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                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                            ------------------------
 
                                  FORM 10-K/A
                                AMENDMENT NO. 1
 
/X/ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT
                             OF 1934 [FEE REQUIRED]
 
                  For the fiscal year ended December 28, 1996
                                       OR
 
/ / TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE
                         ACT OF 1934 [NO FEE REQUIRED]
 
                 For the transition period from       to
 
                         Commission File Number 0-22256
                            ------------------------
 
                            MONACO COACH CORPORATION
             (Exact name of Registrant as specified in its charter)
 
<TABLE>
<S>                                            <C>
                  DELAWARE                                      35-1880244
(State or other jurisdiction of incorporation      (I.R.S. Employer Identification No.)
                     or
                organization)
</TABLE>
 
                              91320 INDUSTRIAL WAY
                              COBURG, OREGON 97408
                    (Address of principal executive offices)
 
       Registrant's telephone number, including area code: (541) 686-8011
                            ------------------------
 
          Securities registered pursuant to Section 12(g) of the Act:
                     Common Stock, par value $.01 per share
                            ------------------------
 
    Indicate by check mark whether the Registrant (1) has 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 as the
Registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past ninety 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 Registrant's 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. / /
 
    The aggregate market value of the voting stock held by non-affiliates of the
Registrant, based upon the closing sale price of the Common Stock on January 5,
1998 as reported on the Nasdaq National Market, was approximately $96,232,901.
Shares of Common Stock held by officers and directors and their affiliated
entities have been excluded in that such persons may be deemed to be affiliates.
This determination of affiliate status is not necessarily conclusive for other
purposes.
 
    As of January 5, 1998, the Registrant had 5,496,499 shares of Common Stock
outstanding.
                            ------------------------
 
                      DOCUMENTS INCORPORATED BY REFERENCE
 
    None.
 
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This document consists of 10 pages. The Exhibit Index appears at page 9.
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                                     INDEX
 
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                                                                                                                PAGE
                                                                                                                -----
 
<S>                <C>                                                                                       <C>
                                                        PART III
 
ITEM 11.           EXECUTIVE COMPENSATION..................................................................           3
 
                                                        PART IV
 
ITEM 14.           EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K.........................           4
SIGNATURES         ........................................................................................           8
</TABLE>
 
                                       2
<PAGE>
ITEM 11. EXECUTIVE COMPENSATION
 
    The following table sets forth all compensation earned for services rendered
to (i) the Company during the fiscal year ended December 28, 1996, (ii) the
Company during the fiscal year ended December 30, 1995, and (iii) the Company
and the Company's predecessor during the fiscal year ended December 31, 1994 by
the Chief Executive Officer and the four other most highly compensated executive
officers of the Company (the "Named Officers"):
 
                           SUMMARY COMPENSATION TABLE
 
<TABLE>
<CAPTION>
                                                                                                SECURITIES
                                                                                                UNDERLYING
                                                                                               OPTIONS (#)
                                                                                               ------------
                                                                      ANNUAL COMPENSATION       LONG-TERM
                                                                      --------------------     COMPENSATION
NAME AND PRINCIPAL POSITION                                   YEAR     SALARY      BONUS          AWARDS
------------------------------------------------------------  ----    --------    --------     ------------
<S>                                                           <C>     <C>         <C>          <C>
Kay L. Toolson .............................................  1996    $150,000    $748,000        5,000
  Chief Executive Officer and President                       1995     150,000     352,101        5,000
                                                              1994     150,000     562,625        5,000
 
John W. Nepute .............................................  1996      65,850     145,000        2,500
  Vice President of Finance and                               1995      59,800      78,000        2,500
  Chief Financial Officer                                     1994      55,088     125,750        2,500
 
D. Page Robertson ..........................................  1996     120,000     132,500        3,000
  President of Monaco Division                                1995      81,230     171,069(1)     2,500
                                                              1994      80,000     234,750(1)     2,500
 
James V. Sheldon(2) ........................................  1996      80,769     196,000        2,500
  President of Holiday Rambler and
  Chief Operating Officer, Indiana Operations
 
B. Ray Mehaffey ............................................  1996      89,500      65,500        2,500
  Vice President of Operations                                1995      84,816      73,000        2,500
                                                              1994      83,092     119,300        2,500
</TABLE>
 
------------------------
 
(1) Includes sales commissions earned by Mr. Robertson in the amounts of $92,069
    in fiscal 1995 and $106,000 in fiscal 1994.
 
(2) Mr. Sheldon joined the Company in March 1996.
 
