<PAGE>   1
                                                                    EXHIBIT 3.2




                                    BY-LAWS



                                       OF



                                  DYNAMEX INC.
                            (a Delaware corporation)
<PAGE>   2
                                   ARTICLE I

                                    OFFICES

         Section 1.       Registered Office.  The registered office of the
Corporation shall be in the City of Wilmington, County of New Castle, State of
Delaware.

         Section 2.       Other Offices.  The Corporation may also have offices
at such other place or places, both within and without the State of Delaware,
as the Board of Directors may from time to time determine or the business of
the Corporation may require.

                                   ARTICLE II

                            MEETINGS OF STOCKHOLDERS

         Section 1.       Time and Place of Meetings.  All meetings of the
stockholders for the election of directors shall be held at such time and
place, either within or without the State of Delaware, as shall be designated
from time to time by the Board of Directors and stated in the notice of the
meeting.  Meetings of stockholders for any other purpose may be held at such
time and place, within or without the State of Delaware, as shall be stated in
the notice of the meeting or in a duly executed waiver of notice thereof.

         Section 2.       Annual Meetings.  Annual meetings of stockholders
shall be held on such date and at such time as shall be designated from time to
time by the Board of Directors and stated in the notice of the meeting, at
which meeting the stockholders shall elect by a plurality vote the number of
directors as provided for herein and shall transact such other business as may
properly be brought before the meeting. As used herein, "Restated Certificate
of Incorporation" shall include any Certificate of Designation of Preferred
Stock which may be filed from time to time by the Corporation.

         Section 3.       Notice of Annual Meetings.  Written notice of the
annual meeting, stating the place, date, and hour of the meeting, shall be
given to each stockholder of record entitled to vote at such meeting not less
than 10 or more than 60 days before the date of the meeting.

         Section 4.       Special Meetings.  Special meetings of the
stockholders for any purpose or purposes, unless otherwise prescribed by
statute or by the Restated Certificate of Incorporation, may be called at any
time exclusively by the order of the Board of Directors or by the Chairman of
the Board or the Chief Executive Officer pursuant to a resolution adopted by a
majority of the Board of Directors. Such request shall state the purpose or
purposes of the proposed special meeting.  Business transacted at any special
meeting of stockholders shall be limited to the purposes stated in the notice.

         Section 5.       Notice of Special Meetings.  Written notice of a
special meeting, stating the place, date, and hour of the meeting and the
purpose or purposes for which the meeting is called, shall be given to each
stockholder of record entitled to vote at such meeting not less than 10 or more
than 60 days before the date of the meeting.

         Section 6.       Quorum.  Except as otherwise provided by statute or
the Restated Certificate of Incorporation, the holders of stock having a
majority of the voting power of the stock entitled to be voted thereat, present
in person or represented by proxy, shall constitute





<PAGE>   3
a quorum for the transaction of business at all meetings of the stockholders.
If, however, such quorum shall not be present or represented at any meeting of
the stockholders, the stockholders entitled to vote thereat, present in person
or represented by proxy, shall have power to adjourn the meeting from time to
time without notice (other than announcement at the meeting at which the
adjournment is taken of the time and place of the adjourned meeting) until a
quorum shall be present or represented.  At such adjourned meeting at which a
quorum shall be present or represented, any business may be transacted which
might have been transacted at the meeting as originally notified.  If the
adjournment is for more than 30 days, or if after the adjournment a new record
date is fixed for the adjourned meeting, notice of the adjourned meeting shall
be given to each stockholder of record entitled to vote at the meeting.

         Section 7.       Organization.  At each meeting of the stockholders,
the Chairman of the Board or the President, determined as provided in Article
VIII of these By-Laws, or if those officers shall be absent therefrom, another
officer of the Corporation chosen as chairman present in person or by proxy and
entitled to vote thereat, or if all the officers of the Corporation shall be
absent therefrom, a stockholder holding of record shares of stock of the
Corporation so chosen, shall act as chairman of the meeting and preside
thereat. The Secretary, or if he shall be absent from such meeting or shall be
required pursuant to the provisions of this Section 7 to act as chairman of
such meeting, the person (who shall be an Assistant Secretary, if an Assistant
Secretary shall be present thereat) whom the chairman of such meeting shall
appoint, shall act as secretary of such meeting and keep the minutes thereof.

         Section 8.       Voting.  Except as otherwise provided in the Restated
Certificate of Incorporation, each stockholder shall, at each meeting of the
stockholders, be entitled to one vote in person or by proxy for each share of
stock of the Corporation held by him and registered in his name on the books of
the Corporation on the date fixed pursuant to the provisions of Section 5 of
Article X of these By-Laws as the record date for the determination of
stockholders who shall be entitled to notice of and to vote at such meeting.
Shares of its own stock belonging to the Corporation or to another corporation,
if a majority of the shares entitled to vote in the election of directors of
such other corporation is held directly or indirectly by the Corporation, shall
not be entitled to vote. Any vote by a stockholder may be given at any meeting
of the stockholders by the stockholder entitled thereto, in person or by one or
more agents authorized by written proxy signed by the person and filed with the
secretary of the Corporation. A proxy shall be deemed signed if the
stockholder's name is placed on the proxy (whether by manual signature,
typewriting, telegraphic transmission, telefacsimile or otherwise). No proxy
shall be voted or acted upon after three years from its date, unless said proxy
shall provide for a longer period.  Each proxy shall be revocable unless
expressly provided therein to be irrevocable and unless otherwise made
irrevocable by law.  At all meetings of the stockholders all matters, except
where other provision is made by law, the Restated Certificate of Incorporation
or these By-Laws, shall be decided by the vote of a majority of the votes cast
by the stockholders present in person or by proxy and entitled to vote thereat,
a quorum being present.  Unless demanded by a stockholder of the Corporation
present in person or by proxy at any meeting of the stockholders and entitled
to vote thereat, or so directed by the chairman of the meeting, the vote
thereat on any question other than the election or removal of directors need
not be by written ballot.  Upon a demand of any such





                                       2
<PAGE>   4
stockholder for a vote by written ballot on any question or at the direction of
such chairman that a vote by written ballot be taken on any question, such vote
shall be taken by written ballot.  On a vote by written ballot, each ballot
shall be signed by the stockholder voting, or by his proxy, if there be such
proxy, and shall state the number of shares voted.

