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                                                                    EXHIBIT 4.20

                              DECLARATION OF TRUST


                  DECLARATION OF TRUST, dated as of November 16, 2001, between
BorgWarner Inc., as sponsor (the "Sponsor"), Bank One Delaware, Inc., as
Delaware trustee (the "Delaware Trustee"), and Jeffrey L. Obermayer, Margaret E.
Annett and Dennis Krol, as administrative trustees (the "Administrative
Trustees" and collectively with the Delaware Trustee, the "Trustees"). The
Sponsor and the Trustees hereby agree as follows:

                  1. The trust created hereby (the "Trust") shall be known as
"BorgWarner Capital Trust I", in which name the Trustees, or the Sponsor to the
extent provided herein, may conduct the business of the Trust, make and execute
contracts, and sue and be sued.

                  2. The Sponsor hereby assigns, transfers, conveys and sets
over to the Trust the sum of $10. The Trustees hereby acknowledge receipt of
such amount from the Sponsor, which amount shall constitute the initial trust
estate. The Trustees hereby declare that they will hold the trust estate for the
Sponsor. It is the intention of the parties hereto that the Trust created hereby
constitute a business trust under Chapter 38 of Title 12 of the Delaware Code,
12 Del. C. ss.ss. 3801 et seq. (the "Business Trust Act"), and that this
document constitute the governing instrument of the Trust. The Trustees are
hereby authorized and directed to execute and file a certificate of trust in the
office of the Secretary of State of the State of Delaware in the form attached
hereto. The Trust is hereby established by the Sponsor and the Trustees for the
purposes of (i) issuing preferred securities ("Preferred Securities")
representing undivided beneficial interests in the assets of the Trust in
exchange for cash and investing the proceeds thereof in debt securities of the
Sponsor, (ii) issuing and selling common securities ("Common Securities")
representing undivided beneficial interests in the assets of the Trust to the
Sponsor in exchange for cash and investing the proceeds thereof in additional
debt securities of the Sponsor and (iii) engaging in such other activities as
are necessary, convenient or incidental thereto.

                  3. The Sponsor and the Trustees will enter into an amended and
restated Declaration of Trust, satisfactory to each such party, to provide for
the contemplated operation of the Trust created hereby and the issuance of the
Preferred Securities and the Common Securities referred to therein. Prior to the
execution and delivery of such amended and restated Declaration of Trust, the
Trustees shall not have any duty or obligation hereunder or with respect to the
trust estate, except as otherwise required by applicable law or as may be
necessary to obtain, prior to such execution and delivery, any licenses,
consents or approvals required by applicable law or otherwise.

                  4. The Sponsor and the Trustees hereby authorize and direct
the Sponsor, as the sponsor of the Trust, (i) to prepare and file a Registration
Statement (including the Prospectus included therein and any Prospectus
Supplement relating thereto) relating to the Preferred Securities meeting the
requirements of the Securities Act of 1933, as amended (the "1933 Act"), and
such other forms or filings as may be required by the 1933 Act, the Securities
Exchange Act of 1934, as amended, or the Trust Indenture Act of 1939, as
amended, in each case relating to the Preferred Securities of the Trust; (ii) to
file and execute on behalf of the Trust, such applications, reports, surety
bonds, irrevocable consents, appointments of attorney for service of process and
other papers and documents that shall be necessary or desirable to register or
establish the



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exemption from registration of the Preferred Securities of the Trust under the
securities or blue sky laws of such jurisdictions as the Sponsor, on behalf of
the Trust, may deem necessary or desirable; (iii) to execute and file an
application, and all other applications, statements, certificates, agreements
and other instruments that shall be necessary or desirable, to the New York
Stock Exchange or any other national stock exchange or the Nasdaq National
Market for listing or quotation of the Preferred Securities of the Trust; (iv)
to execute and deliver letters or documents to, or instruments for filing with,
a depository relating to the Preferred Securities of the Trust; and (v) to
execute, deliver and perform on behalf of the Trust one or more underwriting
agreements, purchase agreements, dealer manager agreements, escrow agreements
and other related agreements providing for or relating to the sale of the
Preferred Securities of the Trust. It is hereby acknowledged and agreed that in
connection with any execution or filing of any document referred to in clauses
(i)-(iii) above, (A) any Administrative Trustee (or his attorneys-in-fact and
agents or the Sponsor as permitted herein) is authorized on behalf of the Trust
to file and execute such document on behalf of the Trust and (B) the Delaware
Trustee shall not be required to join in any such filing or execute on behalf of
the Trust any such document unless required by the rules and regulations of the
New York Stock Exchange or any other national stock exchange or the Nasdaq
National Market or state securities or blue sky laws, and in such case only to
the extent so required.

