<PAGE>   1
                                 United States
                       Securities and Exchange Commission
                              Washington D.C. 20549

                                   FORM 10-K

(Mark One)
[ X ]    ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES 
         EXCHANGE ACT OF 1934

         For the fiscal year ended August 31, 1998

                                       OR

[   ]    TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES 
         EXCHANGE ACT OF 1934

                        Commission file number 001-12673

                              RIVIERA TOOL COMPANY
             (Exact name of registrant as specified in its charter)

                   MICHIGAN                         38-2828870
    ---------------------------------------    ----------------------
       (State or other jurisdiction of            (I.R.S. Employer
       incorporation or organization)            Identification No.)
                                 

          5460 EXECUTIVE PARKWAY SE
               GRAND RAPIDS, MI                        49512
    ----------------------------------------    ----------------------
    (Address of principal executive offices)         (Zip Code)
       

       Registrant's telephone number, including area code: (616) 698-2100

    Securities registered pursuant to Section 12(b) of the Act: Common Stock,
                                  no par value

            Securities registered pursuant to 12(g) of the Act: None

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 shorter period that the registrant was required
to file such reports), and (2) has 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 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. [ X ]

The aggregate market value of the voting common stock of the Registrant (based
upon the last reported sale of the Common Stock at that date by the American
Stock Exchange) held by non-affiliates was $16,363,981 as of November 17, 1998.

The number of shares  outstanding  of the  Registrant's  common  stock as of 
November  23, 1998 was  3,218,744  shares of common  stock without par value.

                      DOCUMENTS INCORPORATED BY REFERENCE:

<TABLE>
<CAPTION>

                                                                               Part of Form 10-K Into Which Portions
                          Document                                                 of Documents are Incorporated
--------------------------------------------------------------      ------------------------------------------------------------
<S>                                                                           <C>
Riviera Tool Company 1998 Annual Report to  Shareholders.                               Parts I, II and IV

Definitive Proxy Statement for the 1998 Annual Meeting of                                   Part III
Shareholders filed with the Securities and Exchange 
Commission, November, 1998.

</TABLE>

                                       1
<PAGE>   2
                             RIVIERA TOOL COMPANY

                           Annual Report on Form 10-K

                                November 23, 1998


                                TABLE OF CONTENTS
<TABLE>
<CAPTION>

                                                        PART I                                        PAGE
                                                        ------                                      

<S>                  <C>                                                                              <C>
Item 1.              Business........................................................................   3
Item 2.              Properties......................................................................   8
Item 3.              Legal Proceedings...............................................................   9
Item 4.              Submission of Matters to a Vote of Security Holders.............................   9


                                                        PART II
                                                        -------

Item 5.              Market for the Registrant's Common Stock and
                     Related Stockholder Matters.....................................................   9
Item 6.              Selected Financial Data.........................................................  10
Item 7.              Management's Discussion and Analysis of Financial
                     Condition and Results of Operations.............................................  10
Item 8.              Financial Statements and Supplemental Data......................................  10
Item 9.              Changes in and Disagreements with Accountants
                     on Accounting and Financial Disclosure..........................................  11


                                                        PART III
                                                        --------

Item 10.             Directors and Executive Officers of the Registrant..............................  11
Item 11.             Executive Compensation..........................................................  11
Item 12.             Security Ownership of Certain Beneficial Owners and Management..................  11
Item 13.             Certain Relationships and Related Transactions..................................  11


                                                        PART IV
                                                        -------

Item 14.             Exhibits, Financial Statement Schedules, and Reports on Form 8-K - Index........ 11-13


                     SIGNATURES......................................................................  14
</TABLE>

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                                     PART I

ITEM 1.      BUSINESS

    GENERAL

    The Company is a leading designer and manufacturer of large scale, complex
stamping die systems used to form sheet metal parts. Most of the stamping die
systems sold by the Company are used in the production of automobile and truck
body parts such as doors, door frames, structural components and bumpers. The
following table sets forth the Company's sales (in millions) and percentage of
total sales by customer in fiscal years 1994, 1995, 1996, 1997 and 1998.

<TABLE>
<CAPTION>

                                                                        YEAR ENDED AUGUST 31,
-------------------------------------------------------------------------------------------------------------------------------
               CUSTOMER                     1994              1995              1996            1997              1998
-------------------------------------------------------- ----------------- ---------------- --------------- ------------------
                                        AMOUNT     %      AMOUNT    %       AMOUNT    %      AMOUNT     %     AMOUNT     %
                                       ----------------- ----------------- ---------------- --------------- ------------------
<S>                                    <C>        <C>    <C>       <C>     <C>      <C>     <C>      <C>    <C>      <C>
Chrysler  Corporation..................$  6.9     31%    $  4.6     24%    $  4.6     25%   $ 8.9     40%   $  2.3    10%

Suppliers of Chrysler Corp. ...........     0      *          0      *          0      *       .7      3       1.5     7

Ford Motor Company.....................   1.9      8        1.3      7        2.1     11      3.4     16         0     *

Suppliers of Ford Motor Company........   6.9     31       10.4     55        3.0     17      3.4     16       6.0    26

General Motors Corporation.............     0      *         .2      1        2.3     13       .9      4       5.2    23

Suppliers of General Motors 
Corporation............................     0      *          0      *        1.6      9      1.8      8       6.0    27

Other auto and  truck manufacturers
And their suppliers....................   6.7     30        2.5     13        4.7     25      2.8     13       1.6     7
                                       ----------------- ----------------- ---------------- --------------- ------------------

Total Sales............................$ 22.4    100%    $ 19.0    100%    $ 18.3    100%   $21.9    100%   $ 22.6   100%
                                       ================= ================= ================ =============== ==================
</TABLE>
----------
*    Less than 1.0% of the Company's total sales.