         Section 9.       List of Stockholders.  It shall be the duty of the
Secretary or other officer of the Corporation who shall have charge of its
stock ledger, either directly or through another officer of the Corporation
designated by him or through a transfer agent appointed by the Board of
Directors, to prepare and make, at least 10 days before every meeting of the
stockholders, a complete list of the stockholders entitled to vote thereat,
arranged in alphabetical order, and showing the address of each stockholder and
the number of shares registered in the name of each stockholder. Such list
shall be open to the examination of any stockholder, for any purpose germane to
the meeting, during ordinary business hours, for a period of at least 10 days
before said meeting, either at a place within the city where said meeting is to
be held, which place shall be specified in the notice of said meeting, or, if
not so specified, at the place where said meeting is to be held.  The list
shall also be produced and kept at the time and place of said meeting during
the whole time thereof, and may be inspected by any stockholder of record who
shall be present thereat.  The stock ledger shall be the only evidence as to
who are the stockholders entitled to examine the stock ledger, such list or the
books of the Corporation, or to vote in person or by proxy at any meeting of
stockholders.

         Section 10.      Inspectors of Votes.  At each meeting of the
stockholders, the chairman of such meeting may appoint two Inspectors of Votes
to act thereat, unless the Board of Directors shall have theretofore made such
appointments.  Each Inspector of Votes so appointed shall first subscribe an
oath or affirmation faithfully to execute the duties of an Inspector of Votes
at such meeting with strict impartiality and according to the best of his
ability.  Such Inspectors of Votes, if any, shall take charge of the ballots,
if any, at such meeting and, after the balloting thereat on any question, shall
count the ballots cast thereon and shall make a report in writing to the
secretary of such meeting of the results thereof.  An Inspector of Votes need
not be a stockholder of the Corporation, and any officer of the Corporation may
be an Inspector of Votes on any question other than a vote for or against his
election to any position with the Corporation or on any other question in which
he may be directly interested.

         Section 11.      Actions Without a Meeting Prohibited.  Unless
otherwise provided in the Restated Certificate of Incorporation, no action that
is required or permitted to be taken by the stockholders of the Corporation at
any annual or special meeting of the stockholders of the Corporation may be
effected by written consent in lieu of a meeting of stockholders, unless the
action to be effected by written consent of the stockholders and the taking of
such action by written consent have expressly been approved in advance by the
Board of Directors.





                                       3
<PAGE>   5
                                  ARTICLE III

                               BOARD OF DIRECTORS

         Section 1.       Powers.  The business and affairs of the Corporation
shall be managed by its Board of Directors, which shall have and may exercise
all such powers of the Corporation and do all such lawful acts and things as
are not by statute, the Restated Certificate of Incorporation, or these By-Laws
directed or required to be exercised or done by the stockholders.

         Section 2.       Number, Qualification, and Term of Office.  The
number of directors which shall constitute the whole Board of Directors shall
not be less than one (1) nor more than fifteen (15).  Within the limits above
specified, the number of directors which shall constitute the whole Board of
Directors shall be determined from time to time exclusively by the Board of
Directors pursuant to a resolution adopted by at least a majority of the
directors. The directors shall be elected at the annual meeting of the
stockholders, except as provided in Sections 4 and 5 of this Article III, and
each director elected shall hold office until the annual meeting next after his
election and until his successor is duly elected and qualified, or until his
death or retirement or until he resigns or is removed in the manner hereinafter
provided.  Directors shall be elected by a plurality of the votes of the shares
present in person or represented by proxy and entitled to vote on the election
of directors at any annual or special meeting of stockholders.

         Section 3.       Resignations.  Any director may resign at any time by
giving written notice of his resignation to the Corporation.  Any such
resignation shall take effect at the time specified therein, or if the time
when it shall become effective shall not be specified therein, then it shall
take effect immediately upon its receipt by the Secretary.  Unless otherwise
specified therein, the acceptance of such resignation shall not be necessary to
make it effective.

         Section 4.       Removal of Directors.  Any director may be removed,
either with or without cause, at any time, by the affirmative vote of a
majority in voting interest of the stockholders of record of the Corporation
entitled to vote, given at an annual meeting or at a special meeting of the
stockholders called for that purpose.  The vacancy in the Board of Directors
caused by any such removal shall be filled by the stockholders at such meeting
or, if not so filled, by the Board of Directors as provided in Section 5 of
this Article III.

         Section 5.       Vacancies.  Subject to the rights of the holders of
any series of preferred stock and unless the Board of Directors otherwise
determines, newly created directorships resulting from any increase in the
authorized number of directors or any vacancies on the Board of Directors
resulting from death, resignation, retirement, disqualification, or removal
from office or other cause, shall be filled only by the affirmative vote of a
majority of the remaining directors then in office though less than a quorum,
and any director so chosen shall hold office for a term expiring at the next
annual meeting of stockholders and until such director's successor shall have
been elected and qualified, unless sooner displaced.  No





                                       4
<PAGE>   6
decrease in the number of directors constituting the Board of Directors shall
shorten the term of any incumbent director.

