<PAGE>   1
                                    FORM 10-Q

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                 Quarterly Report Under Section 13 or 15 (d) of
                       The Securities Exchange Act of 1934

(Mark One)
[X]     QUARTERLY REPORT PURSUANT TO SECTION 13 OR 14 (d) OF
        THE SECURITIES EXCHANGE ACT OF 1934
        For the quarterly period ended December 31, 1999

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

                           Commission File No. 0-7770

                            MCCLAIN INDUSTRIES, INC.
             (Exact name of registrant as specified in its charter)

Michigan                                             38-1867649
 State of Incorporation                         IRS Employer I.D. No.

                               6200 Elmridge Road
                        Sterling Heights, Michigan 48310
                                 (810) 264-3611
          (Address of principal executive offices and telephone number)

     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 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 the number of shares outstanding of each of the issuer's classes
of common stock as of February 4, 2000.

Common Stock, No Par Value                             4,637,217
--------------------------                          ----------------
         Class                                      Number of Shares



                                    1 of 13



<PAGE>   2

          PART I. FINANCIAL INFORMATION

Item 1.  Financial Statements

                    McCLAIN INDUSTRIES, INC. AND SUBSIDIARIES
                      CONDENSED CONSOLIDATED BALANCE SHEETS


<TABLE>
<CAPTION>


                                      ASSETS                             DECEMBER 31,     SEPTEMBER 30,
                                                                             1999             1999
                                                                          (UNAUDITED)
                                                                         ------------     ------------
<S>                                                                      <C>               <C>
CURRENT ASSETS
     Cash and cash equivalents                                           $  1,854,084      $  1,908,397
     Accounts receivable, (Net)                                            15,859,134        20,140,166
     Inventories                                                           65,019,607        63,281,785
     Net investment in sales-type leases, current portion                   7,100,000         5,900,000
     Prepaid expenses                                                         959,167           237,129
                                                                         ------------      ------------

TOTAL CURRENT ASSETS                                                       90,791,992        91,467,477
                                                                         ------------      ------------

Property, plant and equipment, net                                         22,997,913        23,236,170
                                                                         ------------      ------------

Net investment in sales-type leases, net of
     current portion                                                       13,811,651        12,871,973
                                                                         ------------      ------------

Other assets                                                                2,570,069         2,348,369
                                                                         ------------      ------------

Total other assets                                                        130,171,625       129,923,989
                                                                         ============      ============

                           LIABILITIES AND STOCKHOLDERS' INVESTMENT
CURRENT LIABILITIES
     Accounts payable                                                    $ 23,977,457      $ 21,775,139
     Current portion of long-term debt                                      4,450,000         4,450,000
     Accrued expenses                                                       4,541,618         4,682,156
     Federal and state income taxes                                            43,745         1,870,217
                                                                         ------------      ------------

TOTAL CURRENT LIABILITIES                                                  33,012,820        32,777,512

Long-term debt, net of current portion                                     62,578,021        62,648,684

Product liability                                                           1,136,932         1,406,828

Deferred income taxes                                                       2,200,000         2,200,000
                                                                         ------------      ------------

TOTAL LIABILITIES                                                          98,927,773        99,033,024
                                                                         ------------      ------------

STOCKHOLDERS' INVESTMENT                                                   31,243,852        30,890,965
                                                                         ------------      ------------

TOTAL LIABILITIES AND STOCKHOLDERS' INVESTMENT                           $130,171,625      $129,923,989
                                                                         ============      ============

</TABLE>

See notes to condensed consolidated financial statements

                                    2 of 13


<PAGE>   3

                    MCCLAIN INDUSTRIES, INC. AND SUBSIDIARIES
                 CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS
                                    UNAUDITED

<TABLE>
<CAPTION>

                                                THREE MONTHS ENDED
                                                    DECEMBER 31,
                                         -------------------------------
                                             1999               1998
                                         ------------       ------------
<S>                                      <C>                <C>
Net sales                                $ 29,592,618       $ 27,156,906

Cost of sales                              24,005,434         22,314,809
                                         ------------       ------------

GROSS PROFIT                                5,587,184          4,842,097

Selling, general and administrative
     expenses                               3,929,930          3,446,543
                                         ------------       ------------

INCOME FROM OPERATIONS                      1,657,254          1,395,554
                                         ------------       ------------

