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                                                                    EXHIBIT 4.1




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                             GREYHOUND LINES, INC.

                                      and

                          THE GUARANTORS NAMED HEREIN


                    ----------------------------------------


                             SERIES A AND SERIES B

                         11 1/2% SENIOR NOTES DUE 2007

                    ----------------------------------------


                               -------------------

                          SECOND SUPPLEMENTAL INDENTURE


                           DATED AS OF AUGUST 25, 1997

                               -------------------


                         PNC BANK, NATIONAL ASSOCIATION

                                     Trustee




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         This SECOND SUPPLEMENTAL INDENTURE, dated as of August [25], 1997,
among Greyhound Lines, Inc., a Delaware corporation (the "Company"), each of the
parties identified under the caption "Guarantors" on the signature pages hereto
(the "Guarantors") and PNC Bank, National Association, as Trustee.

                                    RECITALS

         WHEREAS, the Company and the Trustee entered into an Indenture, dated
as of April 16, 1997 (the "Indenture"), pursuant to which the Company issued
$150,000,000 in principal amount of 11 1/2% Senior Notes due 2007 (the "Notes");
and

         WHEREAS, Section 9.01(e) of the Indenture provides that the Company and
the Trustee may amend or supplement the Indenture in order to execute a
guarantee (a "Subsidiary Guarantee") to comply with Section 10.02 thereof
without the consent of the Holders of the Notes; and

         WHEREAS, all acts and things prescribed by the Indenture, by law and by
the Certificate of Incorporation and the Bylaws of the Company, of the
Guarantors and of the Trustee necessary to make this Second Supplemental
Indenture a valid instrument legally binding on the Company, the Guarantors and
the Trustee, in accordance with its terms, have been duly done and performed;

         NOW, THEREFORE, to comply with the provisions of the Indenture and in
consideration of the above premises, the Company, the Guarantors and the Trustee
covenant and agree for the equal and proportionate benefit of the respective
Holders of the Notes as follows:

                                    ARTICLE 1

         SECTION 1.01. This Second Supplemental Indenture is supplemental to the
Indenture and does and shall be deemed to form a part of, and shall be construed
in connection with and as part of, the Indenture for any and all purposes.

         SECTION 1.02. This Second Supplemental Indenture shall become effective
immediately upon its execution and delivery by each of the Company, the
Guarantors and the Trustee.



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                                    ARTICLE 2

         From this date, in accordance with Section 10.02 and by executing this
Second Supplemental Indenture and the accompanying Subsidiary Guarantee (a copy
of which is attached hereto), the Guarantors whose signatures appear below are
subject to the provisions of the Indenture to the extent provided for in Article
10 thereunder.

                                    ARTICLE 3

         SECTION 3.01. Except as specifically modified herein, the Indenture and
the Notes are in all respects ratified and confirmed (mutatis mutandis) and
shall remain in full force and effect in accordance with their terms with all
capitalized terms used herein without definition having the same respective
meanings ascribed to them as in the Indenture.

         SECTION 3.02. Except as otherwise expressly provided herein, no duties,
responsibilities or liabilities are assumed, or shall be construed to be
assumed, by the Trustee by reason of this Second Supplemental Indenture. This
Second Supplemental Indenture is executed and accepted by the Trustee subject to
all the terms and conditions set forth in the Indenture with the same force and
effect as if those terms and conditions were repeated at length herein and made
applicable to the Trustee with respect hereto.

         SECTION 3.03. THE INTERNAL LAW OF THE STATE OF NEW YORK SHALL GOVERN
AND BE USED TO CONSTRUE THIS SECOND Supplemental INDENTURE, THE NOTES AND THE
SUBSIDIARY GUARANTEES.

         SECTION 3.04. The parties may sign any number of copies of this Second
Supplemental Indenture. Each signed copy shall be an original, but all of such
executed copies together shall represent the same agreement.

                          [NEXT PAGE IS SIGNATURE PAGE]




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         IN WITNESS WHEREOF, the parties hereto have caused this Second
Supplemental Indenture to be duly executed, all as of the date first written
above.


                                     GREYHOUND LINES, INC.



                                     By:  /s/ Steven L. Korby
                                        ---------------------------------------
                                        Steven L. Korby, Executive Vice
                                         President and Chief Financial
                                          Officer


                                     GUARANTORS:

                                     VALLEY TRANSIT CO., INC.



                                     By:  /s/ Steven L. Korby
                                        ---------------------------------------
                                        Steven L. Korby, Executive Vice
                                         President and Chief Financial
                                          Officer



                                     VALLEY BUS CO., INC.



                                     By:  /s/ Steven L. Korby
                                        ---------------------------------------
                                        Steven L. Korby, Executive Vice
                                         President and Chief Financial
                                          Officer




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<PAGE>   5



                                     VALLEY EXPRESS COMPANY


                                     By:  /s/  Steven L. Korby
                                        ---------------------------------------
                                        Steven L. Korby, Executive Vice
                                         President and Chief Financial
                                          Officer


                                     VALLEY GMC TRUCK CO.



                                     By:  /s/  Steven L. Korby
                                        ---------------------------------------
                                        Steven L. Korby, Executive Vice
                                         President and Chief Financial
                                          Officer


                                     VALLEY BUS SERVICE COMPANY



                                     By:  /s/  Steven L. Korby
                                        ---------------------------------------
                                        Steven L. Korby, Executive Vice
                                         President and Chief Financial
                                          Officer


                                     VALLEY GARAGE COMPANY, INC.


                                     By:  /s/  Steven L. Korby
                                        ---------------------------------------
                                        Steven L. Korby, Executive Vice
                                         President and Chief Financial
                                          Officer




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                                     V.D.R. SERVICES, INC.


                                     By:  /s/  Steven L. Korby
                                        ---------------------------------------
                                        Steven L. Korby, Executive Vice
                                         President and Chief Financial
                                          Officer


                                     FIRST BUS CORP.


                                     By:  /s/  Steven L. Korby
                                        ---------------------------------------
                                        Steven L. Korby, Executive Vice
                                         President and Chief Financial
                                          Officer


                                     MOTOR COACH LEASING COMPANY, INC.


                                     By:  /s/  Steven L. Korby
                                        ---------------------------------------
                                        Steven L. Korby, Executive Vice
                                         President and Chief Financial
                                          Officer


                                     FIRST TEXAS COMMERCIAL, INC.


                                     By:  /s/  Steven L. Korby
                                        ---------------------------------------
                                        Steven L. Korby, Executive Vice
                                         President and Chief Financial
                                          Officer





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                                     PNC BANK, NATIONAL ASSOCIATION,
                                       as trustee

                                     By:
                                        ---------------------------------------
                                        Name:
                                        Title:





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