INDUSTRY TRENDS

      The automotive industry continues to evolve towards the early stages of
convergence between the OEM's and the supplier base. This trend will result in
the OEM's focusing their capital expenditures on marketing and distribution,
rather than manufacturing. A recent Bear Sterns & Co. Inc. automotive parts
industry report (1) noted that the OEM's greatest single asset is their brands
and that independent suppliers will become a critical component of the design,
engineering and delivery of systems which will increasingly be outsourced in the
future.

      Other significant trends within the North American automotive industry
have had, and are likely to continue to have, an impact on the Company's
business. Over the past several years, the industry has required that its tool
suppliers utilize advanced computer integrated technology. This has required
significant capital investment. In some cases, being unable or unwilling to make
this investment, many independent tooling suppliers have exited the business.
This has decreased the available domestic tooling capacity and has resulted in
fewer qualified suppliers.

    The automotive industry's trend towards shorter product life cycles and
introduction of a greater number of vehicle models will create growing demand
for the Company's complex tooling systems. In accordance with this trend,
Chrysler Corporation ("Chrysler"), Ford Motor Company ("Ford") and General
Motors Corporation ("General Motors"), the three largest domestic automobile
manufacturers (the "OEMs"), are forming alliances with select suppliers which
have the technological capability to successfully perform simultaneous
engineering of product and manufacturing processes from concept to completion at
the supplier level and utilizing computer data based design, manufacturing and
validation processes. The OEMs have formed "Platform" teams which provide the
organizational 

------------------------------------
(1) Source: Bear Sterns Equity Research Report on the Auto Parts Industry, dated
    September, 1998.

                                       3
<PAGE>   4
structure for this simultaneous engineering process, and have included their
critical or key suppliers in these teams. This simultaneous engineering concept
allows model changes to be implemented more quickly and cost-effectively. By
involving the ultimate tool and die manufacturer early in the design process,
the OEMs are better able to design-in more cost-effective manufacturing
processes, improve product quality, and avoid costly changes downstream.
Chrysler and Ford are currently operating Platform teams and management believes
that General Motors will implement this concept within the near future.

     A recent report (2) on Light Car and Truck Product Cycle by Manufacturer --
U.S. Market, indicated the following trends of "major changes" and "facelifts"
by manufacturer (foreign and domestic) for vehicles in the U.S. market:

<TABLE>
<CAPTION>

                     Model                               Major
                      Year          "Facelifts"         Changes           Total
                 ----------------   -------------     -------------    -------------
                 <S>                <C>               <C>              <C>              
                 1999............        11                23               34
                 2000............        10                33               43
                 2001............        12                25               37
                 2002............         9                40               49
                                    -------------     -------------    -------------
                     Total               42               121              163
                                    =============     =============    =============
</TABLE>

    The emphasis on designing and manufacturing more fuel efficient vehicles as
the result of federal Corporate Average Fuel Economy ("C.A.F.E.") regulation has
produced many new vehicle designs. In addition, automobile manufacturers are
utilizing light-weight, high strength steels and aluminum in new model designs
in order to decrease the weight of the vehicle and increase fuel efficiency.
Therefore, suppliers will be required to have the ability to work with these
types of materials in order to remain competitive. The Company has established
an expertise in manufacturing dies used in the production of structural
components made of light-weight, high strength steels and aluminum (largely
utilized in large semi-trucks).

    Chrysler, Ford and General Motors have developed "cash accumulation
policies." These policies entail the establishing and maintaining of cash
reserves to fund new model development during industry downturns. These policies
should create increased and more stable demand for the Company's products and
services in the future should new car sales volumes were to decrease. As of June
30, 1998, Chrysler had accumulated $7.0 billion, Ford $9.0 billion and General
Motors $22 billion, for such development during future industry downturns.(3)
General Motors stated in its 1996 mid-year Report to Shareholders that this cash
accumulation "will enable us to weather the next industry down cycle without
sacrificing any of our product programs, which is critical for long-term
success". (4)

    Efforts by OEMs and their suppliers to reduce labor and other manufacturing
costs have resulted in their tending to combine common parts into a single
stamping press and reduce the number of "hits" required to manufacture a part.
In addition, utilization of transfer presses has increased demand for transfer
dies to reduce labor cost at the OEMs and their suppliers. The Company believes
that it is one of only a few North American independent suppliers that have the
capability to both design and produce large complex transfer dies.

    Management believes these industry trends will continue with emphasis on
simultaneous engineering and manufacturing processes centered around the
utilization of fully computer integrated technologies. This should increase the
Company's customer relationships with and importance to the OEMs and their tier
one suppliers of sheet metal stamped parts and assemblies.

  (2) Source: Bear Sterns Equity Research Report on the Auto Parts Industry, 
      dated September, 1998.
  (3) Source: Chrysler Corporation, Ford Motor Company and General Motors 
      Corporation Securities and Exchange
      Commission Form 10Q for the quarter ended June 30, 1998.
  (4) Source: General Motors Midyear Report to Shareholders, dated September 10,
      1996.

