<PAGE>

                                                                     Exhibit 4.6


                         RESTATED DECLARATION OF TRUST
                         -----------------------------

          THIS RESTATED DECLARATION OF TRUST is dated as of October 13, 2000,
between Devon Energy Corporation, an Oklahoma corporation, as sponsor (the
"Sponsor"), and J. M. Lacey, Darryl G. Smette, William T. Vaughn, The Bank of
New York, a New York banking corporation, and The Bank of New York (Delaware), a
Delaware banking corporation, not in their individual capacities but solely as
trustees (collectively the "Trustees" and each individually "Trustee").  The
Sponsor and the Trustees hereby agree as follows:

          1.  The trust created hereby (the "Trust") shall be known as "Devon
Financing Trust II," 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 Trustees the sum of $10. The Trustees hereby acknowledge receipt of such
amount in trust from the Sponsor, which amount shall constitute the initial
trust estate. The Trustees hereby declare that they will hold the trust estate
in trust 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. (S) 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 with the Delaware Secretary of State in the form attached hereto.

          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 (the "Preferred Securities") and the common securities (the
"Common Securities") referred to herein. 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 of the trust estate, except as
otherwise contemplated by this Restated Declaration of Trust, 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. Notwithstanding the foregoing, the Trustees may take all actions
deemed proper as are necessary to effect the transactions contemplated herein.

          The Sponsor and the Trustees hereby authorize and direct the Sponsor,
as the Sponsor of the Trust, (1) to prepare and file with the Securities and
Exchange Commission (the "Commission") and to execute, in the case of the 1933
Act Registration Statement and the 1934 Act Registration Statement (as herein
defined), on behalf of the Trust, (a) a Registration Statement (the "1933 Act
Registration Statement"), including all pre-effective and post-effective
amendments thereto, relating to the registration under the Securities Act of
1933, as amended (the "1933 Act"), of the trust preferred securities of the
Trust, (b) any preliminary prospectus or prospectus supplement thereto relating
to the trust preferred securities of the Trust required to be filed pursuant to
the 1933 Act, and (c) if and at such time as determined by the Sponsor, a
Registration Statement on Form 8-A or other appropriate form (the "1934 Act
Registration Statement"), including all pre-effective and post-effective
amendments thereto, relating to the registration of the trust preferred
securities of the Trust under the Securities Exchange Act of
<PAGE>

1934, as amended; (2) if and at such time as determined by the Sponsor, to file
with the American Stock Exchange or other exchange, or the National Association
of Securities Dealers ("NASD"), and execute on behalf of the Trust a listing
application and all other applications, statements, certificates, agreements and
other instruments as shall be necessary or desirable to cause the trust
preferred securities of the Trust to be listed on the American Stock Exchange or
other such exchange, or the NASD's Nasdaq National Market; (3) 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 the trust
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; (4) to execute and deliver letters or documents to, or instruments
for filing with, a depository relating to the trust preferred securities of the
Trust; and (5) to execute, deliver and perform on behalf of the trust an
underwriting agreement with one or more underwriters relating to the offering of
the trust preferred securities of the Trust. In the event that any filing
referred to in this Section 4 is required by the rules and regulations of the
Commission, the American Stock Exchange or other exchange, NASD, or state
securities or "blue sky" laws to be executed on behalf of the Trust by the
Trustees, J. M. Lacey, Darryl G. Smette and William T. Vaughn, in their capacity
as trustees of the Trust, are hereby authorized to join in any such filing and
to execute on behalf of the Trust any and all of the foregoing, it being
understood that each of such Trustees, in his capacity as a trustee of the
Trust, shall not be required to join in any such filing or execute on behalf of
the Trust any such document unless such Trustee is required to do so by the
rules and regulations of the Commission, the American Stock Exchange or other
exchange, NASD, or state securities or "blue sky" laws.

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

          5.  The number of Trustees initially shall be five (5) 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 five (5); and provided, further 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 which
has its principal place of business in the State of Delaware and otherwise meets
the requirements of applicable law.  Subject to the foregoing, the Sponsor is
entitled to appoint or remove without cause any Trustee at any time.  The
Trustees may resign upon thirty days prior notice to the Sponsor.

                                      -2-
<PAGE>

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

                                 DEVON ENERGY CORPORATION, an Oklahoma
                                 corporation

                                 By: /s/ J. Larry Nichols
                                    --------------------------------------
                                    J. Larry Nichols, President and Chief
                                    Executive Officer

                                                                       "SPONSOR"

                                 THE BANK OF NEW YORK, a New York banking
                                 corporation

                                 By:  /s/ Van K. Brown
                                     ---------------------------------------
                                     Name: Van K. Brown
                                     Title: Vice President

                                 THE BANK OF NEW YORK (DELAWARE), a Delaware
                                 banking corporation

                                 By:  /s/ Michael Santino
                                    --------------------------------------
                                    Name: Michael Santino
                                    Title: Senior Vice President

                                 /s/ J. M. Lacey
                                 -----------------------------------------
                                 J. M. Lacey

                                 /s/ Darryl G. Smette
                                 -----------------------------------------
                                 Darryl G. Smette

                                 /s/ William T. Vaughn
                                 -----------------------------------------
                                 William T. Vaughn

                                                                      "TRUSTEES"

                                      -3-
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                                   EXHIBIT A

                             CERTIFICATE OF TRUST
                             --------------------

                                      OF
                                      --

                           DEVON FINANCING TRUST II
                           ------------------------

          1.  The name of the business trust is:

                           DEVON FINANCING TRUST II

          2.  The name and business address of the trustee having its principal
place of business in the State of Delaware are:

              The Bank of New York (Delaware)
              White Clay Center
              Route 273
              Newark, Delaware  19711

          3.  This Certificate shall be effective upon the filing hereof.

          Executed this 13th day of October, 2000.

                                 THE BANK OF NEW YORK, a New York banking
                                 corporation

                                 By: /s/ Van K. Brown
                                    --------------------------------------
                                    Name: Van K. Brown
                                    Title: Vice President

                                 THE BANK OF NEW YORK (DELAWARE), a Delaware
                                 banking corporation

                                 By: /s/ Michael Santino
                                    --------------------------------------
                                    Name: Michael Santino
                                    Title: Senior Vice President

                                 /s/ J. M. Lacey
                                 -----------------------------------------
                                 J. M. Lacey

                                 /s/ Darryl G. Smette
                                 -----------------------------------------
                                 Darryl G. Smette

                                 /s/ William T. Vaughn
                                 -----------------------------------------
                                 William T. Vaughn

                                      -4-