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                                                                    EXHIBIT 10.6

                          INCOME TAX SHARING AGREEMENT

               THIS INCOME TAX SHARING AGREEMENT ("Agreement"), made this 10th
day of April 2001, by and among DEG Acquisitions, LLC, a Delaware limited
liability company ("Holdings") and Dresser, Inc., a Delaware corporation
("Dresser").

               WHEREAS, Dresser is a wholly-owned subsidiary of Holdings;

               WHEREAS, Holdings and Dresser are members of an affiliated group
of corporations within the meaning of Section 1504(a) of the Internal Revenue
Code of 1986, as amended (the "Code"), of which Holdings is the common parent
corporation (the "DEG Group"); and

               WHEREAS, Holdings and Dresser desire to provide for the sharing
and allocation of income taxes in accordance with this Agreement.

               NOW, THEREFORE, in consideration of the mutual covenants
contained herein, the parties hereto agree as follows:

               1. Filing of Returns.

               Dresser, on behalf of itself and each of its subsidiaries,
consents to the filing by Holdings of consolidated federal income tax returns
for all taxable periods in which it is eligible to be a member of the DEG Group.
Holdings agrees to file such consents, elections, tax returns and other
documents, and to take such other actions as may be necessary or appropriate to
file a consolidated federal income tax return for each taxable period for which
the DEG Group is required or permitted to file a consolidated federal income tax
return. Any taxable period ending after the date of this Agreement for which
Dresser is included in a consolidated federal income tax return filed by the DEG
Group is referred to herein as a "Consolidated Return Year."

               2. Sharing and Settlement of U.S. Federal Consolidated Income
Taxes.

               For all relevant taxable periods, Holdings shall calculate the
consolidated federal income tax liability (including, if applicable, alternative
minimum tax liability) of the DEG Group for such period (the "Group Liability").
If (a) the Group Liability exceeds (b) the corresponding consolidated federal
income tax liability for such period that Holdings would have incurred if
Dresser and its subsidiaries had not been members of the DEG Group, Dresser
shall pay the amount of such excess to Holdings.

               3. State, Local or Foreign Income Taxes. In the event Holdings
files combined, unitary or consolidated state, local or foreign income tax
returns with Dresser and any of its subsidiaries, the provisions of Sections 1
and 2 hereof shall be applicable as if such combined, unitary or consolidated
income tax returns filed were consolidated federal income tax returns.

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               4. No Other Tax Sharing Obligations. No tax sharing obligations
between the parties to this Agreement shall arise out of any taxes other than
those taxes referred to in Sections 2 and 3 hereof.

               5. Subsequent Return Adjustments.

               In applying the "with and without" calculation referenced in
Section 2 above, the appropriate frame of reference shall be all tax years in
which a consolidated tax return was or is filed.

               In the event a consolidated federal income tax return or any
combined, unitary or consolidated state, local or foreign income tax return is
amended or adjusted (whether by reason of the filing of an amended return, a
claim for refund, or otherwise), the tax liabilities and benefits of Holdings
and Dresser will be redetermined, adjusted and settled on a basis consistent
with the above provisions.

               In the event the federal consolidated tax liability or any
combined, unitary or consolidated state, local or foreign income tax liability
is redetermined or adjusted pursuant to an audit or challenge by a taxing
authority, or if a voluntary tax payment is made to limit the accrual of
interest on audit issues, the liability of Holdings and Dresser will be
redetermined by Holdings in its sole discretion, exercised in good faith.
Payments reflecting such redeterminations or adjustments shall be made when (a)
a settlement (evidenced in writing or by the payment of taxes) is entered into
with the taxing authority, (b) a decision of a court having jurisdiction in the
matter becomes final and is not subject to appeal, or (c) Holdings makes a
voluntary tax payment with respect to a consolidated federal income tax return
or any combined, unitary or consolidated state, local or foreign income tax
return.

               6. Penalties and Interest.

               If penalties or interest are imposed by the taxing authorities,
or if a voluntary interest payment is made, such payment will be allocated to
and made by each responsible corporation. If any interest from the taxing
authorities is received by any corporation included in the consolidated returns
of DEG Group, such interest shall be allocated by Holdings in its sole
discretion, exercised in good faith, and refunded to the attributable
corporation.

               7. Billing.

               All cash settlements of cash liabilities shall take place between
Holdings and Dresser at least ten (10) days prior to the date the related taxes
are payable, whether for estimated taxes or otherwise, and upon execution of
this Agreement for taxes due prior to the date of this Agreement ("Execution
Payment"). Late payments (if any) shall bear an annual rate of interest equal to
the statutory rate of interest for the underpayment of taxes then in effect from
the date such payments are due.

