Contributed Property" means the Initial Contributed Property and the
Subsequent Contributed Property.

     "Initial Contributed Property" means (i) the Dealer Loans listed on Exhibit
A hereto delivered to the Servicer, the Class A Insurer, the Backup Servicer and
the Trust Collateral Agent on the Closing Date and (ii) all Related Security
with respect thereto.

     "Related Security" means, with respect to any Dealer Loans, (i) all rights
under the Dealer Agreements related thereto other than the Excluded Dealer
Agreement Rights, including CAC's right to service the Dealer Loans and the
related Contracts and to receive the related servicing fees and reimbursement of
certain recovery and repossession expenses, in accordance with the terms of the
Dealer Agreements; (ii) Collections (other than Dealer Collections) after the
applicable Cut-off Date; (iii) a security interest in each Contract securing
such Dealer Loan; (iv) all records and documents relating to such Dealer Loans
and the Contracts; (v) all security interests purporting to secure payment of
such Dealer Loans; (vi) all security interests purporting to secure payment of
each Contract (including a security interest in each Financed Vehicle); (vii)
all guarantees, insurance (including insurance insuring the priority or
perfection of any Contract) or other agreements or arrangements securing the
Contracts; and (viii) all Proceeds of the

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foregoing. For the avoidance of doubt, the term "Related Security" with respect
to any Dealer Loan includes all rights arising under such Dealer Loan which
rights are attributable to advances made under such Dealer Loan as the result of
Contracts being added to the identifiable group of Contracts to which such
Dealer Loan relates after the date such Dealer Loan was sold, and not otherwise
included in Subsequent Contributed Property, including all such rights arising
after the last day of the last full Collection Period during the Revolving
Period.

     "Sale and Servicing Agreement" shall mean the Sale and Servicing Agreement
dated as of the Closing Date among CAC, Funding, Credit Acceptance Auto Dealer
Loan Trust 2007-1, as the Issuer, Wells Fargo Bank, National Association, as the
Trust Collateral Agent, Indenture Trustee and Backup Servicer.

     "Subsequent Contributed Property" means, with respect to any Distribution
Date, (i) the Dealer Loans added to Exhibit A hereto as of such Distribution
Date and (ii) all Related Security with respect thereto.

     SECTION 1.2. Other Terms. All accounting terms not specifically defined
herein shall be construed in accordance with GAAP. All terms used in Article 9
of the UCC, and not specifically defined herein, are used herein as defined in
such Article 9.

      SECTION 1.3. Computation of Time Periods. Unless otherwise stated in this
Agreement, in the computation of a period of time from a specified date to a
later specified date, the word "from" means "from and including" and the words
"to" and "until" each means "to but excluding."

                                   ARTICLE II
                      CONTRIBUTION AND SALE OF DEALER LOANS

     SECTION 2.1 Contribution and Sale of Dealer Loans. (a) In consideration of
the payments described in Section 3.1, effective as of the Closing Date, CAC
does hereby convey, assign, sell and transfer to Funding, without recourse,
except as set forth herein, all of its right, title and interest in and to the
Initial Contributed Property.

     (b) CAC hereby further agrees that on each Distribution Date during the
Revolving Period, in consideration of the payment described in Section 3.1 with
respect to such Distribution Date, CAC shall, and CAC does hereby agree to,
contribute, convey, assign, sell and transfer to Funding, without recourse,
except as set forth in this Agreement, all of its right, title and interest in
and to the Subsequent Contributed Property with respect to such Distribution
Date.

     (c) CAC hereby further agrees that the above-described conveyances shall,
without the need for any further action on the part of CAC or Funding, include
all rights arising after the end of the Revolving Period under any Dealer Loan
included in the Initial Contributed Property and Subsequent Contributed Property
which rights are attributable to advances made under such Dealer Loans as the
result of Contracts being added after the last day of the last full Collection
Period during the Revolving Period to the identifiable group of Contracts to
which such Dealer Loan relates.


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     (d) Each such contribution, sale, assignment, transfer and conveyance does
not constitute an assumption by Funding of any obligations of CAC or any other
Person to Obligors or to any other Person in connection with the Dealer Loans or
under any Contract, Dealer Agreement or other agreement and instrument relating
to the Dealer Loans.

