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                       SECURITIES AND EXCHANGE COMMISSION
 
                             WASHINGTON, D.C. 20549
                            ------------------------
 
                                  FORM 10-K/A
 
             JOINT ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF
 
             THE SECURITIES AND EXCHANGE ACT OF 1934 (FEE REQUIRED)
 
                   FOR THE FISCAL YEAR ENDED OCTOBER 31, 1998
                            ------------------------
 
<TABLE>
<S>                                              <C>
      COMMISSION FILE NUMBER 33-49544-01                 COMMISSION FILE NUMBER 33-49544
             BLUE BIRD CORPORATION                           BLUE BIRD BODY COMPANY
       ---------------------------------                ---------------------------------
         (Exact name of registrant as                     (Exact name of registrant as
           specified in its charter)                        specified in its charter)
 
                   DELAWARE                                          GEORGIA
       ---------------------------------                ---------------------------------
         (State or other jurisdiction                     (State or other jurisdiction
       of incorporation or organization)                of incorporation or organization)
 
                  13-3638126                                       58-0813156
       ---------------------------------                ---------------------------------
     (I.R.S. Employer Identification No.)             (I.R.S. Employer Identification No.)
 
              3920 ARKWRIGHT ROAD                              3920 ARKWRIGHT ROAD
             MACON, GEORGIA 31210                             MACON, GEORGIA 31210
       ---------------------------------                ---------------------------------
        (Address of principal executive                  (Address of principal executive
          offices including ZIP code)                      offices including ZIP code)
 
                (912) 757-7100                                   (912) 757-7100
       ---------------------------------                ---------------------------------
        (Registrant's telephone number,                  (Registrant's telephone number,
             including area code)                             including area code)
 
                  SECURITIES REGISTERED PURSUANT TO SECTION 12(b) OF THE ACT:
 
                     NONE                                             NONE
       ---------------------------------                ---------------------------------
               (Title of class)                                 (Title of class)
 
                  SECURITIES REGISTERED PURSUANT TO SECTION 12(g) OF THE ACT:
                     NONE                                             NONE
       ---------------------------------                ---------------------------------
               (Title of class)                                 (Title of class)
</TABLE>
 
                            ------------------------
 
    Indicate by check mark whether the registrants (1) have filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrants were required to file such reports), and (2) have been subject to
such filing requirements for the past 90 days. Yes /X/    No / /
 
    Indicate by check mark if disclosure of delinquent filers pursuant to Item
405 of Regulation S-K is not contained herein, and will not be contained, to the
best of registrants' knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. /X/
 
    All of the voting stock of the registrants is held by affiliates. All
officers, directors and more than 5% stockholders of the registrants are deemed
"affiliates" of the registrants for the purpose of determining the foregoing.
The registrants, however, do not represent that such persons, or any of them,
would be deemed "affiliates" of the registrants for any other purpose under the
Securities Exchange Act of 1934 or the Securities Act of 1933.
 
    As of January 1, 1999, 9,204,778 shares of Blue Bird Corporation's common
stock and 10 shares of Blue Bird Body Company's common stock were outstanding.
 
    BLUE BIRD BODY COMPANY IS A WHOLLY-OWNED SUBSIDIARY OF BLUE BIRD
CORPORATION. BLUE BIRD BODY COMPANY MEETS THE CONDITIONS SET FORTH IN GENERAL
INSTRUCTION I(1)(a) AND (b) OF FORM 10-K AND IS THEREFORE FILING CERTAIN
PORTIONS OF THIS FORM 10-K APPLICABLE TO IT WITH THE REDUCED DISCLOSURE FORMAT.
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    EXPLANATORY NOTE: Due to transmission errors, the signature pages to the
Joint Annual Report on Form 10-K of Blue Bird Corporation and Blue Bird Body
Company for the fiscal year ended October 31, 1998 (the "Report"), filed with
the Securities and Exchange Commission (the "Commission") on January 29, 1999,
did not clearly indicate the signatories thereto. In accordance with Rule 302(b)
of Regulation S-T, the signature pages to the Report were manually executed by
each of the signatories thereto at the time the Report was filed with the
Commission and such manually signed signature pages shall be retained by the
filers in accordance with such rule. This amendment is being filed to more
clearly evidence the signatories to the Report.
<PAGE>
                                   SIGNATURES
 
    Pursuant to the requirements of the Section 13 or 15(d) of the Securities
Exchange Act of 1934, each Registrant has duly caused this report to be signed
on its behalf by the undersigned, thereunto duly authorized.
 