OTHER INCOME (EXPENSE)
     Interest expense                      (1,258,254)          (863,076)
     Interest income                          468,333            363,939
     Other, net                              (142,063)           (45,631)
                                         ------------       ------------

OTHER EXPENSE - NET                          (931,984)          (544,768)
                                         ------------       ------------

INCOME (LOSS) BEFORE INCOME TAXES             725,270            850,786

Income taxes (benefit)                        247,000            289,000
                                         ------------       ------------

NET INCOME (LOSS)                        $    478,270       $    561,786
                                         ============       ============

Net income (loss) per share:
     Basic                               $       0.10       $       0.12
                                         ============       ============
     Assuming dilution                   $       0.10       $       0.12
                                         ============       ============
</TABLE>




See notes to condensed consolidated financial statements

                                     3 of 13



<PAGE>   4




                    MCCLAIN INDUSTRIES, INC. AND SUBSIDIARIES
                 CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS
                                    UNAUDITED


<TABLE>
<CAPTION>

                                                                                              THREE MONTHS ENDED
                                                                                                  DECEMBER 31,
                                                                                        -----------------------------
                                                                                            1999              1998
                                                                                        -----------       -----------
<S>                                                                                     <C>               <C>
CASH FLOWS FROM OPERATING ACTIVITIES:
     Net income                                                                         $   478,270       $   561,486
     Adjustments to reconcile net income to
     net cash provided by operating activities
       Depreciation and amortization                                                        843,953           800,753
       Common stock issued to directors for services                                          7,493                 0
       Net changes in operating assets and liabilities which provided (used)
       cash:
         Current assets excluding cash & cash equivalents                                   621,172         1,746,712
         Other assets                                                                    (1,295,088)         (306,331)
         Accounts payable                                                                 2,202,318        (2,557,315)
         Accrued expenses                                                                  (140,538)          243,404
         Federal and state income taxes                                                  (1,826,472)         (513,994)
                                                                                        -----------       -----------
NET CASH (USED) PROVIDED BY OPERATING ACTIVITIES                                            891,108           (25,285)
                                                                                        -----------       -----------

CASH FLOWS FROM INVESTING ACTIVITIES:
     Purchases of plant and equipment                                                      (471,987)         (324,870)
     Payments (made on) received from liabilities assumed upon the
     Galion acquisition                                                                    (269,896)          721,409
                                                                                        -----------       -----------
NET CASH USED IN INVESTING ACTIVITIES                                                      (741,883)          396,539
                                                                                        -----------       -----------

CASH FLOWS FROM FINANCING ACTIVITIES:
     Principal reduction of long term debt                                                  (70,663)       (1,570,778)
     Sale of common stock under stock option plan                                                 0                 0
     Repurchase of common stock                                                            (132,875)                0
                                                                                        -----------       -----------
NET CASH PROVIDED BY FINANCING ACTIVITIES                                                  (203,538)       (1,570,778)
                                                                                        -----------       -----------

NET (DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS                                        (54,313)       (1,199,524)
                                                                                        -----------       -----------

Cash and cash equivalents, beginning of year                                              1,908,397         1,924,006
                                                                                        -----------       -----------
CASH AND CASH EQUIVALENTS, END OF YEAR                                                  $ 1,854,084       $   724,482
                                                                                        ===========       ===========
</TABLE>


See notes to condensed consolidated financial statements

                                     4 of 13
<PAGE>   5

                            MCCLAIN INDUSTRIES, INC.

             NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED)
                      THREE MONTHS ENDED DECEMBER 31, 1999

1.       Basis of Presentation

         The accompanying unaudited Consolidated Financial Statements of McClain
         Industries, Inc. and subsidiaries (the "Company") have been prepared in
         accordance with generally accepted accounting principles for interim
         financial information and with the instructions to Form 10-Q and Rule
         10-01 of Regulation S-X. Accordingly, such Statements do not include
         all of the information and footnotes required by generally accepted
         accounting principles for complete financial statements. In the opinion
         of management, all adjustments consisting of normal recurring items
         considered necessary for a fair presentation have been included.
         Operating results for the three-month period ended December 31, 1999
         are not necessarily indicative of the results that may be expected for
         the year ending September 30, 2000. For further information, refer to
         the Consolidated Financial Statements and footnotes thereto included in
         the Company's annual report on Form 10-K for the year ended September
         30, 1999.