                                   ARTICLE IV

                       MEETINGS OF THE BOARD OF DIRECTORS

         Section 1.       Place of Meetings.  The Board of Directors of the
Corporation may hold meetings, both regular and special, either within or
without the State of Delaware.

         Section 2.       Annual Meetings.  The first meeting of each newly
elected Board of Directors shall be held immediately following the annual
meeting of stockholders, and no notice of such meeting to the newly elected
directors shall be necessary in order legally to constitute the meeting,
provided a quorum shall be present.  In the event such meeting is not held
immediately following the annual meeting of stockholders, the meeting may be
held at such time and place as shall be specified in a notice given as
hereinafter provided for special meetings of the Board of Directors, or as
shall be specified in a written waiver signed by all of the directors.

         Section 3.       Regular Meetings.  Regular meetings of the Board of
Directors may be held without notice at such time and at such place as shall
from time to time be determined by the Board of Directors.

         Section 4.       Special Meetings; Notice.  Special meetings of the
Board of Directors may be called by the Chairman of the Board, the President,
or the Secretary on 24 hours' notice to each director, either personally or by
telephone or by mail, telegraph, telex, cable, wireless, or other form of
recorded communication; special meetings shall be called by the Chairman of the
Board, the President, or the Secretary in like manner and on like notice on the
written request of two directors.  Notice of any such meeting need not be given
to any director, however, if waived by him in writing or by telegraph, telex,
cable, wireless, or other form of recorded communication, or if he shall be
present at such meeting.

         Section 5.       Quorum and Manner of Acting.  At all meetings of the
Board of Directors, a majority of the directors at the time in office shall
constitute a quorum for the transaction of business, and the act of a majority
of the directors present at any meeting at which a quorum is present shall be
the act of the Board of Directors, except as may be otherwise specifically
provided by statute or by the Restated Certificate of Incorporation.  If a
quorum shall not be present at any meeting of the Board of Directors, the
directors present thereat may adjourn the meeting from time to time, without
notice other than announcement at the meeting, until a quorum shall be present.

         Section 6.       Remuneration.  The Board of Directors may at any time
and from time to time by resolution provide that a specified sum shall be paid
to any director of the Corporation, either as his annual remuneration as such
director or member of any committee of the Board of Directors or as
remuneration for his attendance at each meeting of the Board of Directors or
any such committee.  The Board of Directors may also likewise provide that the





                                       5
<PAGE>   7
Corporation shall reimburse each director for any expenses paid by him on
account of his attendance at any meeting.  Nothing in this Section 6 shall be
construed to preclude any director from serving the Corporation in any other
capacity and receiving remuneration therefor.

                                   ARTICLE V

                            COMMITTEES OF DIRECTORS

         Section 1.       Executive Committee; How Constituted and Powers. The
Board of Directors may in its discretion, by resolution passed by a majority of
the whole Board of Directors, designate an Executive Committee consisting of
one or more of the directors of the Corporation.  Subject to the provisions of
Section 141 of the General Corporation Law of the State of Delaware, the
Restated Certificate of Incorporation, and these By-Laws, the Executive
Committee shall have and may exercise, when the Board of Directors is not in
session, all the powers and authority of the Board of Directors in the
management of the business and affairs of the Corporation, and shall have the
power to authorize the seal of the Corporation to be affixed to all papers
which may require it; but the Executive Committee shall not have the power to
fill vacancies in the Board of Directors, the Executive Committee, or any other
committee of directors or to elect or approve officers of the Corporation.
Except as otherwise provided herein or in the Corporation's Restated
Certificate of Incorporation, the Executive Committee shall have the power and
authority to authorize the issuance of common stock and grant and authorize
options and other rights with respect to such issuance. The Board of Directors
shall have the power at any time, by resolution passed by a majority of the
whole Board of Directors, to change the membership of the Executive Committee,
to fill all vacancies in it, or to dissolve it, either with or without cause.

         Section 2.       Organization.  The Chairman of the Executive
Committee, to be selected by the Board of Directors, shall act as chairman at
all meetings of the Executive Committee and the Secretary shall act as
secretary thereof.  In case of the absence from any meeting of the Executive
Committee of the Chairman of the Executive Committee or the Secretary, the
Executive Committee may appoint a chairman or secretary, as the case may be, of
the meeting.

         Section 3.       Meetings.  Regular meetings of the Executive
Committee, of which no notice shall be necessary, may be held on such days and
at such places, within or without the State of Delaware, as shall be fixed by
resolution adopted by a majority of the Executive Committee and communicated in
writing to all its members.  Special meetings of the Executive Committee shall
be held whenever called by the Chairman of the Executive Committee or a
majority of the members of the Executive Committee then in office.  Notice of
each special meeting of the Executive Committee shall be given by mail,
telegraph, telex, cable, wireless, or other form of recorded communication or
be delivered personally or by telephone to each member of the Executive
Committee not later than the day before the day on which such meeting is to be
held.  Notice of any such meeting need not be given to any member of the
Executive Committee, however, if waived by him in writing or by telegraph,
telex, cable, wireless, or other form of recorded communication, or if he shall
be present at such meeting;





                                       6
<PAGE>   8
and any meeting of the Executive Committee shall be a legal meeting without any
notice thereof having been given, if all the members of the Executive Committee
shall be present thereat.  Subject to the provisions of this Article V, the
Executive Committee, by resolution adopted by a majority of the whole Executive
Committee, shall fix its own rules of procedure.