                                       4
<PAGE>   5
PRODUCTS AND SERVICES

    Dies. The Company's dies are used in the high speed production of sheet
metal stamped parts and assemblies. Production of such parts is a multiple step
process involving a series of dies. Typically, the first die is used to cut the
appropriate size metal blank from a sheet or coil of steel. The next die draws
the metal blank into its primary shape and subsequent dies are used to bend
edges or corners, create flanges, trim off excess metal and pierce assembly
holes. A customer usually orders only one series of dies for each separate part.
Normally, the dies do not require replacement due to usage because the life of
well maintained dies is sufficient to carry production to the point when styling
changes dictate production of new dies. The dies manufactured by the Company
generally include automation features, adding to the complexity of design and
construction. These automation features facilitate rapid introduction and
removal of the work piece or raw material into and out of the die, thereby
increasing production speeds and reducing labor cost.

    During fiscal 1998, the Company purchased four large stamping presses and is
in the process of installing such presses. These additional presses will provide
the Company the opportunity to manufacture the largest parts used in an
automobile. These parts would include double attached doors, body side apertures
and very large hood and deck panels. The Company believes it is only one of
three domestic die manufacturers and one of only eight in the world with this
capacity. Upon installation of these presses, the Company believes it will
benefit as these types of large dies can result in larger contracts. For
example, a set of stamping dies currently manufactured by the Company generally
sells for between $250,000 and $2,000,000 depending upon size and complexity,
whereas a body side aperture can sell for between $4,000,000 and $6,000,000.

     Simultaneous Engineering of Product and Process. The OEMs are developing
organizational structures involving internal design and engineering personnel as
well as supplier representatives which they are using to develop new car models.
These organizations are called "Platform" teams. This allows full implementation
of simultaneous engineering -- the application of the product engineering and
process engineering functions simultaneously and early in the process. The
Company utilizes advanced Computer Aided Design/Computer Aided Manufacturing
("CAD/CAM") technology to design and manufacture its complex stamping dies. Due
to this advanced computer capability, the Company is able to work very closely
with its customers and is often assigned to these Platform teams early. Its
process engineering input facilitates the teams' goals of introducing new models
rapidly and efficiently. The Company has invested significantly to ensure that
it remains one of the few domestic tool and die firms with advanced technology
capabilities and is one of only a few independent suppliers capable of receiving
and working directly from complex mathematical data received from its OEM
customers. Although several of its competitors also utilize CAD/CAM technology,
management believes the Company is one of only a few suppliers who have
successfully integrated mathematical data into their on-site design,
manufacturing and validation processes across their product line. Management's
investment in, and commitment to, advanced technology has solidified its quality
reputation with its customers and helped the Company advance to tier one status.

    Prototype Tooling and Parts. With the advent of Platform team and
simultaneous engineering methods, the Company has become responsible for the
design and manufacture of both the prototype tooling, the final production
tooling and specifies the final production process. Prototype tooling and parts
are utilized during the design phase of new models which the automobile
manufacturers use to validate the fit and function of the respective components
and assemblies and the repeatability of the respective production processes. The
parts manufactured from prototype tools are also often used in crash testing.

    Typically, prototype tools associated with the primary metal forming
operations are manufactured from an alloy casting or mild steel and subsequently
machined using the mathematical data base and related Computer Numerically
Controlled ("CNC") programs. After machining, the prototype tools are assembled
and tested to validate the integrity and repeatability of the final
manufacturing process. The results of the validation process are 

                                       5
<PAGE>   6

incorporated into the mathematical data base which will then be used to
manufacture the final production tools. After testing the primary forming
operations, prototype parts are manufactured using special means such as
computerized laser cutting machines to trim off excess scrap and to incorporate
various slots and holes. These parts are then sent to the automobile
manufacturers for further testing and evaluation. The results of this testing
and evaluation may require the incorporation of additional design and
manufacturing process modifications.

MANUFACTURING

    Traditionally, the die manufacturing process was comprised of various manual
steps performed by craftsmen. After being awarded a contract, the Company would
be presented with a wooden model of the part to be produced. From the model,
plaster tooling aids were constructed. The plaster tooling aids were then traced
and cut into steel. The steel was then ground, usually quite extensively, by
hand to fit. Validation was also done by hand by measuring specific points on
the die face and comparing these to the original design blueprints. Today, with
the Company's technology, the design and most of the manufacturing process is
computer-driven, which increases accuracy and reduces the time required to
produce a set of stamping dies. The process starts when the Company is assigned
to a new Platform team and simultaneous engineering begins. An electronic
"model" of the part to be produced is transmitted directly to the Company by
transferring design information electronically ("EDI"), or sent on computer disk
represented as a mathematical database. Company engineers use the mathematical
database to generate computer-aided die designs and die face cutter path
programs. These cutter path programs are used by the tool makers and machinists
to manufacture the inner workings of the tool. Most material is removed and the
cutting is done by CNC machine tools which utilize the computer-generated cutter
path programs. Depending on the complexity of the tool, a prototype may be
manufactured to prove-out the manufacturing process or to provide actual parts
for crash testing and to test fit and function. Finally, after the die is
constructed, it is evaluated statistically for process repeatability and
dimensional validation on the Company's Coordinate Measuring Machine, or CMM.
The Company believes, based upon experience and customer discussions, that it is
one of a very few North American die suppliers and manufacturers that are able
to routinely, and across their product line, completely computer integrate the
mathematical database throughout the entire die design, manufacture and
validation process at their own facilities. During this automated validation
process, the tool is statistically compared to the mathematical database. Having
the optimum size and quantity of tryout presses is an important aspect of the
construction and validation process, and the Company has therefore invested
heavily to ensure its capability in this area.

