=============================================================================
                                 UNITED STATES
                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C.  20549
                                 SCHEDULE 13D
                Under the Securities and Exchange Act of 1934

                               (Amendment No. 6)

                            Trinity Industries, Inc.
               ------------------------------------------------
                               (Name of Issuer)

                                 Common Stock
                ------------------------------------------------
                        (Title of Class of Securities)

                                  896522109
                ------------------------------------------------
                               (CUSIP Number)

                           Allison Bennington, Esq.
                              ValueAct Capital
                 One Letterman Drive, Building D, Fourth Floor
                          San Francisco, CA  94129
                               (415) 362-3700
                ------------------------------------------------
                 (Name, address and telephone number of Person
                Authorized to Receive Notices and Communications)


                               March 15, 2018
                ------------------------------------------------
             (Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report
the acquisition that is the subject of this Schedule 13D, and is filing this
schedule because of 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the
following box [ ].

Note:  Schedules filed in paper format shall include a signed original and five
copies of the schedule, including all exhibits. See Rule 240.13d-7 for other
parties to whom copies are to be sent.

*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities,
and for any subsequent amendment containing information which would alter
disclosures provided in a prior cover page.

This information required on the remainder of this cover page shall not be
deemed to be "filed" for the purpose of Section 18 of the Securities Exchange
Act of 1934 ("Act") or otherwise subject to the liabilities of that section of
the Act but shall be subject to all other provisions of the Act (however, see
the Notes).
=============================================================================


                                SCHEDULE 13D
--------------------------                          -------------------------
CUSIP NO. 896522109                                             Page 2 of 11
-----------------------------------------------------------------------------
1. NAME OF REPORTING PERSON/S.S. OR I.R.S. INDENTIFICATION NO. OF ABOVE
   PERSON (entities only)

   ValueAct Capital Master Fund, L.P.
-----------------------------------------------------------------------------
2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                  (a) [X]
                                                                      (b) [ ]
-----------------------------------------------------------------------------
3. SEC USE ONLY

-----------------------------------------------------------------------------
4. SOURCE OF FUNDS (See Instructions)*

   WC*
-----------------------------------------------------------------------------
5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
   PURSUANT TO ITEMS 2(d) or 2(e)                                         [ ]
-----------------------------------------------------------------------------
6. CITIZENSHIP OR PLACE OF ORGANIZATION

   British Virgin Islands
-----------------------------------------------------------------------------
                    7.  SOLE VOTING POWER
                        0
   NUMBER OF       ----------------------------------------------------------
   SHARES           8.  SHARED VOTING POWER
   BENEFICIALLY         20,763,695**
   OWNED BY EACH   ----------------------------------------------------------
   PERSON WITH      9.  SOLE DISPOSITIVE POWER
                        0
                   ----------------------------------------------------------
                   10.  SHARED DISPOSITIVE POWER
                        20,763,695**
-----------------------------------------------------------------------------
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

    20,763,695**
-----------------------------------------------------------------------------
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
    CERTAIN SHARES                                                        [ ]
-----------------------------------------------------------------------------
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

    13.8%
-----------------------------------------------------------------------------
14. TYPE OF REPORTING PERSON

    PN
-----------------------------------------------------------------------------
*See Item 3
**See Item 2 and 5




                                SCHEDULE 13D
--------------------------                          -------------------------
CUSIP NO. 896522109                                             Page 3 of 11
----------------------------------------------------------------------------
1. NAME OF REPORTING PERSON/S.S. OR I.R.S. INDENTIFICATION NO. OF ABOVE
   PERSON (entities only)

   VA Partners I, LLC
-----------------------------------------------------------------------------
2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                  (a) [X]
                                                                      (b) [ ]
-----------------------------------------------------------------------------
3. SEC USE ONLY

-----------------------------------------------------------------------------
4. SOURCE OF FUNDS*

   00*
-----------------------------------------------------------------------------
5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
   PURSUANT TO ITEMS 2(d) or 2(e)                                         [ ]
-----------------------------------------------------------------------------
6. CITIZENSHIP OR PLACE OF ORGANIZATION