         Section 4.       Quorum and Manner of Acting.  A majority of the
Executive Committee shall constitute a quorum for the transaction of business,
and the act of a majority of those present at a meeting thereof at which a
quorum is present shall be the act of the Executive Committee.

         Section 5.       Other Committees.  The Board of Directors may, by
resolution or resolutions passed by a majority of the whole Board of Directors,
designate one or more other committees consisting of one or more directors of
the Corporation, which, to the extent provided in said resolution or
resolutions, shall have and may exercise, subject to the provisions of Section
141 of the General Corporation Law of the State of Delaware, the Restated
Certificate of Incorporation, and these By-Laws, the powers and authority of
the Board of Directors in the management of the business and affairs of the
Corporation, and shall have the power to authorize the seal of the Corporation
to be affixed to all papers which may require it; but no such committee shall
have the power to fill vacancies in the Board of Directors, the Executive
Committee, or any other committee or in their respective membership, to appoint
or remove officers of the Corporation, or to authorize the issuance of shares
of the capital stock of the Corporation, except that such a committee may, to
the extent provided in said resolutions, grant and authorize options and other
rights with respect to the common stock of the Corporation pursuant to and in
accordance with any plan approved by the Board of Directors.  Such committee or
committees shall have such name or names as may be determined from time to time
by resolution adopted by the Board of Directors.  A majority of all the members
of any such committee may determine its action and fix the time and place of
its meetings and specify what notice thereof, if any, shall be given, unless
the Board of Directors shall otherwise provide.  The Board of Directors shall
have power to change the members of any such committee at any time to fill
vacancies, and to discharge any such committee, either with or without cause,
at any time.

         Section 6.       Alternate Members of Committees.  The Board of
Directors may designate one or more directors as alternate members of the
Executive Committee or any other committee, who may replace any absent or
disqualified member at any meeting of the committee, or if none be so
appointed, the member or members thereof present at any meeting and not
disqualified from voting, whether or not he or they constitute a quorum, may
unanimously appoint another member of the Board of Directors to act at the
meeting in the place of any such absent or disqualified member.

         Section 7.       Minutes of Committees.  Each committee shall keep
regular minutes of its meetings and proceedings and report the same to the
Board of Directors at the next meeting thereof.





                                       7
<PAGE>   9
                                   ARTICLE VI

                                    GENERAL

         Section 1.       Actions Without a Meeting.  Unless otherwise
restricted by the Restated Certificate of Incorporation or these By-Laws, any
action required or permitted to be taken at any meeting of the Board of
Directors or of any committee thereof may be taken without a meeting, if all
members of the Board of Directors or committee, as the case may be, consent
thereto in writing and the writing or writings are filed with the minutes of
proceedings of the Board of Directors or the committee.

         Section 2.       Presence at Meetings by Means of Communications
Equipment.  Members of the Board of Directors, or of any committee designated
by the Board of Directors, may participate in a meeting of the Board of
Directors or such committee by means of conference telephone or similar
communications equipment by means of which all persons participating in the
meeting can hear each other, and participation in a meeting conducted pursuant
to this Section 2 shall constitute presence in person at such meeting.

                                  ARTICLE VII

                                    NOTICES

         Section 1.       Type of Notice.  Whenever, under the provisions of
any applicable statute, the Restated Certificate of Incorporation, or these
By-Laws, notice is required to be given to any director or stockholder, it
shall not be construed to mean personal notice, but such notice may be given in
writing, in person or by mail, addressed to such director or stockholder, at
his address as it appears on the records of the Corporation, with postage
thereon prepaid, and such notice shall be deemed to be given at the time when
the same shall be deposited in the United States mail.  Notice to directors may
also be given in any manner permitted by Article III hereof and shall be deemed
to be given at the time when first transmitted by the method of communication
so permitted.

         Section 2.       Waiver of Notice.  Whenever any notice is required to
be given under the provisions of any applicable statute, the Restated
Certificate of Incorporation, or these By-Laws, a waiver thereof in writing,
signed by the person or persons entitled to said notice, whether before or
after the time stated therein, shall be deemed equivalent thereto, and
transmission of a waiver of notice by a director or stockholder by mail,
telegraph, telex, cable, wireless, or other form of recorded communication may
constitute such a waiver.

                                  ARTICLE VIII

                                    OFFICERS

         Section 1.       Elected and Appointed Officers.  The elected officers
of the Corporation shall be a President and a Secretary, and, if the Board of
Directors so elects, a Chairman of the Board (who shall be a director), one or
more Vice Presidents, with or without such





                                       8
<PAGE>   10
descriptive titles as the Board of Directors shall deem appropriate, a
Controller and a Treasurer.  The Board of Directors or the Executive Committee
of the Board of Directors by resolution also may appoint one or more Assistant
Vice Presidents, Assistant Treasurers, Assistant Secretaries, Assistant
Controllers, and such other officers and agents as from time to time may appear
to be necessary or advisable in the conduct of the affairs of the Corporation.

         Section 2.       Time of Election or Appointment.  The Board of
Directors at its annual meeting shall elect or appoint, as the case may be, the
officers to fill the positions designated in or pursuant to Section 1 of this
Article VIII.  Officers of the Corporation may also be elected or appointed, as
the case may be, at any other time.

         Section 3.       Salaries of Elected Officers.  The salaries of all
elected officers of the Corporation shall be fixed by the Board of Directors.