2.       Inventories

         Inventories at December 31, 1999 and September 30, 1999 are summarized
         as follows:


<TABLE>
<CAPTION>

                                             (Unaudited)
                                            December 31, 1999    September 30, 1999
                                            -----------------    ------------------
         <S>                              <C>                       <C>
         Materials and Supplies             $  21,660,285             $  19,416,535
         Work in Process                        6,016,746                 5,555,977
         Finished Goods                        12,434,607                11,120,913
         Chassis                               24,907,969                27,188,360
                                            -------------             -------------
                                            $  65,019,607             $  63,281,785
                                            -------------             -------------
</TABLE>

3.       Earnings per Common Share and Common Equivalent Share:

         Earnings per share are computed using the weighted average number of
         common shares outstanding during the year. The Company adopted
         Statement of Financial Accounting Standards ("SFAS") No. 128, "Earnings
         Per Share", effective September 30, 1998. This statement requires a
         dual presentation and reconciliation of "basic" and "diluted" per share
         amounts. Diluted reflects the potential dilution of all common stock
         equivalents. At December 31, 1999 and 1998 options to purchase 258,337
         and 264,464 shares, respectively, were excluded from the computation of
         earnings per share because the options' exercise prices were greater
         than the average market price of the common shares.

                                     5 of 13


<PAGE>   6





                            MCCLAIN INDUSTRIES, INC.

             NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED)
                      THREE MONTHS ENDED DECEMBER 31, 1999


4.       Depreciation

         For the three months ended December 31, 1999 and 1998, depreciation
         charges were $710,242 and $686,411, respectively. Accumulated
         depreciation totaled $21,823,184 and $21,046,447 at December 31, 1999
         and September 30, 1999, respectively.

5.       Contingencies

         Product Liability

         As a manufacturer of industrial products, the Company is occasionally
         subjected to various product liability claims. Such claims typically
         involve personal injury or wrongful death associated with the use or
         misuse of the Company's products. The Company is currently defending
         certain legal proceedings involving allegations of product liability
         relating to products manufactured and sold by the Company.
         Historically, such claims have not resulted in material losses to the
         Company in any one year, and the Company maintains product liability
         insurance in amounts believed by management to be adequate.

         McClain E-Z Pack, Inc., as successor to Galion Holding Company (GHC),
         pursuant to an indemnification it provided to the seller in connection
         with GHC's July 1992 acquisition of the Galion operations, is currently
         defending a number of legal proceedings involving product liability
         claims arising out of products manufactured and sold prior to the
         acquisition. These claims are covered by insurance and many of these
         cases have been settled. In addition, the acquisition agreement called
         for the seller to share in the payment of certain costs related to the
         defense of these cases. On December 29, 1998 the Company reached a
         settlement agreement with the seller, the terms of which called for the
         Company to release the seller from its obligations related to product
         liability claims under the Galion acquisition agreement in exchange for
         a cash payment of $1,050,000.

         A reserve to provide for these product claims was established at the
         acquisition date. Since many of the cases have been settled and
         insurance coverage exists, management believes that the ongoing costs
         to defend these claims will not exceed the amount accrued on the
         accompanying consolidated balance sheet at December 31, 1999.
         Nevertheless, it is not possible to predict the ultimate outcome of any
         product liability claim, and any such claim not fully covered by
         insurance, as well as adverse publicity from a product claim, could
         have a material adverse effect on the Company.

                                     6 of 13




<PAGE>   7




                            MCCLAIN INDUSTRIES, INC.

             NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED)
                      THREE MONTHS ENDED DECEMBER 31, 1999


         Environmental Matters

         The Company's operations are subject to extensive federal, state and
         local regulation under environmental laws and regulations concerning,
         among other things, emissions into the air, discharges into the waters
         and the generation, handling, storage, transportation, treatment and
         disposal of waste and other materials. Inherent in manufacturing
         operations and in owning real estate is the risk of environmental
         liabilities as a result of both current and past operations, which
         cannot be predicted with certainty. The Company has incurred and will
         continue to incur costs, on an ongoing basis, associated with
         environmental regulatory compliance in its business.

         Labor Union Matters

         Certain of the Company's hourly employees are represented by various
         labor unions pursuant to collective bargaining agreements which expire
         between June 2000 and November 2002.