    On average, 10 months elapse from the time the Company is awarded a contract
until the final set of dies is shipped to the customer. The OEMs are facing
growing pressure to reduce the time required to introduce a new car model. For
example, Chrysler has historically needed three years, on average, to introduce
a new model. However, the last small car introduced by Chrysler was introduced
in only 31 months. To meet shorter timeframes, OEMs are relying more heavily on
simultaneous engineering and integrating suppliers more closely into the design
process. This trend helps the Company by requiring more direct relationships
between the OEMs and its suppliers such as the Company.

    The steel, castings and other components utilized by the Company in the
manufacturing process are available from many different sources and the Company
is not dependent on any single source.

MARKETING AND SALES

    The Company's marketing emphasis is on Chrysler, Ford and General Motors and
their tier one suppliers. The Company maintains excellent relationships with
Chrysler, Ford and General Motors which directly accounted for about 33%, in the
aggregate, of the Company's revenues in 1998. For the year ended August 31,
1998, Chrysler, Ford, General Motors and their tier one suppliers accounted for
approximately 93% of the Company's revenues.

    With the growing use of simultaneous engineering, the Company's marketing
goal is to be assigned early to the new model Platforms. As one of only a few
technically proficient suppliers assigned to a Platform, the Company's

                                       6
<PAGE>   7

opportunity to win business for a new model is greatly enhanced. The Company
works to achieve preferred supplier status with its customers to further
increase its chances of being assigned to new model Platforms.

    Sales efforts are conducted primarily by Company's Vice President of Sales,
President, senior management and project management personnel. Frequent contact
is made with the domestic automobile manufacturers and their purchasing agents,
Platform managers and tier one suppliers. When the Company has been assigned to
a new model Platform Team, the Platform Team manager is contacted to determine
those parts and assemblies that will be assigned to various required suppliers.
During the design phase, the Company recommends process and design changes to
improve the cost and quality of the product. Generally, when the Company is
assigned to a Platform Team, orders are obtained directly and without a formal
bid process. The Company maintains a comprehensive computer database with
historical information regarding dies it has previously manufactured. This
assists the Company in quoting prices for dies and enables it to respond to most
quotation requests quickly. If the customer decides to accept the Company's
quotation, a purchase order is issued subject to price adjustments for
engineering changes requested by the customer. Where no Platform Team is
assembled, the Company bids on specific tooling assignments, and bids are
awarded on a competitive basis among a small group of qualified suppliers.

         For business done with tier one suppliers, the Company's sales process
follows a more traditional process. The Company typically receives a package or
request for quotation from the tier one supplier and is less involved in the
design process of the part to be manufactured. Bids are generally awarded based
on technological capability, price, quality and past performance.

BACKLOG AND SEASONALITY

    The Company's backlog of awarded contracts, of which all are believed to be
firm, was approximately $16.2 million and $12.1 million as of August 31, 1998
and 1997, respectively. Of the August 31, 1998 contract backlog, the Company
expects all backlog contracts will be reflected in sales during fiscal years
ended August 31, 1999 and 2000. The Company's sales of stamping dies do not
follow a seasonal pattern; however, the timing of new model introductions and
existing model restyling tooling programs are dependent on Chrysler, Ford and
General Motors and their strategy of accelerating the introduction of new
models.

COMPETITION

    Large, complex automotive stamping dies are manufactured primarily by three
supplier groups: a) domestic independent tool and die manufacturers, b) foreign
independent tool and die manufacturers, and c) captive or in-house tool and die
shops owned and operated by the OEMs.

    The independent (both domestic and foreign) tool and die manufacturers have
experienced a significant reorganization over the past five years as the
industry has consolidated. Management believes that during this period, the
independent domestic supplier base (those with sales of at least $15 million)
was reduced significantly and that fewer than 6 such independent domestic
suppliers remain today. Management believes that these 6 competitors have begun
to utilize portions of the technology utilized by the Company. Further,
significant barriers to entry reduce competition in the large-scale die market.
The industry is highly capital intensive and technically complex. Attracting and
retaining employees skilled in the use of advanced design and manufacturing
technology is a multi-year process. Finally, a new competitor would most likely
lack much of the credibility and historical customer relationships that can take
years to develop.

    Based upon the responses of 84 sheet metal die manufacturing companies to a
1996 survey by the National Tooling and Machining Association, the annual
domestic independent production of tools and dies exceeds $662,000,000, as
compared to $528,000,000 in a 1995 survey. Of those respondents only 18 reported
average annual sales in excess of $10 million. Based upon the study and the
Company's independent knowledge of its direct competitors, the Company believes
it is among the 6 largest independent suppliers and that no one supplier is
dominant.

                                       7
<PAGE>   8

    Finally, the OEMs maintain in-house, captive tool and die capacity to meet a
portion of their needs. General Motors maintains the largest captive capacity
and, based on estimates from various trade publications, supplies an estimated
75-80% of its own die construction needs. Ford produces approximately 50% and
Chrysler 25% of their own respective needs. Independent suppliers like the
Company tend to have a competitive advantage over the OEMs' in-house die shops
due to the OEMs' higher cost structure.

    The Company designs, develops and manufactures custom large scale metal
stamping die systems used in the high speed production of sheet metal stamped
parts and assemblies for the automobile industry. The Company incorporates its
knowledge of integrated computer technologies with the design and manufacture of
metal stamping die systems resulting in solutions that address the specific
manufacturing requirements of its main customers, Chrysler, Ford and General
Motors, the three largest domestic automobile manufacturers, and their tier one
suppliers of sheet metal stamped parts and assemblies.