         Section 4.       Term.  Each officer of the Corporation shall hold his
office until his successor is duly elected or appointed and qualified or until
his earlier resignation or removal.  Any officer may resign at any time upon
written notice to the Corporation. Any officer elected or appointed by the
Board of Directors or the Executive Committee may be removed at any time by the
affirmative vote of a majority of the whole Board of Directors.  Any vacancy
occurring in any office of the Corporation by death, resignation, removal, or
otherwise may be filled by the Board of Directors or the appropriate committee
thereof.

         Section 5.       Duties of the Chairman of the Board.  The Chairman of
the Board, if one be elected, shall preside when present at all meetings of the
Board of Directors and, with the approval of the President, may preside at
meetings of the stockholders.  He shall advise and counsel the President and
other officers of the Corporation, and shall exercise such powers and perform
such duties as shall be assigned to or required of him from time to time by the
Board of Directors.

         Section 6.       Duties of the President.  The President shall be the
chief executive officer of the Corporation and, subject to the provisions of
these By-Laws, shall have general supervision of the affairs of the Corporation
and shall have general and active control of all its business.  He shall
preside, when present, at all meetings of stockholders, except when the
Chairman of the Board presides with the approval of the President and as may
otherwise be provided by statute, and, in the absence of any other person
designated thereto by these By-Laws, at all meetings of the Board of Directors.
He shall see that all orders and resolutions of the Board of Directors and the
stockholders are carried into effect.  He shall have general authority to
execute bonds, deeds, and contracts in the name of the Corporation and affix
the corporate seal thereto; to sign stock certificates; to cause the employment
or appointment of such employees and agents of the Corporation as the proper
conduct of operations may require, and to fix their compensation, subject to
the provisions of these By-Laws; to remove or suspend any employee or agent who
shall have been employed or appointed under his authority or under authority of
an officer subordinate to him; to suspend for cause, pending final action by
the authority which shall have elected or appointed him, any officer
subordinate to the President; and, in general, to exercise all the powers and
authority usually appertaining to the chief executive officer of a corporation,
except as otherwise provided in these By-Laws.





                                       9
<PAGE>   11
         Section 7.       Duties of Vice Presidents.  In the absence of the
President or in the event of his inability or refusal to act, the Vice
President (or in the event there be more than one Vice President, the Vice
Presidents in the order designated, or in the absence of any designation, then
in the order of their election) shall perform the duties of the President and,
when so acting, shall have all the powers of and be subject to all the
restrictions upon the President.  The Vice Presidents shall perform such other
duties and have such other powers as the Board of Directors or the President
may from time to time prescribe.

         Section 8.       Duties of Assistant Vice Presidents.  In the absence
of a Vice President or in the event of his inability or refusal to act, the
Assistant Vice President (or in the event there shall be more than one, the
Assistant Vice Presidents in the order designated by the Board of Directors, or
in the absence of any designation, then in the order of their appointment)
shall perform the duties and exercise the powers of that Vice President, and
shall perform such other duties and have such other powers as the Board of
Directors, the President, or the Vice President under whose supervision he is
appointed may from time to time prescribe.

         Section 9.       Duties of the Secretary.  The Secretary shall attend
all meetings of the Board of Directors and all meetings of the stockholders and
record all the proceedings of the meetings of the Corporation and of the Board
of Directors in a book to be kept for that purpose and shall perform like
duties for the Executive Committee or other standing committees when required.
He shall give, or cause to be given, notice of all meetings of the stockholders
and special meetings of the Board of Directors, and shall perform such other
duties as may be prescribed by the Board of Directors or the President, under
whose supervision he shall be.  He shall have custody of the corporate seal of
the Corporation, and he, or an Assistant Secretary, shall have authority to
affix the same to any instrument requiring it, and when so affixed, it may be
attested by his signature or by the signature of such Assistant Secretary.  The
Board of Directors may give general authority to any other officer to affix the
seal of the Corporation and to attest the affixing by his signature.  The
Secretary shall keep and account for all books, documents, papers, and records
of the Corporation, except those for which some other officer or agent is
properly accountable.  He shall have authority to sign stock certificates and
shall generally perform all the duties usually appertaining to the office of
the secretary of a corporation.

         Section 10.      Duties of Assistant Secretaries.  In the absence of
the Secretary or in the event of his inability or refusal to act, the Assistant
Secretary (or, if there shall be more than one, the Assistant Secretaries in
the order designated by the Board of Directors, or in the absence of any
designation, then in the order of their appointment) shall perform the duties
and exercise the powers of the Secretary and shall perform such other duties
and have such other powers as the Board of Directors, the President, or the
Secretary may from time to time prescribe.

         Section 11.      Duties of the Treasurer.  The Treasurer shall have
the custody of the corporate funds and securities and shall keep full and
accurate accounts of receipts and disbursements in books belonging to the
Corporation and shall deposit all moneys and other valuable effects in the name
and to the credit of the Corporation in such depositories as may





                                       10
<PAGE>   12
be designated by the Board of Directors.  He shall disburse the funds of the
Corporation as may be ordered by the Board of Directors, taking proper vouchers
for such disbursements, and shall render to the President and the Board of
Directors, at its regular meetings or when the Board of Directors so requires,
an account of all his transactions as Treasurer and of the financial condition
of the Corporation.  If required by the Board of Directors, he shall give the
Corporation a bond (which shall be renewed every six years) in such sum and
with such surety or sureties as shall be satisfactory to the Board of Directors
for the faithful performance of the duties of his office and for the
restoration to the Corporation, in case of his death, resignation, retirement,
or removal from office, of all books, papers, vouchers, money, and other
property of whatever kind in his possession or under his control belonging to
the Corporation. The Treasurer shall be under the supervision of the Vice
President in charge of finance, if one is so designated, and he shall perform
such other duties as may be prescribed by the Board of Directors, the
President, or any such Vice President in charge of finance.

