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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