     (e) In connection with any such foregoing conveyance, CAC agrees to record
and file on or prior to the Closing Date, at its own expense, a financing
statement or statements with respect to the Contributed Property conveyed by CAC
hereunder meeting the requirements of applicable state law in such manner and in
such jurisdictions as are necessary to perfect the interests of Funding created
hereby, and to deliver either the originals of such financing statements or a
file-stamped copy of such financing statements or other evidence of such filings
to Funding on the Closing Date.

     (f) CAC agrees that from time to time, at its expense, it will promptly
execute and deliver all instruments and documents and take all actions as may be
necessary or as Funding may reasonably request in order to perfect or protect
the interest of Funding in the Dealer Loans and other Contributed Property
purchased hereunder or to enable Funding to exercise or enforce any of its
rights hereunder. CAC shall, upon request of Funding, obtain such additional
search reports as Funding shall request. To the fullest extent permitted by
applicable law, Funding shall be authorized and permitted to file continuation
statements and amendments to financing statements and assignments thereof to
preserve and protect its right, title and interest in, to and under the
Contributed Property.

     (g) It is the express intent of CAC and Funding that the conveyance of the
Dealer Loans and other Contributed Property by CAC to Funding pursuant to this
Agreement be construed as an absolute sale and contribution of such Dealer Loans
and other Contributed Property by CAC to Funding. Further, it is not the
intention of CAC and Funding that such conveyance be deemed a grant of a
security interest in the Dealer Loans and other Contributed Property by CAC to
Funding in the nature of a consensual lien securing an obligation. However, in
the event that, notwithstanding the express intent of the parties, the Dealer
Loans and other Contributed Property are construed to constitute property of
CAC, then (i) this Agreement also shall be deemed to be, and hereby is, a
security agreement within the meaning of the UCC as enacted in the State of
Michigan; and (ii) the conveyance by CAC provided for in this Agreement shall be
deemed to be, and CAC hereby grants to Funding, a security interest in, to and
under all of CAC's right, title and interest in, to and under the Contributed
Property, to secure the rights of Funding set forth in this Agreement or as may
be determined in connection therewith by applicable law. CAC and Funding shall,
to the extent consistent with this Agreement, take such actions as may be
necessary to ensure that, if this Agreement were deemed to create such a
security interest in the Dealer Loans and other Contributed Property, such
security interest would be a perfected security interest in favor of Funding
under applicable law and will be maintained as such throughout the term of this
Agreement.

     (h) In connection with such conveyance, CAC agrees to deliver to Funding on
the Closing Date, one or more computer files or microfiche lists containing true
and complete lists of all Dealer Agreements and Dealer Loans conveyed to Funding
on the Closing Date, and all Contracts securing all such Dealer Loans,
identified by account number, dealer number and pool number. Such file or list
shall be marked as Exhibit A to this Agreement, shall be delivered to


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Funding as confidential and proprietary, and is hereby incorporated into and
made a part of this Agreement. Such list and such Exhibit A shall be
supplemented and updated by lists delivered by CAC to Funding on each
Distribution Date in the Revolving Period describing all Contributed Property
conveyed on each such Distribution Date so that, on each such date, Funding will
have an aggregate list and Exhibit A that describes all Dealer Loans conveyed by
CAC to Funding hereunder on or prior to said Distribution Date, and the related
Dealer Agreements and all Contracts securing all such Dealer Loans.

     (i) CAC will reflect the transactions described in paragraph (a) of this
Section 2.1 on its internal non-consolidated financial statements and on its
non-consolidated state tax returns as a sale or other absolute transfer of the
Dealer Loans from CAC to Funding, even though CAC will reflect this transaction
on its consolidated financial statements as an "on-balance sheet" item in
accordance with generally accepted accounting principles. CAC will present the
data in its consolidated financial statements with an accompanying footnote
describing Funding's separate existence and stating that such item is a
financing secured by the Dealer Loans and is non-recourse to CAC.

     SECTION 2.2. Servicing of Dealer Loans. The servicing, administering and
collection of the Dealer Loans shall be conducted by the Servicer then
authorized to act as such under the Sale and Servicing Agreement.