         Section 12.      Duties of Assistant Treasurers.  The Assistant
Treasurer or Assistant Treasurers shall assist the Treasurer, and in the
absence of the Treasurer or in the event of his inability or refusal to act,
the Assistant Treasurer (or in the event there shall be more than one, the
Assistant Treasurers in the order designated by the Board of Directors, or in
the absence of any designation, then in the order of their appointment) shall
perform the duties and exercise the powers of the Treasurer and shall perform
such other duties and have such other powers as the Board of Directors, the
President, or the Treasurer may from time to time prescribe.

         Section 13.      Duties of the Controller.  The Controller, if one is
appointed, shall have supervision of the accounting practices of the
Corporation and shall prescribe the duties and powers of any other accounting
personnel of the Corporation.  He shall cause to be maintained an adequate
system of financial control through a program of budgets and interpretive
reports.  He shall initiate and enforce measures and procedures whereby the
business of the Corporation shall be conducted with the maximum efficiency and
economy.  If required, he shall prepare a monthly report covering the operating
results of the Corporation.  The Controller shall be under the supervision of
the Vice President in charge of finance, if one is so designated, and he shall
perform such other duties as may be prescribed by the Board of Directors, the
President, or any such Vice President in charge of finance.

         Section 14.      Duties of Assistant Controllers.  The Assistant
Controller or Assistant Controllers shall assist the Controller, and in the
absence of the Controller or in the event of his inability or refusal to act,
the Assistant Controller (or, if there shall be more than one, the Assistant
Controllers in the order designated by the Board of Directors, or in the
absence of any designation, then in the order of their appointment) shall
perform the duties and exercise the powers of the Controller and perform such
other duties and have such other powers as the Board of Directors, the
President, or the Controller may from time to time prescribe.





                                       11
<PAGE>   13
                                   ARTICLE IX

                                INDEMNIFICATION

         Section 1.       Actions Other Than by or in the Right of the
Corporation. The Corporation shall indemnify any person who was or is a party
or is threatened to be made a party to any threatened, pending, or contemplated
action, suit, or proceeding, whether civil, criminal, administrative, or
investigative (other than an action by or in the right of the Corporation), by
reason of the fact that he is or was a director or officer of the Corporation,
or is or was serving at the request of the Corporation as a director, officer,
trustee, employee, or agent of another corporation, partnership, joint venture,
trust, or other enterprise (all of such persons being hereafter referred to in
this Article as a "Corporate Functionary"), against expenses (including
attorneys' fees), judgments, fines, and amounts paid in settlement actually and
reasonably incurred by him in connection with such action, suit, or proceeding,
if he acted in good faith and in a manner he reasonably believed to be in or
not opposed to the best interests of the Corporation and, with respect to any
criminal action or proceeding, had no reasonable cause to believe his conduct
was unlawful.  The termination of any action, suit, or proceeding by judgment,
order, settlement, or conviction, or upon a plea of nolo contendere or its
equivalent, shall not, of itself, create a presumption that the person did not
act in good faith and in a manner which he reasonably believed to be in or not
opposed to the best interests of the Corporation or, with respect to any
criminal action or proceeding, that he had reasonable cause to believe that his
conduct was unlawful.

         Section 2.       Actions by or in the Right of the Corporation.  The
Corporation shall indemnify any person who was or is a party or is threatened
to be made a party to any threatened, pending, or contemplated action or suit
by or in the right of the Corporation to procure a judgment in its favor by
reason of the fact that he is or was a Corporate Functionary against expenses
(including attorneys' fees) actually and reasonably incurred by him in
connection with the defense or settlement of such action or suit, if he acted
in good faith and in a manner he reasonably believed to be in or not opposed to
the best interests of the Corporation, except that no indemnification shall be
made in respect of any claim, issue, or matter as to which such person shall
have been adjudged to be liable to the Corporation, unless and only to the
extent that the Court of Chancery or the court in which such action or suit was
brought shall determine upon application that, despite the adjudication of
liability but in view of all the circumstances of the case, such person is
fairly and reasonably entitled to indemnity for such expenses which the Court
of Chancery or such other court shall deem proper.

         Section 3.       Determination of Right to Indemnification.  Any
indemnification under Sections 1 or 2 of this Article IX (unless ordered by a
court) shall be made by the Corporation only as authorized in the specific case
upon a determination that indemnification of the Corporate Functionary is
proper in the circumstances because he has met the applicable standard of
conduct set forth in Sections 1 or 2 of this Article IX.  Such determination
shall be made (i) by the Board of Directors by a majority vote of a quorum
consisting of directors who were not parties to such action, suit, or
proceeding, or (ii) if such a quorum is not





                                       12
<PAGE>   14
obtainable, or, even if obtainable if a quorum of disinterested directors so
directs, by independent legal counsel in a written opinion, or (iii) by the
stockholders.

         Section 4.       Right to Indemnification.  Notwithstanding the other
provisions of this Article IX, to the extent that a Corporate Functionary has
been successful on the merits or otherwise in defense of any action, suit, or
proceeding referred to in Sections 1 or 2 of this Article IX (including the
dismissal of a proceeding without prejudice or the settlement of a proceeding
without admission of liability), or in defense of any claim, issue, or matter
therein, he shall be indemnified against expenses (including attorneys' fees)
actually and reasonably incurred by him in connection therewith.