    Management has strategically positioned the Company as one of North
America's most technologically advanced independent suppliers of metal stamping
die systems utilizing a totally computer integrated process for the design,
manufacture and validation of its products. The Company should continue to
benefit from current trends in the global automotive industry which require
continuous quality improvement, simultaneous engineering and development, and
increasing reliance on a select number of suppliers capable of utilizing
computer integrated technology to develop new automobile models. Examples of
parts made from die systems recently developed and manufactured by the Company
include; the Ford Explorer and F-Series truck bumper system, Jeep Wrangler door
panels and wheels, Chrysler Neon and mini-vans structural body components,
Chrysler LH roof panels, Ford Navigator frame systems, Ford HN 80 truck panels,
as well as aluminum body panels for the Navistar and Paccar semi-tractor
vehicle.

    By transferring the design information electronically, the Company
communicates directly with the OEMs' design and development centers regarding
specific product and manufacturing information necessary to develop a custom
manufacturing system for each respective part. This digital data base is
incorporated in each phase of the design, manufacture and inspection process for
both the prototype and production tooling systems, ensuring high quality
repeatable processes. Electronically linking the Company to the OEMs' design and
development centers enables significant reductions in product development lead
time and cost.

EMPLOYEES

    The Company's work force consists of approximately 141 full-time employees,
of which approximately 34 are salaried managerial and engineering personnel. The
balance are hourly employees engaged in manufacturing and indirect labor
support. Included among these hourly workers are approximately 102 skilled
tradesmen who are either journeymen tool and die makers or machinists. None of
the Company's employees are covered by a collective bargaining agreement. The
Company has not experienced any work stoppages and considers its relations with
its employees to be good. The Company has a discretionary contribution 401K
plan. The Company has no contingent pension liabilities arising from any defined
benefit plan.

ITEM 2.      PROPERTIES

         The Company's facilities are located in Grand Rapids, Michigan and
consist of approximately 178,000 square feet of space of which 28,000 square
feet is utilized for office, engineering and employee service functions, 98,000
square feet is dedicated to the Company's tooling production and 52,000 square
feet is under a four-year sublease to an unaffiliated tenant. Constructed in
1989, the facility is leased with a lease term of 20 years. The facility lease
provides for annual payments of $934,500 plus an escalation of base rent of 1%
for each of the first ten years and 2% for each of the second ten years. The
Company has a purchase option on the building at the fair market value beginning
in November 1996. The sublease requires annual lease payments of $224,724
commencing August 1, 1996 through July 1, 1998 and $231,468 per annum from
August 1, 1998 through July 31, 2000. The sublease also requires the subtenant
to pay 33.7% of common operating expenses of the facility. The sublease has two
renewal options for two years each with annual lease payments of $231,468 and
$238,412, respectively. During 

                                        8
<PAGE>   9

1998, the tenant exercised its option to extend the lease period until July 31,
2000. The Company exercised its option to terminate the sublease agreement on
July 31, 2000.


ITEM 3.      LEGAL PROCEEDINGS

    The Company is a plaintiff in an action against Fred Borsini, Herbert Keeler
and Durametallic Corporation, a Delaware corporation, with Kenneth K. Rieth,
Arlene Morris and Riviera Holding Company, a Michigan corporation wholly owned
by Kenneth K. Rieth, as co-plaintiffs, filed July 22, 1994, in the Kent County
Circuit Court, Grand Rapids, Michigan, Case No. 94-2809-CZ. In July of 1992, the
Company contributed machinery, equipment, inventory, work-in-process and
receivables related to the business of building plastic injection molds to a
joint venture that then became known as Leap Technologies, Inc. Defendants in
this action contributed all of the stock of a mold builder then known as Leap
Technologies, Inc. The Company contributed assets valued at $5.4 million, the
new entity assumed debts in the amount of $3.7 million, and the Company received
$1.7 million of preferred stock in the new entity. The Company alleges that the
status of the business contributed by the defendants was fraudulently
represented to it and the defendants are therefore liable to the Company for all
losses sustained as a result of the failure of the venture. The Company is
asking for return of its investment plus the additional damages it incurred in
the process of liquidating the venture. Management believes that approximately
$3,000,000 of damages has been identified, however, the damage evaluation is
incomplete. One defendant has counterclaimed for breach of representations by
the Company without specifying any amount of damages. The Company is not
currently involved in other legal proceedings other than ordinary or routine
proceedings incidental to its operations. In the opinion of management, no
existing proceedings, including the matter involving Leap Technologies, Inc.,
would have a significant effect on the financial condition, results of
operations and cash flows of the Company if determined against the Company.


ITEM 4.      SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

         No matter was submitted during the fourth quarter of the fiscal year
covered by this report to a vote of security holders through the solicitation of
proxies or otherwise.


                                     PART II

ITEM 5.      MARKET FOR REGISTRANT'S COMMON EQUITY AND RELATED SHAREHOLDER 
MATTERS

         The Company's Common Stock is traded on the American Stock Exchange
("AMEX") under the symbol RTC. The table below sets forth the high and low sales
prices as reported by AMEX during the year ended August 31, 1998.

<TABLE>
<CAPTION>
                                                       FISCAL 1998
                                                 -----------------------
                                                   HIGH           LOW
                                                 --------       --------
            <S>                                   <C>           <C>
             1st quarter.......................... 10.000        5.875
             2nd quarter.......................... 12.375        6.625
             3rd quarter.......................... 10.375        8.000
             4th quarter..........................  9.875        4.750
</TABLE>

         As of October 20, 1998, the Company's common stock was held by 42
holders of record and approximately 931 beneficial shareholders.

