<PAGE>

                                                                     EXHIBIT 3.2


                                 SIXTH RESTATED
                                    BYLAWS OF
                       STEWART & STEVENSON SERVICES, INC.
                            EFFECTIVE APRIL 11, 2000

                                    ARTICLE I

                                     OFFICES

      SECTION 1.1. OFFICES. The principal business office of the Corporation
shall be at Houston, Texas or at such other location within the State of Texas
as the Board of Directors may, from time to time, establish by resolution. The
Corporation may have such other business offices within or without the State of
Texas as the Board of Directors may from time to time establish or the business
of the Corporation may require.

                                   ARTICLE II

                                  CAPITAL STOCK

      SECTION 2.1. CERTIFICATES REPRESENTING SHARES. Certificates representing
shares of stock of the Corporation shall be consecutively numbered and in such
form or forms as comply with the requirements of law and the Restated Articles
of Incorporation and as the Board of Directors shall approve. Such certificates
shall be signed by the President or a Vice President, and the Secretary or an
Assistant Secretary of the Corporation, and may be sealed with the seal of the
Corporation or a facsimile thereof. The signatures of the President or Vice
President and the Secretary or Assistant Secretary may be facsimiles, engraved
or printed, if the certificate is countersigned by a transfer agent, or
registered by a registrar, other than the Corporation itself or an employee of
the Corporation. In case any officer or officers who have signed or whose
facsimile signature or signatures have been placed upon such certificate shall
have ceased to be such officer or officers before such certificate is issued, it
may be adopted and issued by the Corporation with the same effect as if he or
they had not ceased to be such officer or officers as of the date of its
issuance, and the issuance and delivery thereof by the Corporation shall
constitute adoption thereof by the Corporation.

      SECTION 2.2. STOCK CERTIFICATE REGISTER AND SHAREHOLDERS OF RECORD. The
Secretary of the Corporation shall keep at the registered office of the
Corporation, or cause a duly appointed transfer agent or registrar to keep at
its principal office, a share register showing the names of the shareholders and
their addresses, the number of shares held by each, the number and date of issue
of all certificates representing shares of the Corporation, the number and date
of cancellation of every certificate surrendered for cancellation and whether
such certificates originated from original issue or transfer. Such information
may be kept in any medium capable of reproducing the information in clearly
legible form and shall be the official list of shareholders of record of the
Corporation for all purposes. The Corporation shall be entitled to treat the
holder of


<PAGE>

record of any shares of the Corporation as the owner thereof for all purposes,
and shall not be bound to recognize any equitable or other claim to, or interest
in, such shares or any rights deriving from such shares on the part of any other
person, including (but without limitation) a purchaser, assignee, or transferee,
unless and until such other person becomes the holder of record of such shares,
whether or not the Corporation shall have either actual or constructive notice
of the interest of such other person.

      SECTION 2.3. TRANSFER OF STOCK. The shares represented by any share
certificates of the Corporation are transferable only on the stock certificate
register of the Corporation by the holder of record thereof in person or by a
duly authorized attorney or legal representative upon surrender of the
certificate for such shares properly endorsed or assigned.

      SECTION 2.4. TRANSFER AGENT AND REGISTRAR. The Board of Directors may
appoint one or more transfer agents or registrars of the shares, or both, and
may require all share certificates to bear the signature of a transfer agent or
registrar or both.

      SECTION 2.5. LOST, STOLEN OR DESTROYED CERTIFICATES. The Corporation may
issue a new certificate for shares of stock in the place of any certificate
theretofore issued and alleged to have been lost, stolen or destroyed, but the
Board of Directors may require the owner of such lost, stolen or destroyed
certificate, or his legal representative, to furnish an affidavit as to such
loss, theft, or destruction and to give a bond in such form and substance, and
with such surety or sureties, with fixed or open penalty, as it may direct, to
indemnify the Corporation, and the transfer agents and registrars, if any,
against any claim that may be made on account of the alleged loss, theft or
destruction of such certificate. Any such new certificate shall be plainly
marked "Duplicate" on its face.