         Section 5.       Prepaid Expenses.  Expenses incurred in defending a
civil or criminal action, suit, or proceeding shall be paid by the Corporation
in advance of the final disposition of such action, suit, or proceeding, upon
receipt of an undertaking by or on behalf of the Corporate Functionary to repay
such amount if it shall ultimately be determined he is not entitled to be
indemnified by the Corporation as authorized in this Article IX.

         Section 6.       Right to Indemnification upon Application; Procedure
upon Application.  Any indemnification under Sections 2, 3 and 4, or any
advance under Section 5, of this Article IX shall be made promptly upon, and in
any event within 60 days after, the written request of the Corporate
Functionary, unless with respect to applications under Sections 2, 3 or 5 of
this Article IX, a determination is reasonably and promptly made by the Board
of Directors by majority vote of a quorum consisting of disinterested directors
that such Corporate Functionary acted in a manner set forth in such Sections as
to justify the Corporation in not indemnifying or making an advance of expenses
to the Corporate Functionary.  If no quorum of disinterested directors is
obtainable, the Board of Directors shall promptly direct that independent legal
counsel shall decide whether the Corporate Functionary acted in a manner set
forth in such Sections as to justify the Corporation's not indemnifying or
making an advance of expenses to the Corporate Functionary.  The right to
indemnification or advance of expenses granted by this Article IX shall be
enforceable by the Corporate Functionary in any court of competent jurisdiction
if the Board of Directors or independent legal counsel denies his claim, in
whole or in part, or if no disposition of such claim is made within 60 days.
The expenses of the Corporate Functionary incurred in connection with
successfully establishing his right to indemnification, in whole or in part, in
any such proceeding shall also be indemnified by the Corporation.

         Section 7.       Other Rights and Remedies.  The indemnification and
advancement of expenses or provided by or granted pursuant to this Article IX
shall not be deemed exclusive of any other rights to which any person seeking
indemnification and advancement of expenses or may be entitled under any
by-law, agreement, vote of stockholders or disinterested directors, or
otherwise, both as to action in his official capacity and as to action in
another capacity while holding such office, and shall, unless otherwise
provided when authorized or ratified, continue as to a person who has ceased to
be a Corporate Functionary and shall inure to the benefit of the heirs,
executors, and administrators of such a person.  Any repeal or modification of
these by-laws or relevant provisions of the Delaware General Corporation Law





                                       13
<PAGE>   15
and other applicable law, if any, shall not affect any then existing rights of
a Corporate Functionary to indemnification or advancement of expenses.

         Section 8.       Insurance.  Upon resolution passed by the Board of
Directors, the Corporation may purchase and maintain insurance on behalf of any
person who is or was a director, officer, employee, or agent of the
Corporation, or is or was serving at the request of the Corporation as a
director, officer, employee, or agent of another corporation, partnership,
joint venture, trust, or other enterprise against any liability asserted
against him and incurred by him in any such capacity, or arising out of his
status as such, whether or not the Corporation would have the power to
indemnify him against such liability under the provisions of this Article IX.

         Section 9.       Mergers.  For purposes of this Article IX, references
to "the Corporation" shall include, in addition to the resulting or surviving
corporation, constituent corporations (including any constituent of a
constituent) absorbed in a consolidation or merger which, if its separate
existence had continued, would have had power and authority to indemnify its
directors and officers so that any person who is or was a director or officer
of such constituent corporation or is or was serving at the request of such
constituent corporation as a director, officer, employee, or agent of another
corporation, partnership, joint venture, trust, or other enterprise shall stand
in the same position under the provisions of this Article IX with respect to
the resulting or surviving corporation as he would have with respect to such
constituent corporation if its separate existence had continued.

         Section 10.  Savings Provision.  If this Article IX or any portion
hereof shall be invalidated on any ground by a court of competent jurisdiction,
the Corporation shall nevertheless indemnify each Corporate Functionary as to
expenses (including attorneys' fees), judgments, fines, and amounts paid in
settlement with respect to any action, suit, proceeding, or investigation,
whether civil, criminal, or administrative, including a grand jury proceeding
or action or suit brought by or in the right of the Corporation, to the full
extent permitted by any applicable portion of this Article IX that shall not
have been invalidated.

                                   ARTICLE X

                        CERTIFICATES REPRESENTING STOCK

         Section 1.       Right to Certificate.  Every holder of stock in the
Corporation shall be entitled to have a certificate, signed by, or in the name
of the Corporation by, the Chairman of the Board, the President, or a Vice
President and by the Secretary or an Assistant Secretary of the Corporation,
certifying the number of shares owned by him in the Corporation.  If the
Corporation shall be authorized to issue more than one class of stock or more
than one series of any class, the powers, designations, preferences, and
relative, participating, optional, or other special rights of each class of
stock or series thereof and the qualifications, limitations, or restrictions of
such preferences or rights shall be set forth in full or summarized on the face
or back of the certificate which the Corporation shall issue to represent such
class or series of stock; provided, that, except as otherwise provided in
Section 202 of the General Corporation Law of the State of Delaware, in lieu of
the foregoing requirements, there may be





                                       14
<PAGE>   16
set forth on the face or back of the certificate which the Corporation shall
issue to represent such class or series of stock a statement that the
Corporation will furnish without charge to each stockholder who so requests the
powers, designations, preferences, and relative, participating, optional, or
other special rights of each class of stock or series thereof and the
qualifications, limitations, or restrictions of such preferences or rights.