   Delaware
-----------------------------------------------------------------------------
                    7.  SOLE VOTING POWER
                        0
   NUMBER OF       ----------------------------------------------------------
   SHARES           8.  SHARED VOTING POWER
   BENEFICIALLY         20,763,695**
   OWNED BY EACH   ----------------------------------------------------------
   PERSON WITH      9.  SOLE DISPOSITIVE POWER
                        0
                   ----------------------------------------------------------
                   10.  SHARED DISPOSITIVE POWER
                        20,763,695**
-----------------------------------------------------------------------------
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

    20,763,695**
-----------------------------------------------------------------------------
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
    CERTAIN SHARES                                                        [ ]
-----------------------------------------------------------------------------
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

    13.8%
-----------------------------------------------------------------------------
14. TYPE OF REPORTING PERSON

    00 (LLC)
-----------------------------------------------------------------------------
*See Item 3
**See Item 2 and 5


                                SCHEDULE 13D
--------------------------                          -------------------------
CUSIP NO. 896522109                                             Page 4 of 11
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1. NAME OF REPORTING PERSON/S.S. OR I.R.S. INDENTIFICATION NO. OF ABOVE
   PERSON (entities only)

   ValueAct Capital Management, L.P.
-----------------------------------------------------------------------------
2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                  (a) [X]
                                                                      (b) [ ]
-----------------------------------------------------------------------------
3. SEC USE ONLY

-----------------------------------------------------------------------------
4. SOURCE OF FUNDS*

   00*
-----------------------------------------------------------------------------
5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
   PURSUANT TO ITEMS 2(d) or 2(e)                                         [ ]
-----------------------------------------------------------------------------
6. CITIZENSHIP OR PLACE OF ORGANIZATION

   Delaware
-----------------------------------------------------------------------------
                    7.  SOLE VOTING POWER
                        0
   NUMBER OF       ----------------------------------------------------------
   SHARES           8.  SHARED VOTING POWER
   BENEFICIALLY         20,763,695**
   OWNED BY EACH   ----------------------------------------------------------
   PERSON WITH      9.  SOLE DISPOSITIVE POWER
                        0
                   ----------------------------------------------------------
                   10.  SHARED DISPOSITIVE POWER
                        20,763,695**
-----------------------------------------------------------------------------
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

    20,763,695**
-----------------------------------------------------------------------------
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
    CERTAIN SHARES                                                        [ ]
-----------------------------------------------------------------------------
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

    13.8%
-----------------------------------------------------------------------------
14. TYPE OF REPORTING PERSON

    PN
-----------------------------------------------------------------------------
*See Item 3
**See Item 2 and 5


                                SCHEDULE 13D
--------------------------                          -------------------------
CUSIP NO. 896522109                                             Page 5 of 11
----------------------------------------------------------------------------
1. NAME OF REPORTING PERSON/S.S. OR I.R.S. INDENTIFICATION NO. OF ABOVE
   PERSON (entities only)

   ValueAct Capital Management, LLC
-----------------------------------------------------------------------------
2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                  (a) [X]
                                                                      (b) [ ]
-----------------------------------------------------------------------------
3. SEC USE ONLY

-----------------------------------------------------------------------------
4. SOURCE OF FUNDS*

   00*
-----------------------------------------------------------------------------
5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
   PURSUANT TO ITEMS 2(d) or 2(e)                                         [ ]
-----------------------------------------------------------------------------
6. CITIZENSHIP OR PLACE OF ORGANIZATION

   Delaware
-----------------------------------------------------------------------------
                    7.  SOLE VOTING POWER
                        0
   NUMBER OF       ----------------------------------------------------------
   SHARES           8.  SHARED VOTING POWER
   BENEFICIALLY         20,763,695**
   OWNED BY EACH   ----------------------------------------------------------
   PERSON WITH      9.  SOLE DISPOSITIVE POWER
                        0
                   ----------------------------------------------------------
                   10.  SHARED DISPOSITIVE POWER
                        20,763,695**
-----------------------------------------------------------------------------
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