                                   ARTICLE III
                            CONSIDERATION AND PAYMENT

     SECTION 3.1. Consideration. The consideration for the Dealer Loans and
other Contributed Property conveyed on the Closing Date to Funding by CAC under
this Agreement shall be an amount equal to the net cash proceeds received by
Funding arising out of its conveyance on the Closing Date of Contributed
Property to the Issuer under the Sale and Servicing Agreement, plus 100% of the
sole membership interest in Funding. Thereafter, on each Distribution Date in
the Revolving Period, the consideration for the Dealer Loans and other
Contributed Property conveyed on such Distribution Date will be cash in the
amount of the Aggregate Outstanding Net Eligible Loan Balance of such Dealer
Loans as of such Distribution Date. The Contributed Property shall be deemed to
have a value equal to the aggregate principal amount of the Dealer Loans sold
and contributed by CAC to Funding.

     SECTION 3.2. Membership Interest. The membership interest of CAC in Funding
shall arise on the Closing Date. Such membership interest may not be sold or
otherwise transferred by CAC except as otherwise permitted in the Sale and
Servicing Agreement.

                                   ARTICLE IV
                         REPRESENTATIONS AND WARRANTIES

     SECTION 4.1. Representations and Warranties. CAC represents and warrants to
Funding, as of the Closing Date and each Distribution Date during the Revolving
Period, that:

     (a) Organization and Good Standing. CAC is duly organized and is validly
existing as a corporation in good standing under the laws of the State of
Michigan, with power and authority to own its properties and to conduct its
business as such properties are currently owned


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and such business is presently conducted, and has and had at all relevant times,
full power, authority, and legal right to acquire, own, sell, and service the
Dealer Loans and the related Contracts, and to perform its obligations under the
Basic Documents.

     (b) Due Qualification. CAC is duly qualified to do business as a foreign
corporation in good standing, and has obtained all necessary licenses and
approvals in all jurisdictions in which the ownership or lease of property or
the conduct of its business, including the servicing of the Dealer Loans and the
related Contracts as required by this Agreement, requires such qualifications
except where such failure will not have a material adverse effect.

     (c) Power and Authority. CAC has the power and authority to execute and
deliver this Agreement and the other Basic Documents to which it is a party and
to carry out their respective terms; and the execution, delivery, and
performance of this Agreement and the other Basic Documents to which it is a
party have been duly authorized by CAC by all necessary corporate action.

     (d) Valid Sale; Binding Obligations. This Agreement evidences a valid sale,
transfer, and assignment of the Contributed Property enforceable against
creditors of and purchasers from CAC; and this Agreement and the other Basic
Documents to which CAC is a party constitute legal, valid and binding
obligations of CAC enforceable in accordance with their terms, subject to the
effects of bankruptcy, insolvency, reorganization, or other similar laws
affecting the enforcement of creditors' or secured creditors' rights generally
and to general principles of equity.

     (e) No Violation. The consummation of the transactions contemplated by this
Agreement and the other Basic Documents to which it is a party and the
fulfillment of the terms hereof and thereof do not conflict with, result in any
breach of any of the terms and provisions of, or constitute (with or without
notice or lapse of time) a default under, the Articles of Incorporation or
by-laws of CAC, or any indenture, agreement, or other instrument to which CAC is
a party or by which it is or may be bound; nor result in the creation or
imposition of any Lien upon any of its properties pursuant to the terms of any
such indenture, agreement (other than this Agreement), or other instrument; or
violate any law or, to the best of CAC's knowledge, any order, rule, or
regulation applicable to CAC of any court or of any federal or state regulatory
body, administrative agency, or other governmental instrumentality having
jurisdiction over CAC or its properties.

     (f) No Proceedings. There are no proceedings or investigations pending, or
to CAC's best knowledge threatened, before any court, regulatory body,
administrative agency, or other governmental instrumentality having jurisdiction
over CAC or its properties: A) asserting the invalidity of this Agreement or any
other Basic Document to which it is a party; B) seeking to prevent the
consummation of any of the transactions contemplated by this Agreement or any
other Basic Document to which it is a party; or C) seeking any determination or
ruling that might materially and adversely affect the performance by CAC of its
obligations under, or the validity or enforceability of, this Agreement, or any
other Basic Document to which it is a party.

     (g) Place of Business. The principal place of business and chief executive
office of CAC is in Southfield, Michigan, and the office where CAC keeps all of
its Records is at the


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address listed in Section 8.3, or such other locations notified to Funding and
the Trust Collateral Agent in accordance with this Agreement in jurisdictions
where all action required by the terms of this Agreement has been taken and
completed.