                  5. This Declaration of Trust may be executed in one or more
counterparts.

                  6. The number of Trustees initially shall be four (4) and
thereafter the number of Trustees shall be such number as shall be fixed from
time to time by a written instrument signed by the Sponsor which may increase or
decrease the number of Trustees; provided, however, that the number of Trustees
shall in no event be less than four (4); and provided, further, however, that to
the extent required by the Business Trust Act, one Trustee shall either be a
natural person who is a resident of the State of Delaware or, if not a natural
person, an entity that has its principal place of business in the State of
Delaware and meets any other requirements imposed by applicable law. Subject to
the foregoing, the Sponsor is entitled to appoint or remove without cause any
Trustee at any time. Any Trustee may resign upon 30 days prior notice to the
Sponsor; provided, however, that the Delaware Trustee may resign immediately
upon notice to the Sponsor if the Delaware Trustee is required to join in any
filing or execute on behalf of the Trust any document pursuant to the provisions
of paragraph 4 hereof and, upon giving such notice, the Delaware Trustee shall
not be required to join in any such filing or execute on behalf of the Trust any
such document; provided, further, however, that no resignation of the Delaware
Trustee shall be effective until a successor Delaware Trustee has been appointed
and has accepted such appointment by instrument executed by such successor
Delaware Trustee and delivered to the Trust, the Sponsor and the resigning
Delaware Trustee.

                  7. To the fullest extent permitted by applicable law, the
Sponsor agrees to indemnify (i) the Delaware Trustee, (ii) any affiliate of the
Delaware Trustee, and (iii) any officers, directors, shareholders, members,
partners, employees, representatives, nominees, custodians or agents of the
Delaware Trustee (each of the persons or entities in (i) through (iii) being
referred to as an "Indemnified Person") for, and to hold each Indemnified Person
harmless against, any loss, liability or expense incurred without negligence or
bad faith on its part, arising out of or in connection with the acceptance or
administration of the trust or trusts hereunder, including the costs and
expenses (including reasonable legal fees and expenses) of defending


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itself against, or investigating, any claim or liability in connection with the
exercise or performance of any of its powers or duties hereunder. The obligation
to indemnify as set forth in this paragraph 7 shall survive the termination of
this Declaration. The Delaware Trustee shall not have any of the powers or
duties of the trustees set forth herein, except as required under the Business
Trust Act. The Delaware Trustee shall be a trustee hereunder for the sole and
limited purpose of fulfilling the requirements of Section 3807(a) of the
Business Trust Act.

                  8. The Trust may terminate without issuing any Trust
Securities at the election of the Sponsor.

                  9. This Declaration shall be governed by the laws of the State
of Delaware, without regard to conflict of laws principles.




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                  IN WITNESS WHEREOF, the parties hereto have caused this
Declaration of Trust to be duly executed as of the day and year first above
written.


                                         BORGWARNER INC.,
                                         as Sponsor



                                         By: /s/ JEFFREY L. OBERMAYER
                                             -----------------------------------
                                             Name: Jeffrey L. Obermayer
                                             Title: Vice President and Treasurer


                                         BANK ONE DELAWARE, INC.,
                                         as Delaware Trustee



                                         By: /s/ MARLA S. ROTH
                                             -----------------------------------
                                              Name: Marla S. Roth
                                              Title: Vice President




                                         /s/ JEFFREY L. OBERMAYER
                                         ---------------------------------------
                                         Jeffrey L. Obermayer, as Trustee



                                         /s/ MARGARET E. ANNETT
                                         ---------------------------------------
                                         Margaret E. Annett, as Trustee



                                         /s/ DENNIS KROL
                                         ---------------------------------------
                                         Dennis Krol, as Trustee








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