OPTION GRANTS
 
    The following table sets forth certain information with respect to stock
option grants during the fiscal year ended December 28, 1996. In accordance with
the rules of the Securities and Exchange Commission (the "SEC"), also shown
below is the potential realizable value over the term of the option (the period
from the grant date to the expiration date) based on assumed rates of stock
appreciation from the option exercise price of 5% and 10%, compounded annually.
These amounts are based on certain assumed rates of appreciation and do not
represent the Company's estimate of future stock price. Actual gains, if any, on
stock option exercises will be dependent on the future performance of the Common
Stock.
 
                                       3
<PAGE>
                       OPTION GRANTS IN LAST FISCAL YEAR
 
<TABLE>
<CAPTION>
                                                                                                   POTENTIAL REALIZABLE
                                                            INDIVIDUAL GRANTS (1)                    VALUE AT ASSUMED
                                             ----------------------------------------------------    ANNUAL RATES OF
                                               NUMBER OF     % OF TOTAL                                STOCK PRICE
                                              SECURITIES       OPTIONS                                 APPRECIATION
                                              UNDERLYING     GRANTED TO                              FOR OPTION TERM
                                                OPTIONS       EMPLOYEES    EXERCISE   EXPIRATION   --------------------
                   NAME                       GRANTED (#)      IN 1996       PRICE       DATE         5%         10%
-------------------------------------------  -------------  -------------  ---------  -----------  ---------  ---------
<S>                                          <C>            <C>            <C>        <C>          <C>        <C>
Kay L. Toolson.............................        5,000           9.62%   $  15.260     4/01/01   $  12,217  $  35,404
John W. Nepute.............................        2,500           4.81       13.875     4/01/06      21,815     55,283
D. Page Robertson..........................        3,000           5.77       13.875     4/01/06      26,178     66,340
James V. Sheldon...........................        2,500           4.81       13.875     4/01/06      21,815     55,283
B. Ray Mehaffey............................        2,500           4.81       13.875     4/01/06      21,815     55,283
</TABLE>
 
------------------------
 
(1) These options were granted pursuant to the Company's 1993 Incentive Stock
    Option Plan. These options vest over five years at the rate of 20% of the
    shares subject to the options at the end of each anniversary following the
    date of grant of such options.
 
OPTION VALUES
 
    The following table sets forth information with respect to the value of
unexercised options held by each of the Named Officers at December 28, 1996:
 
                         FISCAL YEAR-END OPTION VALUES
 
<TABLE>
<CAPTION>
                                                                NUMBER OF SECURITIES
                                                               UNDERLYING UNEXERCISED        VALUE OF UNEXERCISED
                                                                     OPTIONS AT            IN-THE-MONEY OPTIONS AT
                                                                  FISCAL YEAR END            FISCAL YEAR END (1)
                                                            ----------------------------  --------------------------
<S>                                                         <C>            <C>            <C>          <C>
                           NAME                              EXERCISABLE   UNEXERCISABLE  EXERCISABLE  UNEXERCISABLE
----------------------------------------------------------  -------------  -------------  -----------  -------------
Kay L. Toolson............................................        3,000         12,000           460         4,365
John W. Nepute............................................        8,340         10,560        88,186        65,487
D. Page Robertson.........................................        8,340         11,060        88,186        66,549
James V. Sheldon..........................................           --          2,500            --         5,313
B. Ray Mehaffey...........................................        8,340         10,560        88,186        65,487
</TABLE>
 
------------------------
 
(1) Value of unexercised options is based on the last reported sale price of the
    Company's Common Stock on the Nasdaq National Market of $16.00 per share on
    December 27, 1996 (the last trading day for the fiscal year ended December
    28, 1996) minus the exercise price.
 
COMPENSATION COMMITTEE INTERLOCKS AND INSIDER PARTICIPATION
 
    The Compensation Committee of the Board of Directors was established in July
1993 and consists of Directors Ring, Rouse and Vandenberg. Director Vandenberg
is affiliated with Cariad Capital, Inc., which is a party to a Management
Agreement with the Company that will terminate on September 30, 1998. Pursuant
to this agreement, Cariad received management fees of $72,000 in fiscal 1996. No
executive officer of the Company served on the compensation committee of another
entity or on any other committee of the board of directors of another entity
performing similar functions during the last fiscal year.
 
                                       4
<PAGE>
                                    PART IV
 
ITEM 14. EXHIBITS, FINANCIAL STATEMENT SCHEDULES, AND REPORTS ON FORM 8-K
 
    (a) The following documents are filed as part of this Report on Form 10-K:
 
        1.  FINANCIAL STATEMENTS.  The Consolidated Financial Statements of
    Monaco Coach Corporation and its subsidiaries and the Report of Independent
    Accountants were filed in Item 8 within the Company's Annual Report on Form
    10-K dated March 19, 1997.
 