         The Company has not historically paid cash dividends on its Common
Stock. The Company, on October 31, 1996, declared a preferential dividend on the
shares of common stock of the Company owned by Riviera Holding Company to pay
income tax payable by Riviera Holding Company as a result of the lapse of
options by 

                                        9
<PAGE>   10

Motor Wheel Corporation to purchase common stock owned by Riviera Holding
Company and as a result of the dividend itself. In May, 1997 the Company paid
this dividend of $90,000 to Riviera Holding Company. The payment of common stock
cash dividends is within the discretion of the Company's Board of Directors,
with prior written consent of its primary lender; however, in view of the
potential working capital needs and in order to finance future growth, it is
unlikely that the Company will pay any cash dividends on its Common Stock in the
foreseeable future.

         In October, 1997, the Company issued and sold 80,000 shares of 8%
Cumulative Convertible Preferred Stock (the "Preferred Shares") at $100.00 per
share through a private placement under Regulation D of the Securities Act of
1933. With a portion of the proceeds from this sale, the Company exercised its
option to purchase all 730,000 shares of common stock held by Motor Wheel
Corporation. Under such option, the Company repurchased all the Motor Wheel
Corporation shares for $3.0 million or $4.11 per share.

         The holders of the 8% Cumulative Convertible Preferred Stock possessed
no voting rights. Cumulative dividends were to be paid at an annual rate of 8%
payable quarterly, in arrears, at a rate of $2.00 per share per quarter,
commencing December 31, 1997. Of the 80,000 Preferred Shares issued, 67,500
preferred shares were convertible into Common Stock at any time, and from time
to time, in whole or in part, for the number of shares of Common Stock per share
equal to $100 divided by $6.00. The remaining 12,500 preferred shares were
convertible into Common Stock at any time, and from time to time, in whole or in
part, for the number of shares of Common Stock per share equal to $100 divided
by $6.7375. All the Preferred Shares outstanding were automatically converted
into Common Stock when the average closing price for the Common Stock on the
American Stock Exchange for 10 consecutive trading days is equal to or greater
than $10 per share. The Company was not required to issue fractional shares in
connection with any conversion and a cash payment shall be made in lieu thereof.
On January 9, 1998, the Company registered 1,461,529 shares of Common Stock
under the Securities Act of 1933. These common shares were issuable upon
conversion of the its 8% Cumulative Convertible Preferred Stock. On January 10,
1998, the Company sent notice to all holders of the 8% Cumulative Convertible
Preferred Stock that all such preferred shares outstanding would be
automatically converted into Common Stock on or before February 11, 1998, under
the mandatory conversion provision which requires mandatory conversion when the
average closing price for the Common Stock on the American Stock Exchange is
$10.00 per share (which occurred during the trading period of November 20 and
December 4, 1997). On February 11, 1998, all 80,000 shares of 8% Cumulative
Convertible Preferred Stock was converted into 1,310,499 shares of registered
Common Stock.

ITEM 6.      SELECTED FINANCIAL DATA

         Information  required by this Item 6 is  incorporated  by reference to 
page 32 and 33 of the  Company's  1998 Annual Report to Shareholders filed as 
Exhibit 13 hereto.


ITEM 7.      MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND 
RESULTS OF OPERATIONS

         Information required by this Item 7 is incorporated by reference to
pages 34 - 37 of the Company's 1998 Annual Report to Shareholders filed as
Exhibit 13 hereto.


ITEM 8.      FINANCIAL STATEMENTS & SUPPLEMENTARY DATA

         The Registrant hereby incorporates the financial statements required by
this Item 8 by reference to Item 14(a)(1) hereof, and the supplementary
financial information required by this Item 8 by reference to page 38 - 51 of
the Company's 1998 Annual Report to Shareholders filed as Exhibit 13 hereto.


                                       10
<PAGE>   11

ITEM 9.      CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND 
FINANCIAL DISCLOSURE

         None.

                                    PART III

         The Registrant hereby incorporates the information required by Form
10-K, Items 10-13 by reference to the Registrant's definitive proxy statement
for its 1998 annual meeting of shareholders which was filed with the Commission
prior to November 23, 1998.


                                     PART IV

ITEM 14.     EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

         (a) The following documents are filed as a part of this report:

1.                Financial Statements - The following financial statements and
         the report of independent auditors set forth on pages 38 - 51 of the
         Company's 1998 Annual Report to Shareholders filed as Exhibit 13 hereto
         are incorporated by reference in this Annual Report on Form 10-K.

                  Balance Sheets as of August 31, 1998 and 1997
                  Notes to Financial Statements

                  For each of the three years in the period ended August 31, 
                  1998:
                           Statements of Common Shareholders' Equity
                           Statement of Operations
                           Statements of Cash Flows

                  Report of Independent Auditors

2.       Financial Statement Schedules - No such schedules are included because
         of the absence of the conditions under which they are required, or
         because the information called for is included in the financial
         statements or notes thereto.

3.       Exhibits


            3(a)    Amended and Restated Articles of Incorporation of the
                    Registrant.

            3(b)    Bylaws of the Registrant (incorporated by reference to
                    Exhibit 3(b) of the Registrant's Amendment No. 1 to Form
                    S-1, Registration No. 333-14187, filed January 8, 1997).

            4(a)    Specimen Common Stock of Registrant (incorporated by
                    reference to Exhibit 4(a) of the Registrant's Form S-1,
                    Registration No. 333-14187, filed October 15, 1996).

