EXHIBIT 3.21

                          CERTIFICATE OF INCORPORATION

                                       OF

                              WHEEL ASSEMBLIES INC.

      FIRST. The name of the corporation is:

                              WHEEL ASSEMBLIES INC.

      SECOND. The address of its registered office in the State of Delaware is
Corporation Trust Center, 1209 Orange Street in the City of Wilmington, County
of New Castle. The name of its registered agent at such address is The
Corporation Trust Company.

      THIRD. The nature of the business, or objects or purposes, to be
conducted, transacted, promoted or carried on by the corporation are:

(a)   To subscribe for, purchase, invest in, own, hold, sell and otherwise
      generally deal in and with equity securities of every kind and description
      of any corporation, joint stock company, association, limited partnership,
      general partnership, firm, trust, joint venture enterprise, syndicate,
      consortium, combination or entity; to acquire or become interested in any
      such securities by original subscription, underwriting, participation in
      syndicates or otherwise; and to exercise any and all rights, powers, and
      privileges of individual ownership or interest in respect of any such
      securities, including the right to vote thereon and otherwise act with
      respect thereto;

(b)   To acquire, by purchase, subscription or otherwise, and to receive, own,
      guarantee, sell, assign, exchange, transfer, mortgage, pledge or otherwise
      dispose of or deal in or with any scrip, warrants, rights, bonds,
      debentures, notes, trust receipts, voting trust certificates, and any and
      all other securities, obligations, choses in action, evidence of
      indebtedness or interests issued or created by any corporation, joint
      stock company, association, limited partnership, general partnership,
      firm, trust, joint venture enterprise, syndicate, consortium, combination
      or entity or person, public or private or by the government of the United
      States of America, or by any foreign government, or by any state,
      territory, province, municipality or other political subdivision or by any
      governmental agency, and as owner thereof to possess and exercise all the
      rights, powers and privileges of ownership, including the right to execute
      consents and vote thereon, and to do any and all acts and things necessary
      or advisable for the preservation, protection, improvement and enhancement
      in value thereof;

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(c)   To borrow or raise money for any of the purposes of the corporation and,
      from time to time without limit as to amount, to draw, make, accept,
      endorse, execute and issue promissory notes, drafts, bills of exchange,
      warrants, bonds, debentures and other negotiable or non-negotiable
      instruments and evidences of indebtedness, and to secure the payment of
      any thereof and of the interest thereon by mortgage upon or pledge,
      conveyance or assignment in trust of the whole or any part of the property
      of the corporation, whether at the time owned or thereafter acquired, and
      to sell, pledge or otherwise dispose of, and to reacquire and otherwise
      deal in, such obligations of the corporation;

(d)   To participate as an equity investor in the institution, promotion and
      organization of financial, manufacturing, industrial, natural resource
      exploration and development and other business concerns, firms,
      associations, corporations or other forms of enterprises; and to purchase,
      or otherwise acquire, become interested in, deal in and with, invest in,
      hold, sell, mortgage, pledge or otherwise dispose of all forms of
      securities of such business concerns;

(e)   To acquire, and pay for in cash, with equity securities or debt securities
      issued by the corporation, with property of the corporation, whether real,
      personal, tangible or intangible, or otherwise, the good will, rights,
      assets and property, and to undertake or assume the whole or any part of
      the obligations or liabilities of, and to lend or extend credit to, any
      corporation, joint stock company, association, limited partnership,
      general partnership, firm, trust, joint venture enterprise, syndicate,
      consortium, combination or other entity or person;

(f)   To acquire, hold, use, sell, assign, lease, grant licenses in respect of,
      mortgage or otherwise dispose of letters patent of the United States or
      any foreign country, patent rights, licenses and privileges, inventions,
      improvements and processes, copyrights, trademarks and trade names;

(g)   To purchase, receive, take by gram, gift, devise, bequest or otherwise,
      lease, or otherwise acquire, own, hold, improve, employ, use and otherwise
      deal in and with real or personal property, or any interest therein,
      wherever situated, and to sell, convey, lease, exchange, transfer or
      otherwise dispose of, or mortgage or pledge, all or any of the property
      and assets, or any interest therein, of the corporation wherever situated;

(h)   To buy, utilize, lease, rent, import, export, manufacture, produce,
      design, prepare, assemble, fabricate, improve, develop, sell, lease,
      mortgage, pledge, hypothecate, distribute and otherwise deal in at
      wholesale, retail or otherwise, as a principal, agent or otherwise, all
      commodities, goods, wares, merchandise, machinery, tools, devices,
      apparatus, equipment and all other personal property, whether tangible or
      intangible, of every kind without limitation as to description, location
      or amount; and,

(i)   To engage in any lawful act or activity for which corporations may be
      organized under the General Corporation Law of the State of Delaware.

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      In addition to the powers and privileges conferred upon the corporation by
law, the corporation shall possess and may exercise all powers and privileges
which are necessary or convenient to the conduct, promotion or attainment of the
business, objects or purposes of the corporation.