        2.  FINANCIAL STATEMENT SCHEDULES.  The following financial statement
    schedule of Monaco Coach Corporation for the fiscal year ended December 31,
    1994, December 30, 1995 and December 28, 1996 was filed as part of the
    Company's Annual Report on Form 10-K dated March 19, 1997 and should be read
    in conjunction with the Consolidated Financial Statements, and related Notes
    thereto, of Monaco Coach Corporation.
 
<TABLE>
<CAPTION>
  SCHEDULE
-------------
<S>            <C>                                                              <C>
         II                   Valuation and Qualifying Accounts
</TABLE>
 
        Schedules not listed above have been omitted because they are not
    applicable or are not required or the information required to be set forth
    therein is included in the consolidated financial statements or notes
    thereto.
 
        3.  EXHIBITS.  The following Exhibits are filed as part of, or
    incorporated by reference into, this Report on Form 10-K.
 
<TABLE>
<S>        <C>
 2.1*      Asset Purchase Agreement dated February 4, 1993 between the Registrant,
           Warrick Industries, Inc., William L. Warrick, Arlen J. Paul, Kay L. Toolson,
           Jay M. DeVoss and James A. Krider.
 
 2.2*      First Amendment to Asset Purchase Agreement dated March 5, 1993 between
           Registrant, Warrick Industries, Inc., William L. Warrick, Arlen J. Paul, Kay
           L. Toolson, Jay M. DeVoss and James A. Krider.
 
 2.3*      Assumption Agreement dated March 5, 1993 between the Registrant and Warrick
           Industries, Inc.
 
 2.4*      Letter Agreement dated August 10, 1993 between the Registrant, Warrick
           Industries, Inc., William L. Warrick, Arlen J. Paul, Jay M. DeVoss, James A.
           Krider and Kay L. Toolson.
 
 2.5*      Asset Purchase Agreement dated as of January 21, 1996 among Harley-Davidson,
           Inc., Holiday Rambler LLC, State Road Properties L.P., and Monaco Coach
           Corporation (the "HR Asset Purchase Agreement").
 
 2.6*      Amendment No. 1 to the HR Asset Purchase Agreement dated as of March 4, 1996
           among Harley-Davidson, Inc., Holiday Rambler LLC, State Road Properties L.P.,
           and Monaco Coach Corporation.
 
 2.7*      Asset Purchase Agreement dated as of March 4, 1996 among Harley-Davidson,
           Inc., Holiday Holding Corp., Holiday World, Inc., a California corporation,
           Holiday World, Inc., a Texas corporation, Holiday World, Inc., a Florida
           corporation, Holiday World, Inc., an Oregon corporation, Holiday World, Inc.,
           an Indiana corporation, Holiday World, Inc., a Washington corporation, Holiday
           World, Inc., a New Mexico corporation, Monaco Coach Corporation and MCC
           Acquisition Corporation.
 
 2.8*      Subordinated Promissory Note, dated as of March 4, 1996, issued to Holiday
           Holding Corp. by MCC Acquisition Corporation.
</TABLE>
 
                                       5
<PAGE>
<TABLE>
<S>        <C>
 3.1*      Amended and Restated Certificate of Incorporation of Registrant.
 
 3.2*      Bylaws of Registrant, as amended to date.
 
 3.3*      Certificate of Designations of Rights, Preferences and Privileges of Series A
           Convertible Preferred Stock of Monaco Coach Corporation.
 
10.1*      Stockholders Agreement dated August 10, 1993 between the Registrant, Liberty
           Investment Partners II, the State Board of Administration of Florida ("SBA"),
           Monaco Capital Partners, Tucker Anthony Holding Corporation, Kay L. Toolson,
           Page Robertson, Ed Kinney, Ray Mehaffey, Enoch Hutchcraft, Gary Smith, John
           Nepute, Miki Scheer and C.D. Smith.
 
10.2*      Form of Indemnification Agreement for directors and executive officers.
 
10.3*+     1993 Incentive Stock Option Plan and form of option agreement thereunder.
 
10.4*+     1993 Director Option Plan.
 
10.5*+     1993 Employee Stock Purchase Plan and form of subscription agreement
           thereunder.
 
10.6*      Amended and Restated Management Agreement dated August 10, 1993 between the
           Registrant and Cariad Capital, Inc.
 
10.7*      Registration Agreement dated March 5, 1993 between the Registrant, Liberty
           Investment Partners, II and SBA.
 