                                   ARTICLE III

                                THE SHAREHOLDERS

      SECTION 3.1. ANNUAL MEETINGS. An annual meeting of the shareholders, for
the election of directors to succeed those whose terms expire and for the
transaction of such other business as may properly come before the meeting,
shall be held at such place, within or without the State of Texas, as may be
designated by the Board of Directors or officer calling the meeting at 10:00 in
the morning of the second Tuesday in June, or on such other date and time as the
Board of Directors or officer calling such meeting shall fix and set forth in
the notice of the meeting. At the annual meeting of the shareholders, only such
business shall be conducted as shall have been properly brought before the
annual meeting. To be properly brought before the annual meeting of
shareholders, business must be (i) specified in the notice of meeting (or any
supplement thereto) given by or at the direction of the Board of Directors, (ii)
otherwise properly brought before the meeting by or at the direction of the
Board of Directors, or (iii) otherwise properly brought before the meeting by a
shareholder of the Corporation who is a shareholder of record at the time of
giving of notice provided for in this Section 3.1, who shall be entitled to vote
at such meeting and who complies with the notice procedures set forth in this
Section



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<PAGE>

3.1. For business to be properly brought before an annual meeting by a
shareholder, the shareholder, in addition to any other applicable requirements,
must have given timely notice thereof in writing to the Secretary of the
Corporation. To be timely, a shareholder's notice must be delivered to or mailed
and received at the principal executive offices of the Corporation not less than
ninety (90) days prior to the anniversary date of the immediately preceding
annual meeting of shareholders of the Corporation. A shareholder's notice to the
Secretary shall set forth as to each matter the shareholder proposes to bring
before the annual meeting: (a) a brief description of the business desired to be
brought before the annual meeting and the reasons for conducting such business
at the annual meeting, (b) the name and address, as they appear on the
Corporation's books, of the shareholder proposing such business, (c) the class
and number of shares of voting stock of the Corporation which are beneficially
owned by the shareholder, (d) a representation that the shareholder intends to
appear in person or by proxy at the meeting to bring the proposed business
before the annual meeting, and (e) a description of any material interest of the
shareholder in such business. Notwithstanding anything in these Bylaws to the
contrary, no business shall be conducted at an annual meeting except in
accordance with the procedures set forth in this Section 3.1. The presiding
officer of an annual meeting shall, if the facts warrant, determine and declare
to the meeting that business was not properly brought before the meeting in
accordance with the provisions of this Section 3.1, and if he should so
determine, he shall so declare to the meeting and any such business not properly
brought before the meeting shall not be transacted.

      Notwithstanding the foregoing provisions of this Section 3.1, a
shareholder shall also comply with all applicable requirements of the Securities
Exchange Act of 1934, as amended, and the rules and regulations thereunder with
respect to the matters set forth in this Section 3.1.

      SECTION 3.2. SPECIAL MEETINGS. Except as otherwise provided by law or by
the Restated Articles of Incorporation, special meetings of the shareholders may
be called by the Chairman of the Board, the President, the Board of Directors,
or the holders of not less than one-tenth of all the shares having voting power
at such meeting, and shall be held at the principal office of the Corporation,
at such time as is stated in the notice calling such meeting, or at such other
place as the person or body calling such meeting may determine and state in such
notice.

      SECTION 3.3. NOTICE OF MEETINGS - WAIVER. Written, electronic or printed
notice, stating the place, day and hour of any meeting and, in case of a special
shareholders' meeting, the purpose or purposes for which the meeting is called,
shall be delivered not less than ten (10) nor more than fifty (50) days before
the date of the meeting by or at the direction of the Chairman of the Board, the
President, or the officer, body or person calling the meeting, to each
shareholder of record entitled to vote at such meeting. Notice shall be
delivered personally, by mail or, subject to receipt by the Corporation of
written authorization, electronic transmission. If delivered personally, such
notice shall be deemed delivered when actually received by the shareholder. If
delivered by mail, such notice shall be deemed delivered when deposited in the
United Sates mail addressed to



                                       3
<PAGE>

the shareholder at his address as it appears on the stock certificate register
of the Corporation, with postage thereon prepaid. If delivered by electronic
transmission, such notice shall be deemed delivered when the notice or the
location from which the notice can be retrieved or otherwise viewed is sent to
the electronic mail address specified by each shareholder that authorized
electronic transmission. Such further or earlier notice shall be given as may be
required by law. Waiver by a shareholder of notice in writing of a shareholders'
meeting, signed by him, whether before or after the time stated therein, shall
be equivalent to the giving of such notice. No notice shall be necessary for any
adjourned meeting.