     (h) Eligibility of Dealer Agreements. Each Dealer Agreement classified as
an "Eligible Dealer Agreement" (or included in any aggregation of balances of
"Eligible Dealer Agreements") by CAC in any document or report delivered
hereunder satisfied the requirements contained in the definition of Eligible
Dealer Agreement on the date so delivered.

     (i) Eligibility of Dealer Loans. Each Dealer Loan classified as an
"Eligible Loan" (or included in any aggregation of balances of "Eligible Loans")
by CAC in any document or report delivered hereunder satisfied the requirements
contained in the definition of Eligible Loan on the date so delivered. Each
Dealer Loan represents, or will represent, a non-recourse obligation of a Dealer
with respect to advances related to a pool of Contracts, and CAC has, and will
maintain, a policy that each such pool will have Contracts allocated to it (as
generated by relevant Dealer) until the number of Contracts in such pool reaches
the Applicable Pool Cap. The Applicable Pool Cap for each Dealer Loan will equal
or exceed 75.

     (j) Eligibility of Contracts. Each Contract classified as an "Eligible
Contract" (or included in any aggregation of balances of "Eligible Contracts")
by CAC in any document or report delivered hereunder satisfied the requirements
contained in the definition of Eligible Contract on the date so delivered.

     (k) Accuracy of Information. All information with respect to the Dealer
Loans and other Contributed Property provided to Funding hereunder by CAC was
true and correct in all material respects as of the date such information was
provided to Funding and did not omit to state any material facts necessary to
make the statements contained therein not misleading.

     (l) No Liens. Each Dealer Loan and the other Contributed Property has been
transferred to Funding free and clear of any Lien of any Person, and in
compliance, in all material respects, with all Applicable Laws.

     (m) No Consents. With respect to each Dealer Loan and the other Contributed
Property, all consents, licenses, approvals or authorizations of or
registrations or declarations with any Governmental Authority required to be
obtained, effected or given by CAC, in connection with the pledge of such
Contributed Property to Funding have been duly obtained, effected or given and
are in full force and effect.

     (n) Exhibit A. Exhibit A to this Agreement and each supplement or addendum
thereto is and will be an accurate and complete listing of all Dealer Loans and
the related Dealer Agreements and Contracts in all material respects on the date
each such Dealer Loan was sold to Funding hereunder, and the information
contained therein is and will be true and correct in all material respects as of
such date.

     (o) Adverse Selection. No selection procedure believed by CAC to be adverse
to the interests of Funding has been or will be used in selecting the Dealer
Agreements, Dealer Loans or Contracts.


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     (p) Contribution Agreement. This Contribution Agreement is the only
agreement pursuant to which Funding acquires Dealer Loans from CAC.

     (q) Security Interest. CAC has granted a security interest (as defined in
the UCC as enacted in the State of Michigan) to Funding in the Contributed
Property, which is enforceable in accordance with Applicable Law upon the
Closing Date. Upon the filing of UCC-1 financing statements naming Funding as
secured party and CAC as debtor, Funding shall have a first priority perfected
security interest in the Contributed Property. All filings (including, without
limitation, UCC filings) as are necessary in any jurisdiction to perfect the
interest of Funding have been made.

     (r) Credit Score. The weighted average (based on Contract principal
balance) of the Final Scores of each "Contract Group" is 665 or greater. A
"Contract Group" is a group of Contracts related to a group of Dealer Loans that
becomes Contributed Property on the Closing Date or on a particular Distribution
Date during the Revolving Period.

     (s) Use of Proceeds. No proceeds of any sale of Contributed Property will
be used (i) for a purpose that violates, or would be inconsistent with,
Regulation T, U or X promulgated by the Board of Governors of the Federal
Reserve System from time to time or (ii) to acquire any security in any
transaction which is subject to Section 12, 13 or 14 of the Securities Exchange
Act of 1934, as amended.

     (t) Taxes. CAC has filed on or before their respective due dates, all tax
returns which are required to be filed in any jurisdiction or has obtained
extensions for filing such tax returns and has paid all taxes, assessments, fees
and other governmental charges against CAC or any of its pro