            4(b)    Representative's Warrant Agreement (incorporated by
                    reference to Exhibit 4(b) of the Registrant's Post-effective
                    Amendment No. 1 to Form S-1, Registration No. 333-14187,
                    filed March 14, 1997).

            4(c)    Consulting Agreement and Plan of Compensation dated March 4,
                    1997 between the Registrant and John T. Moran (incorporated
                    by reference to Exhibit 4(c) of the Registrant's Form S-8,
                    Registration No. 333-29249, filed June 13, 1997).


                                       11
<PAGE>   12

            4(d)    Form of Warrant Agreement (including form of Warrant)
                    (incorporated by reference to Exhibit 4(d) of the
                    Registrant's Form S-8, Registration No. 333-29249, filed
                    June 13, 1997).

              9     Shareholder Agreement and related Stock Option Agreement
                    between Riviera Holding Company and Motor Wheel Corporation
                    (incorporated by reference to Exhibit 9 of the Registrant's
                    Amendment No. 1 to Form S-1, Registration No. 333-14187,
                    filed January 8, 1997).

            10(a)   1996 Incentive Stock Option Plan of Registrant.

            10(b)   Employment  Agreement of Kenneth K. Rieth  (incorporated  by
                    reference to Exhibit 10(b) of the Registrant's Amendment No.
                    1 to Form S-1, Registration No. 333-14187, filed January 8, 
                    1997).

            10(e)   Lease Agreement dated November 1, 1988 between Registrant
                    and Greenbrook Limited Partners/Riviera regarding industrial
                    facilities at 5460 Executive Parkway SE, Grand Rapids,
                    Michigan (incorporated by reference to Exhibit 10(e) of the
                    Registrant's Form S-1, Registration No. 333-14187, filed
                    October 15, 1996).

            10(f)   Commitment from LaSalle National Bank (incorporated by
                    reference to Exhibit 10(f) of the Registrant's Amendment No.
                    2 to Form S-1, Registration No. 333-14187, filed February
                    24, 1997).

            10(g)   NBD Bank Credit Agreement  (incorporated by reference to 
                    Exhibit 10(g) of the Registrant's  Amendment No. 2 to Form 
                    S-1, Registration No. 333-14187, filed February 24, 1997).

            10(h)   Assignment of Stock Options between Riviera Holding Company
                    and Registrant (incorporated by reference to Exhibit 10(h)
                    of the Registrant's Amendment No. 2 to Form S-1,
                    Registration No. 333-14187, filed February 24, 1997).

            10(i)   Loan Agreement, Revolving Loan Note, Term Note and Security
                    Agreement between Registrant and LaSalle National Bank dated
                    March 7, 1997 (incorporated by reference to Exhibit 10(i) of
                    the Registrant's Form 10-Q, filed April 17, 1997).

            10(j)   Assignment of Life Insurance  Policy to NBD Bank dated March
                    3, 1997  (incorporated by reference to Exhibit 10(j) of the 
                    Registrant's Form 10-Q, filed April 17, 1997).

            10(k)   Assignment  of Claim to NBD Bank dated March 3, 1997  
                    (incorporated  by reference  to Exhibit  10(k) of the 
                    Registrant's Form 10-Q, filed April 17, 1997).

            10(l)   Loan Agreement, Revolving Line of Credit Loan Note, Existing
                    Equipment Term Loan Note, Non-Revolving Equipment Line of
                    Credit Loan Note, Security Agreement and Assignment of Life
                    Insurance Policy as Collateral between Registrant and Old
                    Kent Bank dated June 12, 1997 (incorporated by reference to
                    Exhibit 10(l) of the Registrant's Form 10K, filed November
                    26, 1997).

            10(m)   Amendments number 1, 2, 3, and 4 between Registrant and Old
                    Kent Bank dated December 31, 1997, February 15, 1998, August
                    14, 1998 and August 14, 1998, respectively.

            10(n)   Release of Policy as Collateral Security from NBD Bank dated
                    December 2, 1997.

            10(o)   Assignment of Life Insurance Policy as Collateral Security 
                    to Old Kent Bank dated July 23, 1998.

            10(p)   1998 Key Employee Stock Option Plan dated November 2, 1998

             13     1998 Annual Report to Shareholders.


                                       12
<PAGE>   13

             21     Subsidiaries - None

             27     Financial Data Schedule.

         (b).     No Reports on Form 8-K were filed in 1998.


                                       13
<PAGE>   14

                                   SIGNATURES

         Pursuant to the requirement of Section 13 or 15(d) of the Securities
and Exchange Act of 1934 the Registrant has duly caused this report to be signed
on its behalf by the undersigned, thereunto duly authorized.





Dated:   November 23, 1998       RIVIERA TOOL COMPANY


                                 By: /s/ Kenneth K. Rieth
                                     --------------------
                                     Kenneth K. Rieth, Principal Executive 
                                     Officer

                                     and

                                 By: /s/ Peter C. Canepa
                                     -------------------
                                     Peter C. Canepa, Principal Financial 
                                     and Accounting Officer


         Pursuant to the requirements of the Securities Exchange Act of 1934,
this report has been signed below on the 23rd day of November, 1998, by the
following persons on behalf of the Company and in the capacities indicated.

         Each Director of the Company whose signature appears below hereby
appoints Kenneth K. Rieth and Peter C. Canepa, and each of them individually, as
his attorney-in-fact to sign in his name and on his behalf as a Director of the
Company, and to file with the Commission any and all amendments to this report
on Form 10-K to the same extent and with the same effect as if done personally.