      SECTION 3.4. CLOSING OF STOCK CERTIFICATE REGISTER AND FIXING RECORD DATE.
For the purpose of determining shareholders entitled to notice of or to vote at
any meeting of shareholders or any adjournment thereof, or entitled to receive
payment of any dividend or in order to make a determination of shareholders for
any other proper purpose, the Board of Directors of the Corporation may provide
that the stock certificate register shall be closed for a stated period but not
to exceed, in any case, fifty (50) days. If the stock certificate register shall
be closed for the purpose of determining shareholders entitled to notice of or
to vote at a meeting of shareholders, such registers shall be closed for at
least ten (10) days immediately preceding such meeting. In lieu of closing the
stock certificate register, the Board of Directors may fix in advance a date as
the record date for any such determination of shareholders, such date in any
case to be not more than fifty (50) days and, in case of a meeting of
shareholders, not less than ten (10) days prior to the date on which the
particular action, requiring such determination of shareholders, is to be taken.
If the stock certificate register is not closed and no record date is fixed for
the determination of shareholders entitled to notice of or to vote at a meeting
of shareholders, or shareholders entitled to receive payment of a dividend, the
date on which notice of the meeting is mailed or the date on which the
resolution of the Board of Directors declaring such dividend is adopted, as the
case may be, shall be the record date for such determination of shareholders.
When a determination of shareholders entitled to vote at any meeting of
shareholders has been made, as provided in this Section, such determination
shall apply to any adjournment thereof except where the determination has been
made through the closing of the stock certificate register and the stated period
of closing has expired.

      SECTION 3.5. VOTING LIST. The officer or agent having charge of the stock
certificate register for shares of the Corporation shall make, at least ten (10)
days before such meeting of shareholders, a complete list of the shareholders
entitled to vote at such meeting or any adjournment thereof, arranged in
alphabetical order, with the address of and the number of shares held by each,
which list, for a period of ten (10) days prior to such meeting, shall be kept
on file at the registered office of the Corporation and shall be subject to
inspection by any shareholder at any time during the usual business hours. Such
list shall also be produced and kept open at the time and place of the meeting
and shall be subject to the inspection of any shareholder during the whole time
of the meeting. Failure to comply with this Section shall not effect the
validity of any action taken at such meeting.



                                       4
<PAGE>

      SECTION 3.6. QUORUM AND OFFICERS. Except as otherwise provided by law, by
the Restated Articles of Incorporation or by these Bylaws, the holders of a
majority of the shares entitled to vote, represented in person or by proxy,
shall constitute a quorum at a meeting of shareholders, but the shareholders
present at any meeting, although less than a quorum, may from time to time
adjourn the meeting to some other day and hour, without notice other than
announcement at the meeting. The vote of the holders of a majority of the shares
entitled to vote and thus represented at a meeting at which a quorum is present
shall be the act of the shareholders' meeting, unless the vote of a greater
number is required by law, the Restated Articles of Incorporation or these
Bylaws. The Chairman of the Board, or in his absence, the President, shall
preside at and the Secretary, or in his absence, any Assistant Secretary shall
keep the records of each meeting of shareholders, and in the absence of all such
officers, their respective duties shall be performed by persons appointed by the
meeting.

      SECTION 3.7. PROXIES. A shareholder may vote either in person or by proxy
executed in writing by the shareholder, or by his duly authorized
attorney-in-fact. Proxies shall be dated but need not be sealed, witnessed or
acknowledged. No proxy shall be valid after eleven (11) months from the date of
its execution unless otherwise provided in the proxy. Each proxy shall be
revocable unless provided expressly therein to be irrevocable, and unless
otherwise made irrevocable by law. Proxies shall be filed with the Secretary of
the Corporation before or at the time of the meeting.

      SECTION 3.8. BALLOTING. Upon the demand of any shareholder, the vote upon
any question before the meeting shall be by ballot. At each meeting inspectors
of election may be appointed by the presiding officer of the meeting, and at any
meeting for the election of directors, inspectors shall be so appointed on the
demand of any shareholder present or represented by proxy and entitled to vote
at the election of directors. No director or candidate for the office of
directors shall be appointed as such inspector.

      SECTION 3.9. VOTING RIGHTS; VOTING FOR DIRECTORS. Each outstanding share
of common stock shall be entitled to one (1) vote upon each matter submitted to
a vote at a meeting of shareholders. No shareholder shall have the right to
cumulate his votes for the election of directors, but each share shall be
entitled to one vote in the election of each director.

      SECTION 3.10 NOMINATIONS FOR ELECTION AS A DIRECTOR. Only persons who are
nominated in accordance with the procedures set forth in these Bylaws and
qualify for nomination pursuant to Section 4.1 shall be eligible for election by
shareholders as, and to serve as, directors. Nominations of persons for election
to the Board of Directors of the Corporation may be made at a meeting of
shareholders (a) by or at the direction of the Board of Directors or a duly
constituted committee thereof or (b) by any shareholder of the Corporation who
is a shareholder of record at the time of giving of notice provided for in this
Section 3.10, who shall be entitled to vote for the election of directors at the
meeting and who complies with the notice procedures set forth in this Section
3.10. Such nominations, other than those made by or at the direction of the
Board of Directors, shall be made pursuant to timely notice in writing to the
Secretary of



