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                                                                  EXHIBIT 10.1.a

                                                                  EXECUTION COPY

                                 AMENDMENT NO. 1

                            Dated as of June 25, 2004

                                       to

                             CONTRIBUTION AGREEMENT

                            Dated as of June 5, 2003

            THIS AMENDMENT NO. 1 to CONTRIBUTION AGREEMENT ("Amendment") is
entered into as of June 25, 2004 by and among BAY VIEW ACCEPTANCE CORPORATION
("Bay View Acceptance"), a Nevada corporation, as contributor (the
"Contributor") and BAY VIEW RECEIVABLES CORPORATION, a corporation established
under the laws of the State of Delaware, as depositor (the "Depositor").

                             PRELIMINARY STATEMENTS

            A.    The Contributor and Depositor are parties to that certain
Contribution Agreement dated as of June 5, 2003 (as the same may be amended,
restated, supplemented or otherwise modified the "Contribution Agreement").
Capitalized terms used herein and not otherwise defined shall have the meanings
ascribed to them in the Contribution Agreement.

            B.    The parties hereto have agreed to amend the Contribution
Agreement as set forth herein.

            NOW, THEREFORE, in consideration of the premises set forth above,
and other good and valuable consideration, the receipt and sufficiency of which
are hereby acknowledged, the parties hereto agree as follows:

            SECTION 1. Amendments to the Contribution Agreement. Effective as of
the date hereof and subject to the satisfaction of the conditions precedent set
forth in Section 2 below, the Contribution Agreement is hereby amended as
follows:

            1.1   Sections 3.02(a)(iii), (v) and (xiv) are hereby amended by
deleting the references therein to the "Soldiers' and Sailors' Civil Relief Act
of 1940" and replacing them with references to the "Servicemembers' Civil Relief
Act of 2003".

            1.2   Section 3.02(a)(xxv) of the Contribution Agreement is hereby
amended by restating subparagraphs (A), (B), (G), (H) and (I) thereof as
follows:

      (A)   no more than (i) 35% (determined by the Aggregate Receivable
      Balance) of all of the Receivables pledged to the Indenture Trustee, after
      taking into consideration the Subsequent Receivables pledged to the
      Indenture Trustee on such Funding Date, shall have been originated in
      California and (ii) 22% (determined by the Aggregate Receivable

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      Balance) of all of the Receivables pledged to the Indenture Trustee, after
      taking into consideration the Subsequent Receivables pledged to the
      Indenture Trustee on such Funding Date, shall have been originated in
      Texas;

      (B)   no more than 18% (determined by the Aggregate Receivable Balance) of
      all of the Receivables pledged to the Indenture Trustee, after taking into
      consideration the Subsequent Receivables pledged to the Indenture Trustee
      on such Funding Date, shall have been originated in any Core State other
      than California or Texas;

      (G)   no more than 35% (determined by the Aggregate Receivable Balance) of
      all of the Receivables pledged to the Indenture Trustee, after taking into
      consideration the Subsequent Receivables pledged to the Indenture Trustee
      on such Funding Date, shall have an original term of more than 84 months;

      (H)   no more than 85% (determined by the Aggregate Receivable Balance) of
      all of the Receivables pledged to the Indenture Trustee, after taking into
      consideration the Subsequent Receivables pledged to the Indenture Trustee
      on such Funding Date, shall have an original term of more than 72 months;

      (I)   no more than 65% (determined by the Aggregate Receivable Balance) of
      all of the Receivables pledged to the Indenture Trustee, after taking into
      consideration the Subsequent Receivables pledged to the Indenture Trustee
      on such Funding Date, shall have been, at the time of origination thereof,
      associated with a Financed Vehicle which is a used vehicle;

            1.3   Section 7.03 of the Contribution Agreement is hereby amended
by adding the following proviso at the end of the first sentence thereof:

            ; provided that, that no such amendment shall amend or modify any
      provision of Section 3.02(a) hereof without the consent of the
      Supermajority Holders.

            SECTION 2. Conditions Precedent. This Amendment shall become
effective as of the date first above written, upon receipt by each of the
Noteholders and the Agent of a copy of this Amendment duly executed by each of
the parties hereto and consented to by the Majority Holders as required by
Section 7.03 of the Contribution Agreement.

            SECTION 3. Covenants, Representations and Warranties of the
Contributor and Depositor.