    20,763,695**
-----------------------------------------------------------------------------
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
    CERTAIN SHARES                                                        [ ]
-----------------------------------------------------------------------------
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

    13.8%
-----------------------------------------------------------------------------
14. TYPE OF REPORTING PERSON

    00 (LLC)
-----------------------------------------------------------------------------
*See Item 3
**See Item 2 and 5


                                SCHEDULE 13D
--------------------------                          -------------------------
CUSIP NO. 896522109                                             Page 6 of 11
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1. NAME OF REPORTING PERSON/S.S. OR I.R.S. INDENTIFICATION NO. OF ABOVE
   PERSON (entities only)

   ValueAct Holdings, L.P.
---------------------------------------------------------------------------
2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                  (a) [X]
                                                                      (b) [ ]
-----------------------------------------------------------------------------
3. SEC USE ONLY

---------------------------------------------------------------------------
4. SOURCE OF FUNDS*

   00*
-----------------------------------------------------------------------------
5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
   PURSUANT TO ITEMS 2(d) or 2(e)                                         [ ]
-----------------------------------------------------------------------------
6. CITIZENSHIP OR PLACE OF ORGANIZATION

   Delaware
-----------------------------------------------------------------------------
                    7.  SOLE VOTING POWER
                        0
   NUMBER OF       ----------------------------------------------------------
   SHARES           8.  SHARED VOTING POWER
   BENEFICIALLY         20,763,695**
   OWNED BY EACH   ----------------------------------------------------------
   PERSON WITH      9.  SOLE DISPOSITIVE POWER
                        0
                   ----------------------------------------------------------
                   10.  SHARED DISPOSITIVE POWER
                        20,763,695**
-----------------------------------------------------------------------------
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

    20,763,695**
-----------------------------------------------------------------------------
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
    CERTAIN SHARES                                                        [ ]
-----------------------------------------------------------------------------
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

    13.8%
-----------------------------------------------------------------------------
14. TYPE OF REPORTING PERSON

    PN
-----------------------------------------------------------------------------
*See Item 3
**See Items 2 and 5


                                SCHEDULE 13D
--------------------------                          -------------------------
CUSIP NO. 896522109                                             Page 7 of 11
-----------------------------------------------------------------------------
1. NAME OF REPORTING PERSON/S.S. OR I.R.S. INDENTIFICATION NO. OF ABOVE
   PERSON (entities only)

   ValueAct Holdings GP, LLC
---------------------------------------------------------------------------
2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                  (a) [X]
                                                                      (b) [ ]
-----------------------------------------------------------------------------
3. SEC USE ONLY

-----------------------------------------------------------------------------
4. SOURCE OF FUNDS*

   00*
-----------------------------------------------------------------------------
5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
   PURSUANT TO ITEMS 2(d) or 2(e)                                        [ ]
-----------------------------------------------------------------------------
6. CITIZENSHIP OR PLACE OF ORGANIZATION

   Delaware
-----------------------------------------------------------------------------
                   7.  SOLE VOTING POWER
                        0
   NUMBER OF       ----------------------------------------------------------
   SHARES          8.  SHARED VOTING POWER
   BENEFICIALLY        20,763,695**
   OWNED BY EACH   ----------------------------------------------------------
   PERSON WITH     9.  SOLE DISPOSITIVE POWER
                        0
                   ----------------------------------------------------------
                   10.  SHARED DISPOSITIVE POWER
                        20,763,695**
-----------------------------------------------------------------------------
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

    20,763,695**
-----------------------------------------------------------------------------
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
    CERTAIN SHARES                                                        [ ]
-----------------------------------------------------------------------------
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

    13.8%
-----------------------------------------------------------------------------
14. TYPE OF REPORTING PERSON

    00 (LLC)
-----------------------------------------------------------------------------
*See Item 3
**See Items 2 and 5





                                SCHEDULE 13D
--------------------------                          -------------------------
CUSIP NO. 896522109                                             Page 8 of 11
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This Amendment No. 6 supplements the information set forth in the Schedule
13D filed by the Reporting Persons with the United States Securities and
Exchange Commission (the "SEC"), as amended from time to time (the "Schedule
13D"), relating to Common Stock, par value $0.01 (the "Common Stock"), of
Trinity Industries, Inc., a Delaware corporation (the "Issuer"). All
capitalized terms contained herein but not otherwise defined shall have the
meanings ascribed to such terms in the Schedule 13D.

