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                                                                    EXHIBIT 10.4

                               THIRD AMENDMENT TO
                     SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN

         This Third Amendment to the Greyhound Lines, Inc. (the "Company")
Supplemental Executive Retirement Plan is made effective as of August 1, 2003.

         WHEREAS, the Company previously adopted the Greyhound Lines, Inc.
Supplemental Executive Retirement Plan, as restated effective January 1, 1994,
and as amended by the First Amendment dated as of December 9, 1996 and as
further amended by the Second Amendment dated as of January 20, 1999 (the
"Plan"); and

         WHEREAS, the Company, having sought the approval of the Board of
Directors of the Company, desires to amend the Plan as set forth herein.

         NOW THEREFORE, the Plan shall be amended as follows:

1.       Section 2.1(b) of the Plan shall be amended by deleting the first
sentence thereof and by replacing it with the following:

                  "'Annual Base Salary' shall mean a Participant's base salary
                  actually earned by a Participant for services performed for
                  the Sponsor for a calendar year and, to the extent
                  specifically designated by the Committee, for services
                  performed for an affiliate or a subsidiary of the Sponsor for
                  a calendar year."

2.       Section 5.1 of the Plan shall be amended by adding the following to the
end thereof:

                  "Notwithstanding the foregoing, if a Participant terminates
                  his employment with the Sponsor or an affiliate or subsidiary
                  and immediately thereafter commences new employment with an
                  affiliate or subsidiary of the Sponsor for which the
                  Participant's earnings are not considered Annual Base Salary
                  hereunder, then the Participant shall be entitled to the
                  payment of a benefit equal to the vested portion of his
                  Account balance as of the later of (i) the date of his
                  termination of employment with the Sponsor or its affiliate or
                  its subsidiary for which the Participant's earnings were
                  considered Annual Base Salary, or (ii) the date on which the
                  Participant will have 5 or more Years of

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                  Service or would otherwise be fully-vested in his Account
                  under Article IV. In such event:

                  (a)      the Participant's Account balance to be paid shall
                           include (i) immediate benefit credits for any partial
                           Plan Year ending as of the date the Participant
                           terminates employment, notwithstanding the
                           provisions of Section 6.1 of the Plan; and (ii)
                           investment earnings accruing through the date of
                           payment entitlement hereunder, notwithstanding the
                           provisions of Section 6.3 of the Plan; and

                  (b)      notwithstanding the provisions of Section 5.2 of the
                           Plan, the value of a Participant's Account shall be
                           determined as of the date of payment entitlement
                           hereunder, after the application of the provisions
                           set forth in (a) above.

3.       Capitalized terms used herein without definition shall have the meaning
ascribed to such terms as set forth in the Plan.

                                                    GREYHOUND LINES, INC.

                                                    By: ________________________
                                                             Stephen E. Gorman
                                                             President and CEO

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