                                BLUE BIRD CORPORATION
 
                                BY               /S/ PAUL E. GLASKE
                                     ------------------------------------------
                                                   Paul E. Glaske
                                      CHAIRMAN OF THE BOARD AND PRESIDENT AND
                                                      DIRECTOR
                                           (PRINCIPAL EXECUTIVE OFFICER)
 
                                Date: January 29, 1999
 
                                BLUE BIRD BODY COMPANY
 
                                BY               /S/ PAUL E. GLASKE
                                     ------------------------------------------
                                                   Paul E. Glaske
                                      CHAIRMAN OF THE BOARD AND PRESIDENT AND
                                                      DIRECTOR
                                           (PRINCIPAL EXECUTIVE OFFICER)
 
                                Date: January 29, 1999
 
    Pursuant to the requirements of the Securities Exchange Act of 1934, this
registration statement or amendment thereto has been signed below by the
following persons in the capacities and on January 29, 1999.
 
                             BLUE BIRD CORPORATION
 
<TABLE>
<CAPTION>
          SIGNATURE                       TITLE                    DATE
------------------------------  --------------------------  -------------------
<C>                             <S>                         <C>
 
                                Chairman of the Board and
      /s/ PAUL E. GLASKE          President and Director
------------------------------    (Principal Executive       January 29, 1999
        Paul E. Glaske            Officer)
 
                                Vice President, Treasurer
     /s/ BOBBY G. WALLACE         and Secretary and
------------------------------    Director (Principal        January 29, 1999
       Bobby G. Wallace           Financial and Accounting
                                  Officer)
 
   /s/ GERALD S. ARMSTRONG
------------------------------  Director                     January 29, 1999
     Gerald S. Armstrong
 
     /s/ ALEXIS P. MICHAS
------------------------------  Director                     January 29, 1999
       Alexis P. Michas
 
    /s/ DONALD C. TRAUSCHT
------------------------------  Director                     January 29, 1999
      Donald C. Trauscht
 
    /s/ A. CLARK DAUGHERTY
------------------------------  Director                     January 29, 1999
      A. Clark Daugherty
</TABLE>
 
                                       33
<PAGE>
                             BLUE BIRD BODY COMPANY
 
<TABLE>
<CAPTION>
          SIGNATURE                       TITLE                    DATE
------------------------------  --------------------------  -------------------
<C>                             <S>                         <C>
 
                                Chairman of the Board and
      /s/ PAUL E. GLASKE          President and Director
------------------------------    (Principal Executive       January 29, 1999
        Paul E. Glaske            Officer)
 
                                Vice President, Treasurer
     /s/ BOBBY G. WALLACE         and Secretary and
------------------------------    Director (Principal        January 29, 1999
       Bobby G. Wallace           Financial and Accounting
                                  Officer)
 
   /s/ GERALD S. ARMSTRONG
------------------------------  Director                     January 29, 1999
     Gerald S. Armstrong
 
     /s/ ALEXIS P. MICHAS
------------------------------  Director                     January 29, 1999
       Alexis P. Michas
 
    /s/ DONALD C. TRAUSCHT
------------------------------  Director                     January 29, 1999
      Donald C. Trauscht
 
    /s/ A. CLARK DAUGHERTY
------------------------------  Director                     January 29, 1999
      A. Clark Daugherty
</TABLE>
 
                                       34
<PAGE>
                                   SIGNATURES
 
    Pursuant to the requirements of the Securities Exchange Act of 1934, each
Registrant has duly caused this report to be signed on its behalf by the
undersigned, thereunto duly authorized.
 
<TABLE>
<S> <C>                                                            <C> <C>
BLUE BIRD CORPORATION                                              BLUE BIRD BODY COMPANY
 
By:                      /S/ PAUL E. GLASKE                        By:                      /S/ PAUL E. GLASKE
               ---------------------------------------                            ---------------------------------------
                           Paul E. Glaske                                                     Paul E. Glaske
 
                           Paul E. Glaske                                                     Paul E. Glaske
                      Chairman of the Board and                                          Chairman of the Board and
                       President and Director                                             President and Director
                    (Principal Executive Officer)                                      (Principal Executive Officer)
 
Date: February 4, 1999                                             Date: February 4, 1999
 
By:                     /S/ BOBBY G. WALLACE                       By:                     /S/ BOBBY G. WALLACE
               ---------------------------------------                            ---------------------------------------
                          Bobby G. Wallace                                                   Bobby G. Wallace
 
                          Bobby G. Wallace                                                   Bobby G. Wallace
                    Vice President, Treasurer and                                         Vice President--Finance
                       Secretary and Director                                               and Administration,
                      (Principal Financial and                                            Treasurer and Secretary
                         Accounting Officer)                                                   and Director
                                                                                         (Principal Financial and
                                                                                            Accounting Officer)
 
Date: February 4, 1999                                             Date: February 4, 1999
</TABLE>
 
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