The information set forth in response to each separate Item below shall be
deemed to be a response to all Items where such information is relevant.  The
Schedule 13D is hereby supplementally amended as follows:

Item 3.    Source and Amount of Funds or Other Consideration

     The source of funds used for the purchase of the Issuer's securities
reflected in this amendment was the working capital of ValueAct Master Fund.
The aggregate funds used by these Reporting Persons to make such purchases
were $70,849,949.64.

Item 5.    Interest in Securities of the Issuer

       (a) and (b).  Set forth below is the beneficial ownership of shares of
Common Stock of the Issuer for each person named in Item 2. Shares reported
as beneficially owned by ValueAct Master Fund are also reported as
beneficially owned by (i) ValueAct Management L.P. as the manager of each
such investment partnership, (ii) ValueAct Management LLC, as General Partner
of ValueAct Management L.P., (iii) ValueAct Holdings, as the sole owner of
the limited partnership interests of ValueAct Management L.P. and the
membership interests of ValueAct Management LLC and as the majority owner of
the membership interests of VA Partners I and (iv) ValueAct Holdings GP, as
General Partner of ValueAct Holdings. Shares reported as beneficially owned
by ValueAct Master Fund are also reported as beneficially owned by VA
Partners I, as General Partner of ValueAct Master Fund. VA Partners I,
ValueAct Management L.P., ValueAct Management LLC, ValueAct Holdings and
ValueAct Holdings GP also, directly or indirectly, may own interests in one
or more than one of the partnerships from time to time. Unless otherwise
indicated below, by reason of such relationship ValueAct Master Fund is
reported as having shared power to vote or to direct the vote, and shared
power to dispose or direct the disposition of, such shares of Common Stock,
with VA Partners I (only with respect to ValueAct Master Fund), ValueAct
Management L.P., ValueAct Management LLC, ValueAct Holdings and ValueAct
Holdings GP.

         As of the date hereof, Reporting Persons beneficially own 20,763,695
shares of Common Stock, representing approximately 13.8% of the Issuer's
outstanding Common Stock. All percentages set forth in this Schedule 13D are
based upon the Issuer's reported 150,822,635 outstanding shares of Common
Stock as of January 31, 2017, as reported on the Issuer's Quarterly Report on
Form 10-K for the fiscal year ended December 31, 2017.

       (c) The following table sets forth all transactions with respect to
shares of Common Stock effected in the previous sixty days to this Schedule
13D by the Reporting Persons or on behalf of the Reporting Persons, inclusive
of any transaction effected through 4:00pm, New York City time, on March 19,
2018. The Reporting Persons undertake to provide upon request by the staff

                                SCHEDULE 13D
--------------------------                          -------------------------
CUSIP NO. 896522109                                             Page 9 of 11
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of the Securities and Exchange Commission full information regarding the
number of shares purchased in the below noted transactions at each separate
price. Except as otherwise noted below, all such transactions were purchases
or sales of shares of Common Stock effected in the open market.

                                                   Shares
Reporting Person          Trade Date    Buy/Sell   Bought/Sold    Price/Share
----------------          ----------    --------    ---------     -----------
ValueAct Master Fund      02/28/2018    Buy        350,000         $32.85
                          03/01/2018    Buy        300,000         $32.82 (1)
                          03/02/2018    Buy        300,000         $32.81 (2)
                          03/06/2018    Buy         20,539         $33.00
                          03/07/2018    Buy        168,525         $32.98 (3)
                          03/08/2018    Buy        117,279         $32.99
                          03/15/2018    Buy        300,000         $32.86 (4)
                          03/16/2018    Buy        300,000         $32.94 (5)
                          03/19/2018    Buy        300,000         $32.49 (6)