10.8*      Registration Agreement dated March 5, 1993 among the Registrant, Monaco
           Capital Partners, Tucker Anthony Holding Corporation and certain other
           stockholders of the Registrant.
 
10.9*      Credit Agreement dated as of March 5, 1996 among BT Commercial Corporation,
           Deutsche Financial Services Corporation, Nationsbank of Texas, N.A., LaSalle
           National Bank and Monaco Coach Corporation.
 
10.10*     Registration Rights Agreement dated as of March 4, 1996 among Holiday Rambler
           LLC and Monaco Coach Corporation.
 
10.11(1)   Agreement of Lease dated March 4, 1996, with First Amendment dated as of March
           4, 1996, pertaining to 3 State Road 19, Wakarusa, Indiana 46573.
 
10.12(1)   Agreement of Lease dated March 4, 1996, with First Amendment dated as of March
           4, 1996, pertaining to 5 State Road 19, Wakarusa, Indiana 46573.
 
10.13(1)   Agreement of Lease dated March 4, 1996, with First Amendment dated as of March
           4, 1996, pertaining to 6 State Road 19, Wakarusa, Indiana 46573.
 
10.14(1)   Agreement of Lease dated March 4, 1996, with First Amendment dated as of March
           4, 1996, pertaining to 7 State Road 19, Wakarusa, Indiana 46573.
 
10.15(1)   Agreement of Lease dated March 4, 1996 pertaining to 8 State Road 19,
           Wakarusa, Indiana 46573.
 
10.16(1)   Form of Lease dated April 1, 1997 pertaining to 5280 High Banks Road,
           Springfild, Oregon.
 
10.17(1)   Lease Agreement dated April 1, 1995 pertaining to 1330 Wade Drive, Elkhart,
           Indiana.
 
11.1*      Computation of earnings per share (see Note 11 of Notes to Consolidated
           Financial Statements included in Item 8 hereto).
</TABLE>
 
                                       6
<PAGE>
<TABLE>
<S>        <C>
21.1*      Subsidiaries of Registrant.
 
23.1*      Consent of Independent Accountants.
 
24.1*      Power of Attorney (included on the signature pages hereof).
 
27*        Financial Data Schedule
</TABLE>
 
------------------------
 
(1) Incorporated by reference to exhibits filed in response to Item 16(a),
    "Exhibits," of the Company's Registration Statement on Form S-2 (File No.
    333-23591) declared effective on June 17, 1997.
 
 *  Previously filed.
 
 +  The item listed is a compensatory plan.
 
    (b)  REPORTS ON FORM 8-K.  No reports on Form 8-K were filed by the Company
during the quarter ended December 28, 1996.
 
                                       7
<PAGE>
                                   SIGNATURES
 
    Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the Registrant has duly caused this Report on Form 10-K to
be signed on its behalf by the undersigned, thereunto duly authorized.
 
                                          MONACO COACH CORPORATION
 
                                          By: /s/ JOHN W. NEPUTE
                                          --------------------------------------
                                          John W. Nepute
                                          CHIEF FINANCIAL OFFICER
 
January 8, 1998
 
                                       8
<PAGE>
                                 EXHIBIT INDEX
 
<TABLE>
<CAPTION>
EXHIBIT NO.                                                 EXHIBIT
-----------  -----------------------------------------------------------------------------------------------------
<S>          <C>
  2.1*       Asset Purchase Agreement dated February 4, 1993 between the Registrant, Warrick Industries, Inc.,
             William L. Warrick, Arlen J. Paul, Kay L. Toolson, Jay M. DeVoss and James A. Krider.
 
  2.2*       First Amendment to Asset Purchase Agreement dated March 5, 1993 between Registrant, Warrick
             Industries, Inc., William L. Warrick, Arlen J. Paul, Kay L. Toolson, Jay M. DeVoss and James A.
             Krider.
 
  2.3*       Assumption Agreement dated March 5, 1993 between the Registrant and Warrick Industries, Inc.
 
  2.4*       Letter Agreement dated August 10, 1993 between the Registrant, Warrick Industries, Inc., William L.
             Warrick, Arlen J. Paul, Jay M. DeVoss, James A. Krider and Kay L. Toolson.
 
  2.5*       Asset Purchase Agreement dated as of January 21, 1996 among Harley-Davidson, Inc., Holiday Rambler
             LLC, State Road Properties L.P., and Monaco Coach Corporation (the "HR Asset Purchase Agreement").
 
  2.6*       Amendment No. 1 to the HR Asset Purchase Agreement dated as of March 4, 1996 among Harley-Davidson,
             Inc., Holiday Rambler LLC, State Road Properties L.P., and Monaco Coach Corporation.
 