         On February 23, 1995, the National Labor Relations Board (NLRB)
         conducted an election in response to a petition filed by a local union
         (Union) to represent the hourly employees at the Company's Macon,
         Georgia plant. The ballots of certain employees were challenged as
         ineligible. The Union filed charges asserting that the Company
         committed various unfair labor practices, which affected the election
         results, and that the challenged ballots should be counted. On October
         17, 1996, the NLRB upheld the unfair labor practice charges and on
         November 5, 1996, the NLRB determined that the results of the election
         were in favor of the Union. The Company continues to vigorously defend
         against the unfair labor practice allegations. The Company does not
         believe a final decision upholding the Union certification or the
         unfair labor practice charges would have a material adverse effect on
         the Company. The Company believes that relations with the hourly
         employees at McClain of Georgia are generally satisfactory. There have
         been no work stoppages due to labor difficulties.

         Other Legal Matters

         The Company is also involved in routine litigation incidental to its
         business. Management believes that the resolution of these matters will
         not materially affect the consolidated financial statements.


                                     7 of 13


<PAGE>   8


                            MCCLAIN INDUSTRIES, INC.

             NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED)
                      THREE MONTHS ENDED DECEMBER 31, 1999


6.       Year 2000 Compliance

         The Company did not experience any significant disruptions in its
         operations that were related to the Year 2000 issue.


7.       Segment Information

         During fiscal 1999, the Company adopted Statement of Financial
         Accounting Standards (SFAS) No. 131 "Disclosures About Segments of an
         Enterprise and Related Information. This statement requires financial
         information to be reported on the basis that management uses for
         evaluating segment performance and making operating decisions.

         The Company operates in three principal operating segments 1)
         Manufactured Equipment, 2) Truck Chassis Sales, and 3) Leasing
         Operations. The accounting policies of the reportable segments are the
         same as those described in Note 1. Management evaluates the performance
         of its operating segments separately to individually monitor the
         different factors affecting performance. The Company measures the
         performance of its operating segments based on net revenue and
         operating income. Income taxes are managed on a Company-wide basis.
         Segment performance is also evaluated based on profit or loss before
         income taxes.

















                                     8 of 13





<PAGE>   9


                    MCCLAIN INDUSTRIES, INC. AND SUBSIDIARIES

             NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED)
                      THREE MONTHS ENDED DECEMBER 31, 1999

Information regarding the Company's operating segments follows:

<TABLE>
<CAPTION>


                                                  Manufacturing              Truck           Leasing
                                                   Operations                Group          Operations             Totals
                                                   -----------            -----------      -------------         -----------
<S>                                                <C>                   <C>               <C>                  <C>
           1999
           ----
              Net sales                            $22,848,062           $6,744,556                  $0          $29,592,618
              Lease revenues                                 0                    0           1,188,257            1,188,257
              Operating income (loss)                1,360,155               60,415             236,684            1,657,254
              Interest expense, net                    615,737              414,063             228,454            1,258,254
              Income (loss) before
                  income taxes                         851,234             (362,648)            236,684              725,270
              Identifiable assets                   82,595,945           25,310,013          22,265,667          130,171,625
              Capital expenditures                     471,987                    0                   0              471,987
              Depreciation and
                  amortization                         843,953                    0                   0              843,953

           1998
           ----
              Net sales                            $19,922,446           $7,234,460                  $0          $27,156,906
              Lease revenues                                 0                    0             764,649              764,649
              Operating income (loss)                  895,902              307,183             192,469            1,395,554
              Interest expense, net                    709,788                    0             153,288              863,076
              Income (loss) before
                  income taxes                         351,134              307,183             192,469              850,786
              Identifiable assets                   79,750,713            6,670,251          10,710,215           97,131,179
              Capital expenditures                     324,870                    0                   0              324,870
              Depreciation and
                  amortization                         800,753                    0                   0              800,753

</TABLE>



















                                    9 of 13






<PAGE>   10



                            MCCLAIN INDUSTRIES, INC.

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

Overview

         The following discussion should be read in conjunction with the
condensed consolidated financial statements, including the notes thereto,
appearing elsewhere in this report.

