Exhibit 10.6m

FOURTH AMENDMENT OF

FMC TECHNOLOGIES, INC. EMPLOYEES’ RETIREMENT PROGRAM

PART II UNION HOURLY EMPLOYEES’ RETIREMENT PLAN

WHEREAS, FMC Technologies, Inc. (the “Company”) maintains the FMC Technologies, Inc. Employees’ Retirement Program Part II Union Hourly Employees’ Retirement Plan (the “Plan”);

WHEREAS, amendment of the Plan is now considered desirable to (i) update the Plan’s definition of Actuarial Equivalent in furtherance of the final U.S. Treasury regulations regarding qualified joint and survivor annuity relative value requirements; (ii) reduce the cashout amount for Small Annuities with respect to Code Section 401(a)(31) and the related Department of Labor regulations regarding the administrative handling of Small Annuities; (iii) provide for retroactive annuity starting dates and (iv) increase the Benefit Rate with respect to Supplement 3, Smith Meter Plant, Erie, Pennsylvania; and

WHEREAS, this amendment shall supersede the provisions of the Plan to the extent those provisions are inconsistent with the provisions of the amendment;

NOW, THEREFORE, by virtue and in exercise of the powers reserved to the Company under Section 11.1 Plan Amendment or Termination of the Plan, the Plan is hereby amended in the following respects:

1. Effective February 1, 2006, the first paragraph of the definition of Actuarial Equivalent contained in Article I of the Plan is hereby amended and restated in its entirety to read as follows:

Actuarial Equivalent means a benefit determined to be of equal value to another benefit, on the basis of either (a) the UP-1984 Mortality Table and 8- ¹/2% interest compounded annually or (b) the mortality table and interest rate described in the applicable Supplement.

Notwithstanding the above to the contrary, for purposes of optional form of benefit conversions (including optional form of benefit conversions described in Supplements 2, 3, 4, 5 and 6, but excluding optional form of benefit conversions described in Supplement 1), Actuarial Equivalent means a benefit determined to be of equal value to another benefit on the basis of the greater of (1) either (a) the actuarial equivalent, computed using the UP-1984 Mortality Table and 8- ¹/2% interest compounded annually, of the accrued benefit as of February 1, 2006 or (b) the actuarial equivalent, computed using the mortality table and interest rate described in the applicable Supplement, of the accrued benefit as of February 1, 2006, or (2) the actuarial equivalent, computed using the RP-2000 Combined Healthy Participant Table (RP2000CH), weighted 80% male/20% female and 6% interest compounded annually, of the accrued benefit as of the date of determination on or after February 1, 2006.

2. Effective January 1, 2004, Section 6.3.2 is hereby amended by adding the following sentence to the end thereof to read as follows:

Notwithstanding the above to the contrary, effective January 1, 2004, in the event a Participant elects a Retroactive Annuity Starting Date as provided in Section 6.5, the notice under 6.3.1 shall be provided to the Participant on or about the date that the Participant files an election for a Retroactive Annuity Starting Date.

3. Effective January 1, 2004, Section 6.3.5 is hereby added to the Plan to read as follows:

Notwithstanding the foregoing provisions in Section 6.3, effective January 1, 2004, a Participant may elect a Retroactive Annuity Starting Date (as defined in Treas. Reg. 1.417(e)-1(b)(3)(iv)(B)), pursuant to Section 6.5. In the event that the notice information described in Section 6.3 is provided to the Participant after the Participant’s Annuity Starting Date (as defined in Section 417(f)(2) of the Code) or Retroactive Annuity Starting Date, the Participant shall have at least 30 days after the date the notification is provided to make the election described in Section 6.3. The Participant may waive this 30 day period pursuant to the provisions of Section 6.3.4.

4. Effective January 1, 2004, Section 6.5 is hereby added to the Plan to read as follows:

6.5. Election of Retroactive Annuity Starting Date Effective January 1, 2004, a Participant may elect a “Retroactive Annuity Starting Date” (as defined in Treas. Reg. 1.417(e)-l(b)(3)(iv)(B)), that occurs on or before the date the notice information described in Section 6.3 is provided to the Participant, provided the following conditions are satisfied:

If a Participant elects a Retroactive Annuity Starting Date the following provisions shall apply:

5. Effective for distributions made on or after January 1, 2005, the first paragraph of Section 12.8 contained in Article XII of the Plan is hereby amended and restated in its entirety to read as follows:

If the sum of (a) the lump sum Actuarial Equivalent value of a Normal, Early, or Deferred Retirement Benefit under Article III, Termination Benefit (payable at the Participant’s Normal Retirement Date) under Article IV or Survivor’s Benefit under Article VII, excluding any Aetna or Prudential nonparticipating annuity; and (b) the lump sum Actuarial Equivalent value of any Aetna or Prudential nonparticipating annuity is equal to $1,000 (or such other amount as may be prescribed in or under the Code) or less, such amounts shall be paid in a lump sum as soon as administratively practicable following the Participant’s retirement, termination of employment or death.

6. Effective September 1, 2005, Section 1-7 of Supplement 1 – Jetway Systems Division – Ogden, Utah is hereby amended in its entirety to read as follows:

Early Retirement Date means the later of the Participant’s 55^th birthday and the date the Participant acquires 10 years of Credited Service.

7. Effective September 1, 2005, the table of early retirement reduction factors set forth in Section 1-8 of Supplement 1 – Jetway Systems Division – Ogden, Utah is hereby deleted in its entirety and replaced with the following table:

8. Effective January 1, 2006, the chart that appears in Section 3-5 Normal Retirement Benefit of Supplement 3 - Smith Meter Plant, Erie, Pennsylvania is hereby amended in its entirety to read as follows:

A Participant’s monthly Normal Retirement Benefit shall be determined by multiplying the fixed rate provided below in effect on the date the Participant’s Years of Credited Service terminate, multiplied by the Participant’s Years of Credited Service:

IN WITNESS WHEREOF, the Company has caused this amendment to be executed by a duly authorized representative this 24^TH day of OCTOBER, 2006.