         Section 2.       Facsimile Signatures.  Any of or all the signatures
on the certificate may be facsimile.  In case any officer, transfer agent, or
registrar who has signed or whose facsimile signature has been placed upon a
certificate shall have ceased to be such officer, transfer agent, or registrar
before such certificate is issued, it may be issued by the Corporation with the
same effect as if he were such officer, transfer agent, or registrar at the
date of issue.

         Section 3.       New Certificates.  The officers of the Corporation
may authorize the Corporation's transfer agent to direct a new certificate or
certificates to be issued in place of any certificate or certificates
theretofore issued by the Corporation and alleged to have been lost, stolen, or
destroyed, upon the making of an affidavit of that fact by the person claiming
the certificate of stock to be lost, stolen, or destroyed.  When authorizing
such issue of a new certificate or certificates, an officer of the Corporation
may, in his discretion and as a condition precedent to the issuance thereof,
require the owner of such lost, stolen, or destroyed certificate or
certificates, or his legal representative, to advertise the same in such manner
as it shall require or to give the Corporation a bond in such sum as it may
direct as indemnity against any claim that may be made against the Corporation
with respect to the certificate alleged to have been lost, stolen, or destroyed
or the issuance of such new certificate.

         Section 4.       Transfers.  Upon surrender to the Corporation or the
transfer agent of the Corporation of a certificate for shares duly endorsed or
accompanied by proper evidence of succession, assignation, or authority to
transfer, it shall be the duty of the Corporation, subject to any proper
restrictions on transfer, to issue a new certificate to the person entitled
thereto, cancel the old certificate, and record the transaction upon its books.

         Section 5.       Record Date.  The Board of Directors may fix in
advance a date, not preceding the date on which the resolution fixing the
record date is adopted, and

         (i)     not more than 60 days nor less than 10 days preceding the date
                 of any meeting of stockholders, as a record date for the
                 determination of the stockholders entitled to notice of, and
                 to vote at, any such meeting and any adjournment thereof,

         (ii)    not more than 10 days after the date on which the resolution
                 fixing the record date is adopted, as a record date in
                 connection with obtaining a consent of the stockholders in
                 writing to corporate action without a meeting, or

         (iii)   not more than 60 days before the date for payment of any
                 dividend or distribution, or the date for the allotment of
                 rights, or the date when any





                                       15
<PAGE>   17
                 change, or conversion or exchange of capital stock shall go
                 into effect, or the date on which any other lawful action
                 shall be taken, as the record date for determining the
                 stockholders entitled to receive payment of any such dividend
                 or distribution, or to receive any such allotment of rights,
                 or to exercise the rights in respect of any such change,
                 conversion or exchange of capital stock or other lawful action
                 of the corporation,

and in such case such stockholders and only such stockholders as shall be
stockholders of record on the date so fixed shall be entitled to such notice
of, and to vote at, any such meeting and any adjournment thereof (provided,
however, that the Board of Directors may fix a new record date for an adjourned
meeting), or to give such consent, or to receive payment of such dividend or
distribution, or to receive such allotment of rights, or to exercise such
rights, as the case may be, notwithstanding any transfer of any stock on the
books of the corporation after any such record date fixed as aforesaid.

         Section 6.       Registered Stockholders.  The Corporation shall be
entitled to recognize the exclusive right of a person registered on its books
as the owner of shares to receive dividends, and to vote as such owner, and to
hold liable for calls and assessments a person registered on its books as the
owner of shares, and shall not be bound to recognize any equitable or other
claim to or interest in such share or shares on the part of any other person,
whether or not provided by the laws of the State of Delaware.

                                   ARTICLE XI

                               GENERAL PROVISIONS

         Section 1.       Dividends.  Dividends upon the capital stock of the
Corporation, if any, subject to the provisions of the Restated Certificate of
Incorporation, may be declared by the Board of Directors (but not any committee
thereof) at any regular meeting, pursuant to law.  Dividends may be paid in
cash, in property, or in shares of the capital stock, subject to the provisions
of the Restated Certificate of Incorporation.

         Section 2.       Reserves.  Before payment of any dividend, there may
be set aside out of any funds of the Corporation available for dividends such
sum or sums as the Board of Directors from time to time, in their absolute
discretion, thinks proper as a reserve or reserves to meet contingencies, or
for equalizing dividends, or for repairing or maintaining any property of the
Corporation, or for such other purpose as the Board of Directors shall think
conducive to the interest of the Corporation, and the Board of Directors may
modify or abolish any such reserve in the manner in which it was created.

         Section 3.       Checks.  All checks or demands for money and
promissory notes of the Corporation shall be signed by such officer or officers
or such other person or persons as the Board of Directors may from time to time
prescribe.

         Section 4.       Fiscal Year.  The fiscal year of the Corporation
shall be determined by the Board of Directors.





                                       16
<PAGE>   18
         Section 5.       Corporate Seal.  The corporate seal shall have
inscribed thereon the name of the Corporation.  The seal may be used by causing
it or a facsimile thereof to be impressed, affixed, reproduced, or otherwise.

                                  ARTICLE XII

                                   AMENDMENTS

         These By-Laws may be altered, amended, or repealed or new By-Laws may
be adopted by a majority of the members of the Board of Directors.





                                       17
<PAGE>   19
                                 CERTIFICATION



         I, Assistant Secretary of the Corporation, hereby certify that the
foregoing is a true, accurate and complete copy of the Bylaws of Dynamex Inc.
adopted by its Board of Directors as of October ____, 1997.



                                          /s/ Robert P. Capps
                                        ------------------------------------
                                        Robert P. Capps, Assistant Secretary





                                       18