            3.1   Upon the effectiveness of this Amendment, each of the
Contributor and Depositor hereby reaffirms all covenants, representations and
warranties made by it, as the same are amended hereby, in the Contribution
Agreement and agrees that all such covenants, representations and warranties
shall be deemed to have been re-made as of the effective date of this Amendment.

            3.2   Each of the Contributor and Depositor hereby represents and
warrants as to itself that this Amendment constitutes the legal, valid and
binding obligation of such party enforceable against such party in accordance
with its terms, except as enforceability may be

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limited by bankruptcy, insolvency, reorganization, moratorium or similar laws
affecting the enforcement of creditors' rights generally and general principles
of equity which may limit the availability of equitable remedies.

            SECTION 4. Reference to and Effect on the Contribution Agreement.

            4.1   Upon the effectiveness of this Amendment, each reference in
the Contribution Agreement to "this Agreement," "hereunder," "hereof," "herein,"
"hereby" or words of like import shall mean and be a reference to the
Contribution Agreement as amended hereby, and each reference to the Contribution
Agreement in any other document, instrument or agreement executed and/or
delivered in connection with the Contribution Agreement shall mean and be a
reference to the Contribution Agreement as amended hereby.

            4.2   Except as specifically amended hereby, the Contribution
Agreement and other documents, instruments and agreements executed and/or
delivered in connection therewith shall remain in full force and effect and are
hereby ratified and confirmed.

            4.3   The execution, delivery and effectiveness of this Amendment
shall not operate as a waiver of any right, power or remedy of the Depositor
under the Contribution Agreement or of the Indenture Trustee, the Agent or the
Noeholders under any of the other Transaction Documents, nor constitute a waiver
of any provision contained therein.

            SECTION 5. GOVERNING LAW. THIS AMENDMENT SHALL BE GOVERNED BY, AND
CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK (INCLUDING
SECTION 5-1401 OF THE GENERAL OBLIGATIONS LAWS BUT OTHERWISE WITHOUT REGARD TO
CONFLICTS OF LAW PRINCIPLES).

            SECTION 6. Execution in Counterparts. This Amendment may be executed
in any number of counterparts and by different parties hereto in separate
counterparts, each of which when so executed and delivered shall be deemed to be
an original and all of which taken together shall constitute but one and the
same instrument.

            SECTION 7. Headings. Section headings in this Amendment are included
herein for convenience of reference only and shall not constitute a part of this
Amendment for any other purpose.

            SECTION 8. Fees and Expenses. The Contributor hereby confirms its
agreement to pay on demand all reasonable costs and expenses of the parties
hereto and the parties requiring to consent hereto in connection with the
preparation, execution and delivery of this Amendment and any of the other
instruments, documents and agreements to be executed and/or delivered in
connection herewith, including, without limitation, the reasonable fees and
out-of-pocket expenses of counsel.

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IN WITNESS WHEREOF, the Contributor and the Depositor have caused this First
Amendment to Contribution Agreement to be duly executed by their respective
authorized officers as of the date and year first above written.

                                           BAY VIEW ACCEPTANCE CORPORATION, as
                                              Contributor

                                           By: /s/ John Okubo
                                               -------------------------------
                                               Name:  John Okubo
                                               Title: Chief Financial Officer

                                Signature Page to
                    Amendment No. 1 to Contribution Agreement

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                                           BAY VIEW RECEIVABLES CORPORATION, as
                                              Depositor

                                           By: /s/ John Okubo
                                               --------------------------------
                                               Name:  John Okubo
                                               Title: Chief Financial Officer

CONSENTED AND AGREED TO:

SHEFFIELD RECEIVABLES CORPORATION,
as Noteholder

By: BARCLAYS BANK PLC,
     as its attorney-in-fact

By  /s/ Janette Lieu
   ------------------------------------
    Name:  Janette Lieu
    Title: Director

BARCLAYS BANK PLC,
as Noteholder

By  /s/ Pierre Duleyrie
   ------------------------------------
    Name:  Pierre Duleyrie
    Title: Director

UBS REAL ESTATE SECURITIES INC.
as Noteholder

By  /s/ Shahid Quraishi
   ------------------------------------
    Name:  Shahid Quraishi
    Title: Managing Director

UBS REAL ESTATE SECURITIES INC.
as Noteholder

By  /s/ Tamer El-Rayess
   ------------------------------------
    Name:  Tamer El-Rayess
    Title: Director

                                Signature Page to
                    Amendment No. 1 to Contribution Agreement