(1)   Weighted-average price at which shares were purchased (sold) on the
listed date between the range of $31.10 and $31.55 per share.
(2)   Weighted-average price at which shares were purchased (sold) on the
listed date between the range of $32.79 and $32.86 per share.
(3)   Weighted-average price at which shares were purchased (sold) on the
listed date between the range of $32.98 and $33.00 per share.
(4)   Weighted-average price at which shares were purchased (sold) on the
listed date between the range of $32.79 and $32.94 per share.
(5)   Weighted-average price at which shares were purchased (sold) on the
listed date between the range of $32.92 and $32.99 per share.
(6)   Weighted-average price at which shares were purchased (sold) on the
listed date between the range of $32.33 and $32.67 per share.

       (d) and (e)  Not applicable.

Item 6.     Contracts, Arrangements, Understandings or Relationships with
              Respect to Securities of the Issuer

       On July 28, 2016 the Reporting Persons entered into a Joint Filing
Agreement in which the parties agreed to the joint filing on behalf of each
of them of statements on Schedule 13D with respect to the securities of the
Issuer to the extent required by applicable law. The Joint Filing Agreement
is attached as an exhibit to the initial Schedule 13D and is incorporated
herein by reference.

       Other than as described in this Report and as previously reported, the
Reporting Persons have no understandings, arrangements, relationships or
contracts relating to the Issuer's Common Stock which are required to be
described hereunder.

                                 SIGNATURE
          After reasonable inquiry and to the best of his knowledge and
belief, the undersigned certifies that the information set forth in this
statement is true, complete and correct.




                                SCHEDULE 13D
--------------------------                          -------------------------
CUSIP NO. 896522109                                             Page 10 of 11
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                           POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears
below on this Schedule 13D hereby constitutes and appoints Jeffrey W. Ubben,
Bradley E. Singer, G. Mason Morfit and Allison Bennington, and each of
them, with full power to act without the other, his or its true and lawful
attorney-in-fact and agent, with full power of substitution and
resubstitution, for him or it and in his or its name, place and stead, in any
and all capacities (until revoked in writing) to sign any and all amendments
to this Schedule 13D, and to file the same, with all exhibits thereto and
other documents in connection therewith, with the Securities and Exchange
Commission, granting unto said attorneys-in-fact and agents, and each of
them, full power and authority to do and perform each and every act and thing
requisite and necessary fully to all intents and purposes as he or it might
or could do in person, thereby ratifying and confirming all that said
attorneys-in-fact and agents or any of them, or their or his substitute or
substitutes, may lawfully do or cause to be done by virtue hereof.

                              ValueAct Capital Master Fund L.P., by
                              VA Partners I, LLC, its General Partner

                              By:     /s/  Bradley E. Singer
                                --------------------------------------
Dated:  March 19, 2018       Bradley E. Singer, Chief Operating Officer


                              VA Partners I, LLC

                              By:    /s/  Bradley E. Singer
                                --------------------------------------
Dated:  March 19, 2018       Bradley E. Singer, Chief Operating Officer

                              ValueAct Capital Management, L.P., by
                              ValueAct Capital Management, LLC its
                              General Partner


                              By:    /s/  Bradley E. Singer
                                --------------------------------------
Dated:  March 19, 2018       Bradley E. Singer, Chief Operating Officer


                              ValueAct Capital Management, LLC

                              By:    /s/  Bradley E. Singer
                                --------------------------------------
Dated:  March 19, 2018       Bradley E. Singer, Chief Operating Officer


                              ValueAct Holdings, L.P., by
                              ValueAct Holdings GP, LLC, its General Partner

                              By:    /s/  Bradley E. Singer
                                --------------------------------------
Dated:  March 19, 2018       Bradley E. Singer, Chief Operating Officer

                                SCHEDULE 13D
--------------------------                          -------------------------
CUSIP NO. 896522109                                             Page 11 of 11
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      ValueAct Holdings GP, LLC

                              By:    /s/  Bradley E. Singer
                                --------------------------------------
Dated:  March 19, 2018       Bradley E. Singer, Chief Operating Officer