         Selected financial data for the Company for the periods indicated:


<TABLE>
<CAPTION>

                                                               (Unaudited)
                                                            Three Months Ended
                                                                December 31,
                                                       1999                   1998
                                                    -------------       ------------------
<S>                                                  <C>                   <C>
Net Sales                                            $29,592,618           $27,156,906

Net Income                                               478,270               561,786

Net Earnings Per Common
 Share (Basic and Diluted)                           $       .10           $       .12
</TABLE>

<TABLE>
<CAPTION>


                                                    (Unaudited)
                                                        As of                      As of
                                                     December 31,               September 30,
                                                        1999                        1999
                                                    -------------              --------------
<S>                                                  <C>                       <C>
  Working Capital                                    $57,779,172               $ 58,689,965

  Total Assets                                       130,171,625                129,923,989

  Long-Term Debt                                      62,578,021                 62,648,684

  Stockholder's Investment                            31,243,852                 30,890,966

  Common Shares Outstanding
  (Basic and Diluted)                                  4,637,585                  4,673,027

  Current Ratio                                           2.75:1                     2:79:1
  Long-Term Debt to Equity
  Stockholders' Investment                                2.03:1                     2.03:1
</TABLE>

                                    10 of 13




<PAGE>   11


                            MCCLAIN INDUSTRIES, INC.

  The following table presents, as a percentage of net sales, certain selected
financial data for the Company for the periods indicated:

<TABLE>
<CAPTION>

                                                                     (Unaudited)
                                                                 Three Months Ended
                                                                     December 31,
                                                               1999              1998
                                                              -------------------------

<S>                                                           <C>               <C>
Net Sales                                                     100.00%           100.00%
Cost of Sales                                                  81.12             82.17
                                                              -------------------------

Gross Profit                                                   18.88             17.83

Selling, General &
Administrative Expenses                                        13.28             12.69
                                                              ------------------------

Operating Income                                                5.60              5.14

Other Expenses                                                 (3.15)            (2.01)
                                                              ------------------------

Income before Income Taxes                                      2.45              3.13

Provision for Income Taxes                                     (0.83)            (1.06)
                                                              -------------------------

Net Income                                                      1.62%             2.07%
                                                              =========================
</TABLE>















                                    11 of 13





<PAGE>   12


                            MCCLAIN INDUSTRIES, INC.

                 DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION


         Net sales increased 9.0% to $29.6 million for the quarter ended
December 31, 1999 (Quarter 1999) from $27.2 million for the quarter ended
December 31, 1998 (Quarter 1998). The increase was due primarily to strong sales
of the various refuse equipment products manufactured by the Company's McClain
E-Z Pack subsidiary, which were offset by a slight reduction in the sales of
McClain Truck Group. Sales for McClain E-Z Pack increased 15.5% or $2.4 million
for the Quarter 1999 over the Quarter 1998. While McClain Truck sales decreased
7.3% or $0.5 million during the Quarter 1999 compared to the Quarter 1998. Sales
of the Company's other product lines were flat for the Quarter 1999 compared to
the Quarter 1998. The sales of the McClain Truck division accounted for 22.8% of
the Company's sales for the Quarter 1999 compared to 26.7% of the Company's
sales for the Quarter 1998.

         Cost of goods sold decreased to 81.12% for the Quarter 1999 from 82.17%
for the Quarter 1998. The gross profit margin on manufactured products increased
to 22.9% for the Quarter 1999 compared to 22.8% for the Quarter 1998. The gross
profit margin for McClain Truck increased to 5.4% for the Quarter 1999 from 4.9%
for the Quarter 1998.

         Selling, General & Administrative Expenses increased slightly to 13.28%
of net sales for the Quarter 1999 from 12.6% of net sales for the Quarter 1998.

         The Company had working capital of $57.9 million at December 31, 1999
compared to $58.7 million at September 30, 1999. The ratio of current assets to
current liabilities was 2.75:1 at December 31, 1999 and 2.79:1 at September 30,
1999. The Company's cash and cash equivalents totaled $1.9 million at December
31, 1999. Cash flows provided by operations were $0.9 million for the three
months ended December 31, 1999.















                                    12 of 13


<PAGE>   13




                                   SIGNATURES




         Pursuant to the requirements 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.









                                      McCLAIN INDUSTRIES, INC.

Date:     February 4, 2000            By:        Kenneth D. McClain
          ---------------------------       ---------------------------
                                      Kenneth D. McClain, President

Date:     February 4, 2000            By:        Mark S. Mikelait
          ---------------------------       ---------------------------
                                      Mark S. Mikelait, Treasurer

















                                    13 of 13

<PAGE>   14




                                      Exhibit Index
                                      -------------
<TABLE>
<CAPTION>
Exhibit No.                         Description
-----------                         -----------
<S>                                 <C>
     27                             Financial Data Schedule

</TABLE>