  2.7*       Asset Purchase Agreement dated as of March 4, 1996 among Harley-Davidson, Inc., Holiday Holding
             Corp., Holiday World, Inc., a California corporation, Holiday World, Inc., a Texas corporation,
             Holiday World, Inc., a Florida corporation, Holiday World, Inc., an Oregon corporation, Holiday
             World, Inc., an Indiana corporation, Holiday World, Inc., a Washington corporation, Holiday World,
             Inc., a New Mexico corporation, Monaco Coach Corporation and MCC Acquisition Corporation.
 
  2.8*       Subordinated Promissory Note, dated as of March 4, 1996, issued to Holiday Holding Corp. by MCC
             Acquisition Corporation.
 
  3.1*       Amended and Restated Certificate of Incorporation of Registrant.
 
  3.2*       Bylaws of Registrant, as amended to date.
 
  3.3*       Certificate of Designations of Rights, Preferences and Privileges of Series A Convertible Preferred
             Stock of Monaco Coach Corporation.
 
 10.1*       Stockholders Agreement dated August 10, 1993 between the Registrant, Liberty Investment Partners II,
             the State Board of Administration of Florida ("SBA"), Monaco Capital Partners, Tucker Anthony Holding
             Corporation, Kay L. Toolson, Page Robertson, Ed Kinney, Ray Mehaffey, Enoch Hutchcraft, Gary Smith,
             John Nepute, Miki Scheer and C.D. Smith.
 
 10.2*       Form of Indemnification Agreement for directors and executive officers.
 
 10.3*+      1993 Incentive Stock Option Plan and form of option agreement thereunder.
 
 10.4*+      1993 Director Option Plan.
 
 10.5*+      1993 Employee Stock Purchase Plan and form of subscription agreement thereunder.
 
 10.6*       Amended and Restated Management Agreement dated August 10, 1993 between the Registrant and Cariad
             Capital, Inc.
 
 10.7*       Registration Agreement dated March 5, 1993 between the Registrant, Liberty Investment Partners, II
             and SBA.
 
 10.8*       Registration Agreement dated March 5, 1993 among the Registrant, Monaco Capital Partners, Tucker
             Anthony Holding Corporation and certain other stockholders of the Registrant.
</TABLE>
<PAGE>
<TABLE>
<S>          <C>
 10.9*       Credit Agreement dated as of March 5, 1996 among BT Commercial Corporation, Deutsche Financial
             Services Corporation, Nationsbank of Texas, N.A., LaSalle National Bank and Monaco Coach Corporation.
 
 10.10*      Registration Rights Agreement dated as of March 4, 1996 among Holiday Rambler LLC and Monaco Coach
             Corporation.
 
 10.11(1)    Agreement of Lease dated March 4, 1996, with First Amendment dated as of March 4, 1996, pertaining to
             3 State Road 19, Wakarusa, Indiana 46573.
 
 10.12(1)    Agreement of Lease dated March 4, 1996, with First Amendment dated as of March 4, 1996, pertaining to
             5 State Road 19, Wakarusa, Indiana 46573.
 
 10.13(1)    Agreement of Lease dated March 4, 1996, with First Amendment dated as of March 4, 1996, pertaining to
             6 State Road 19, Wakarusa, Indiana 46573.
 
 10.14(1)    Agreement of Lease dated March 4, 1996, with First Amendment dated as of March 4, 1996, pertaining to
             7 State Road 19, Wakarusa, Indiana 46573.
 
 10.15(1)    Agreement of Lease dated March 4, 1996 pertaining to 8 State Road 19, Wakarusa, Indiana 46573.
 
 10.16(1)    Form of Lease dated April 1, 1997 pertaining to 5280 High Banks Road, Springfield, Oregon.
 
 10.17(1)    Lease Agreement dated April 1, 1995 pertaining to 1330 Wade Drive, Elkhart, Indiana.
 
 11.1*       Computation of earnings per share (see Note 11 of Notes to Consolidated Financial Statements included
             in Item 8 hereto).
 
 21.1*       Subsidiaries of Registrant.
 
 23.1*       Consent of Independent Accountants.
 
 24.1*       Power of Attorney (included on the signature pages hereof).
 
 27*         Financial Data Schedule
</TABLE>
 
------------------------
 
(1) Incorporated by reference to exhibits filed in response to Item 16(a),
    "Exhibits," of the Company's Registration Statement on Form S-2 (File No.
    333-23591) declared effective on June 17, 1997.
 
 *  Previously filed.
 
 +  The item listed is a compensatory plan.