      FOURTH. The total number of shares of stock which the corporation shall
have authority to issue is One Thousand (1,000) shares, of the par value of One
Hundred Dollars ($100.00) per share.

      FIFTH. The name and mailing address of the incorporator is as follows:



     Name                      Mailing Address
- -------------              -----------------------
                        
James Boyazis              1144 East Market Street
                           Akron, Ohio 44316-0001


      SIXTH. The corporation is to have perpetual existence.

      SEVENTH. The private property of the stockholders shall not be subject to
the payment of debts of the corporation to any extent whatsoever.

      EIGHTH. Elections of directors need not be by ballot unless the By-Laws of
the corporation shall so provide.

      NINTH. The By-Laws of the corporation may from time to time be adopted,
altered, amended, or repealed, or new By-Laws may be adopted, in either of the
following ways: (i) by the holders of a majority of the outstanding shares of
stock of the corporation entitled to vote, or (ii) by a majority of the full
board of directors. Any change so made by the stockholders may thereafter be
further changed by a majority of the directors unless the stockholders in
adopting such change shall otherwise provide.

      TENTH. The corporation may agree to the terms and conditions upon which
any director, officer, employee or agent accepts his office or position and in
its By-Laws or otherwise may agree to indemnify and protect any director,
officer, employee or agent to the extent permitted by the laws of Delaware. A
director of the corporation shall not be personally liable to the corporation or
its stockholders for monetary damages for breach of fiduciary duty as a director
except for liability (i) for any breach of the director's duty of loyalty to the
corporation or its stockholders, (ii) for acts or omissions not in good faith or
which involve intentional misconduct or a knowing violation of law, (iii) under
Section 174 of the Delaware Corporation Law, or (iv) for any transaction from
which the director derived any improper personal benefit.

      ELEVENTH. Whenever a compromise or arrangement is proposed between this

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corporation and its creditors or any class of them and/or between this
corporation and its stockholders or any class of them, any court of equitable
jurisdiction within the State of Delaware may, on the application in a summary
way of this corporation or of any creditor or stockholder thereof or on the
application of any receiver or receivers appointed for this corporation under
the provisions of Section 291 of Title 8 of the Delaware Code or on the
application of trustees in dissolution or of any receiver or receivers appointed
for this corporation under the provisions of Section 279 of Title 8 of the
Delaware Code order a meeting of the creditors or class of creditors, and/or of
the stockholders or class of stockholders of this corporation, as the case may
be, to be summoned in such manner as the said court directs. If a majority in
number representing three-fourths in value of the creditors or class of
creditors, and/or of the stockholders or class of stockholders of this
corporation, as the case may be, agree to any compromise or arrangement and to
any reorganization of this corporation as consequence of such compromise or
arrangement, the said compromise or arrangement and the said reorganization
shall, if sanctioned by the court to which the said application has been made,
be binding on all the creditors or class of creditors, and/or on all the
stockholders or class of stockholders, of this corporation, as the case may be,
and also on this corporation.

      TWELFTH. Meetings of stockholders may be held within or without the State
of Delaware, as the By-Laws may provide. The books of the corporation may be
kept (subject to any provision contained in the statutes of Delaware) outside
the State of Delaware at such place or places as may be designated from time to
time by the Board of Directors or in the By-Laws of the corporation.

      THIRTEENTH. The corporation reserves the right to amend, alter, change or
repeal any provision contained in this certificate of incorporation, in the
manner now or hereafter prescribed by statute, and all rights conferred upon
stockholders herein are granted subject to this reservation.

      FOURTEENTH. In furtherance and not in limitation of the powers conferred
by statute, the board of directors is expressly authorized: (1) to authorize and
cause to be executed mortgages and liens upon the real and persona] property of
the corporation; and (2) to set apart out of any of the funds of the corporation
available for dividends a reserve or reserves for any proper purpose and to
abolish any such reserve in the manner in which it was created.

      The undersigned, James Boyazis, bang the incorporator hereinbefore named,
for the purpose of forming a corporation pursuant to the General Corporation Law
of the State of Delaware, does hereby make this Certificate, hereby declaring
and certifying that this is his act and deed and the facts herein stated are
true, and, accordingly, has executed this Certificate this July 15, 1998.

                                        /s/ James Boyazis
                                        ------------------------------
                                        James Boyazis, Incorporator

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STATE OF OHIO       )
                    ) ss
COUNTY OF SUMMIT    )

      BE IT REMEMBERED that on this 15th day of July, 1998, personally became
before me, a Notary Public for the State of Ohio, James Boyazis, the person who
executed the foregoing Certificate of Incorporation, known to me personally to
be such, and acknowledged the said Certificate to be his act and deed and that
the facts stated therein are true.

      GIVEN under my hand and seal of office the day and year aforesaid.

                                                 /s/ Carolyn Sue Hayes
                                                 ---------------------
                                                 Notary Public
                                                 State of Ohio

                             CAROLYN SUE HAYES, Notary Public
                                  Reeldence-Summit County
(NOTARIAL SEAL)               State Wide Jurisdiction, Ohio
                            My Commission Expires: Oct. 7 1999

My commission expires: ____________________

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