               8. Procedural Matters.

               So long as any party to this Agreement remains part of the DEG
Group for federal income tax purposes, Holdings will prepare and file the
consolidated returns, along with any

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other documents or statements that are required to be filed with the taxing
authorities for U.S. federal income tax purposes related to consolidated
returns. The parties hereto acknowledge that, with respect to consolidated tax
returns which they have filed or will file, Holdings has the right, in its sole
discretion, to:

               (a) determine:

                    (i) the manner in which such returns, documents or
               statements are prepared and filed including, without limitation,
               the manner in which any item of income gain, loss, deduction or
               credit shall be reported;

                    (ii) the manner in which the consolidated tax liability will
               be allocated for the purpose of determining the taxable earnings
               and profits of each corporation;

                    (iii) whether any extensions may be requested; and

                    (iv) the elections that are made by any corporation included
               in DEG Group's consolidated returns;

               (b) contest, compromise or settle any adjustment or deficiency
          proposed, asserted or assessed as a result of any audit of such
          returns by the taxing authorities;

               (c) file, prosecute, compromise or settle any claim for refund;
          and

               (d) determine whether any refunds to which Holdings or its
          subsidiaries may be entitled are paid by way of refund or credited
          against the tax liability of DEG Group.

               Without limiting its rights and obligations, Dresser hereby
irrevocably appoints Holdings as its agent and attorney-in-fact to take such
action (including the execution of documents) as Holdings may deem appropriate
to effect the foregoing.

               9. Miscellaneous Provisions.

               (a) Notices. Notices and other communications with respect to
this Agreement shall be in writing and shall be delivered by hand or overnight
courier service, or sent by telecopy. Unless other addresses or telecopy numbers
are specified in writing pursuant to this Section 9(a) to each party to this
Agreement, such notices or other communications shall be sent to the following
addresses or telecopy numbers, as the case may be:

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                    (i)      if to Holdings, to it at:

                             DEG Acquisitions, LLC
                             c/o First Reserve Corporation
                             411 West Putnam Ave., Suite 109
                             Greenwich, CT  06830
                             Attn.: Thomas R. Denison
                             Telephone: (303) 382-1271
                             Telecopy: (303) 382-1275

                    (ii)     if to Dresser, to it at:

                             Dresser, Inc.
                             2601 Beltline Road
                             Carollton, Texas 75006
                             Attn.: Dale Mikus
                             Telephone: (972) 478-5090
                             Telecopy: (972) 478-5088

               (b) Binding Effect. This Agreement shall be binding upon and
inure to the benefit of the parties hereto and their respective successors and
permitted assigns. Each of Holdings and Intermediate Holdings shall cause their
respective affiliates to carry out any obligation of such affiliate specified
herein.

               (c) Governing Law. The parties hereto hereby agree that this
Agreement shall be construed in accordance with and governed by the laws of the
State of New York, without regard to any other applicable conflict of law
provision.

               (d) Waivers; Amendment; Modification. Neither this Agreement nor
any provision hereof may be waived, amended or modified, except pursuant to an
agreement or agreements in writing entered into by all the parties hereto.

               (e) Entire Agreement. This Agreement constitutes the entire
agreement among the parties hereto with respect to the subject matter hereof.

               (f) Severability. In the event any one or more of the provisions
contained in this Agreement should be held invalid, illegal or unenforceable in
any respect, the validity, legality and enforceability of the remaining
provisions contained herein shall not in any way be affected or impaired
thereby.

               (g) Counterparts. This Agreement may be executed in two or more
counterparts, each of which shall constitute an original but all of which, when
taken together, shall constitute but one contract.

               (h) Further Actions. The parties will execute and deliver such
further instruments and do such further acts and things (including, without
limitation, by causing their subsidiaries, if any, to do such acts and things)
as may be required to carry out the intent and purposes of this Agreement.

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          IN WITNESS WHEREOF, the undersigned parties have caused this Agreement
to be executed as of the date first above written.


                                  DEG ACQUISITIONS, LLC

                                  FIRST RESERVE FUND VIII, L.P.,
                                    a Delaware limited partnership, its manager
                                      By: First Reserve GP VIII, L.P.
                                           a Delaware limited partnership, its
                                           general partner
                                          By: First Reserve Corporation,
                                               a Delaware corporation, its
                                               general partner


                                                    By: /s/ THOMAS R. DENISON
                                                       -------------------------
                                                       Name: Thomas R. Denison
                                                       Title: Managing Director


                                        DRESSER, INC.


                                        By: /s/ FRANK P. PITTMAN
                                           -------------------------------------
                                           Name:  Frank P. Pittman
                                           Title: Vice President