/s/ Leonard H. Wood                                /s/ Kenneth K. Rieth
-------------------                                --------------------
Leonard H. Wood, Director                          Kenneth K. Rieth, Director

/s/ John C. Kennedy                                /s/ Daniel W. Terpsma
-------------------                                ---------------------
John C. Kennedy, Director                          Daniel W. Terpsma, Director

/s/ Thomas H. Highley      
---------------------      
Thomas H. Highley, Director


SUPPLEMENTAL INFORMATION TO BE FURNISHED WITH REPORTS FILED PURSUANT TO SECTION
15(d) OF THE ACT BY REGISTRANTS WHICH HAVE NOT REGISTERED SECURITIES PURSUANT TO
SECTION 12 OF THE ACT.

Not Applicable.


                                       14
<PAGE>   15
                               INDEX TO EXHIBITS

EXHIBIT NO.              DESCRIPTION
-----------              -----------
3(a)      Amended and Restated Articles of Incorporation of the Registrant.

3(b)      Bylaws of the Registrant (incorporated by reference to Exhibit 3(b) 
          of the Registrant's Amendment No. 1 to Form S-1, Registration No. 
          333-14187, filed January 8, 1997).

4(a)      Specimen Common Stock of Registrant (incorporated by reference to 
          Exhibit 4(a) of the Registrant's Form S-1, Registration No. 
          333-14187, filed October 15, 1996).

4(b)      Representative's Warrant Agreement (incorporated by reference to 
          Exhibit 4(b) of the Registrant's Post-effective Amendment No. 1 to 
          Form S-1, Registration No. 333-14187, filed March 14, 1997).

4(c)      Consulting Agreement and Plan of Compensation dated March 4, 1997 
          between the Registrant and John T. Moran (incorporated by reference to
          Exhibit 4(c) of the Registrant's Form S-8, Registration No. 333-29249,
          filed June 13, 1997).

4(d)      Form of Warrant Agreement (including form of Warrant) (incorporated 
          by reference to Exhibit 4(d) of the Registrant's Form S-8, 
          Registration No. 333-29249, filed June 13, 1997).

 9        Shareholder Agreement and related Stock Option Agreement between 
          Riviera Holding Company and Motor Wheel Corporation (incorporated by 
          reference to Exhibit 9 of the Registrant's Amendment No. 1 to Form 
          S-1, Registration No. 333-14187, filed January 8, 1997).

10(a)     1996 Incentive Stock Option Plan of Registrant.

10(b)     Employment Agreement of Kenneth K. Rieth (incorporated by reference 
          to Exhibit 10(b) of the Registrant's Amendment No. 1 to Form S-1, 
          Registration No. 333-14187, filed January 8, 1997).

10(e)     Lease Agreement dated November 1, 1998 between Registrant and 
          Greenbrook Limited Partners/Riviera regarding industrial facilities 
          at 5460 Executive Parkway SE, Grand Rapids, Michigan (incorporated by 
          reference to Exhibit 10(e) of the Registrant's Form S-1, Registration 
          No. 333-14187, filed October 15, 1996).

10(f)     Commitment from LaSalle National Bank (incorporated by reference to 
          Exhibit 10(f) of the Registrant's Amendment No. 2 to Form S-1, 
          Registration No. 333-14187, filed February 24, 1997).

10(g)     NBD Bank Credit Agreement (incorporated by reference to Exhibit 10(g) 
          of the Registrant's Amendment No. 2 to Form S-1, Registration No. 
          333-14187, filed February 24, 1997).

10(h)     Assignment of Stock Options between Riviera Holding Company and 
          Registrant (incorporated by reference to Exhibit 10(h) of the 
          Registrant's Amendment No. 2 to Form S-1, Registration No. 333-14187, 
          filed February 24, 1997).

10(i)     Loan Agreement, Revolving Loan Note, Term Note and Security Agreement 
          between Registrant and LaSalle National Bank dated March 7, 1997 
          (incorporated by reference to Exhibit 10(i) of the Registrant's Form 
          10-Q, filed April 17, 1997).

10(j)     Assignment of Life Insurance Policy to NBD Bank dated March 3, 1997 
          (incorporated by reference to Exhibit 10(j) of the Registrant's Form 
          10-Q, filed April 17, 1997).

<PAGE>   16
                               INDEX TO EXHIBITS

EXHIBIT NO.              DESCRIPTION
-----------              -----------
10(k)     Assignment of Claim to NBD Bank dated March 3, 1997  (incorporated by
          reference to Exhibit 10(k) of the Registrant's Form 10-Q, filed April 
          17, 1997).

10(l)     Loan Agreement, Revolving Line of Credit Loan Note, Existing 
          Equipment Term Loan Note, Non-Revolving Equipment Line of Credit Loan 
          Note, Security Agreement and Assignment of Life Insurance Policy as 
          Collateral between Registrant and Old Kent Bank dated June 12, 1997 
          (incorporated by reference to Exhibit 10(l) of the Registrant's Form 
          10K, filed November 26, 1997).

10(m)     Amendments number 1, 2, 3, and 4 between Registrant and Old Kent Bank 
          dated December 31, 1997, February 15, 1998, August 14, 1998 and 
          August 14, 1998, respectively.

10(n)     Release of Policy as Collateral Security from NBD Bank dated December 
          2, 1997.

10(o)     Assignment of Life Insurance Policy as Collateral Security to Old 
          Kent Bank dated July 23, 1998.

10(p)     1998 Key Employee Stock Option Plan dated November 2, 1998.

 13       1998 Annual Report to Shareholders.

 21       Subsidiaries -- None

 27       Financial Data Schedule.