                                       5
<PAGE>

the Corporation. To be timely, a shareholder's notice shall be delivered to or
mailed and received at the principal executive offices of the Corporation (i)
with respect to an election to be held at the annual meeting of the shareholders
of the Corporation, not less than ninety (90) days prior to the anniversary date
of the immediately preceding annual meeting of shareholders of the Corporation,
and (ii) with respect to an election to be held at a special meeting of
shareholders of the Corporation for the election of directors not later than the
close of business on the tenth (10th) day following the day on which notice of
the date of the special meeting was mailed to shareholders of the Corporation as
provided in Section 3.3 or public disclosure of the date of the special meeting
was made, whichever first occurs. Such shareholder's notice to the Secretary
shall set forth (x) as to each person whom the shareholder proposes to nominate
for election or re-election as a director, all information relating to such
person that is required to be disclosed in solicitations of proxies for election
of directors, or is otherwise required, pursuant to Regulation 14A under the
Securities Exchange Act of 1934, as amended (including such person's written
consent to being named in the proxy statement as a nominee and to serve as a
director if elected), and (y) as to the shareholder giving the notice (i) the
name and address, as they appear on the Corporation's books, of such shareholder
and (ii) the class and number of shares of voting stock of the Corporation which
are beneficially owned by such shareholder. At the request of the Board of
Directors, any person nominated by the Board of Directors for election as a
director shall furnish to the Secretary of the Corporation that information
required to be set forth in a shareholder's notice of nomination which pertains
to the nominee. In the event that a person is validly designated as a nominee to
the Board of Directors in accordance with the procedures set forth in this
Section 3.10 and shall thereafter become unable or unwilling to stand for
election to the Board of Directors, the Board of Directors or the shareholder
who proposed such nominee, as the case may be, may designate a substitute
nominee. Other than directors chosen pursuant to the provisions of Section 4.3,
no person shall be eligible to serve as a director of the Corporation unless
nominated in accordance with the procedures set forth in this Section 3.10. The
presiding officer of the meeting of shareholders shall, if the facts warrant,
determine and declare to the meeting that a nomination was not made in
accordance with the procedures prescribed by these Bylaws, and if he should so
determine, he shall so declare to the meeting and the defective nomination shall
be disregarded. Notwithstanding the foregoing provisions of this Section 3.10, a
shareholder shall also comply with all applicable requirements of the Securities
Exchange Act of 1934, as amended, and the rules and regulations thereunder with
respect to the matters set forth in this Section 3.10.

                                   ARTICLE IV

                             THE BOARD OF DIRECTORS

      SECTION 4.1. NUMBER AND QUALIFICATIONS. The business and affairs of the
Corporation shall be managed and controlled by the Board of Directors, and
subject to any restrictions imposed by law, by the Restated Articles of
Incorporation, or by these Bylaws, the Board of Directors may exercise all the
powers of the Corporation. The



                                       6
<PAGE>

Board of Directors shall consist of eleven (11) members. The number thereof may
be increased or decreased from time to time by amendment to these Bylaws, but no
decrease shall have the effect of shortening the term of any incumbent director.
Directors need not be residents of Texas and need not be shareholders. Directors
shall retire as of the date of the annual meeting of shareholders first
occurring following the Director's 73rd birthday; provided, that any Director
who was originally elected on or before June 19, 1981 shall not be required to
retire until the date of the annual meeting of shareholders first occurring
following such Director's 75th birthday. No person shall be qualified for
election or re-election as a director of the Corporation if he is an incumbent
director and has attended fewer than fifty (50%) percent of the meetings of the
Board of Directors held during any fiscal year commencing after January 31,
1981, which such incumbent was entitled to attend as a director.

      SECTION 4.2. CLASSIFICATION AND TERM. The Board of Directors shall be
divided into three classes, each class consisting as nearly as possible of
one-third (1/3) of the number of directors that make up the full Board of
Directors. At each annual meeting of shareholders, the number of directors equal
to the number of the class whose term expires at the time of such meeting shall
be elected to hold office until the third succeeding annual meeting of
shareholders.

      SECTION 4.3. VACANCIES. Any vacancy on the Board of Directors may be
filled by the vote of a majority of the remaining directors though less than a
quorum of the Board of Directors; provided, that the Board of Directors may not
fill more than two (2) vacancies caused by an increase in the number of
directors during any period between two (2) successive annual meetings of
shareholders. A director elected to fill a vacancy shall hold office for the
unexpired portion of his predecessor's term if such vacancy was created by the
death, resignation, disqualification or removal of a director or until the next
annual meeting of shareholders if such vacancy was created by an increase in the
size of the Board of Directors.

      SECTION 4.4. PLACE OF MEETING. Meetings of the Board of Directors may be
held either within or without the State of Texas, at whatsoever place is
specified by the officer or director calling the meeting. In the absence of
other designation, the meeting shall be held at the principal business office of
the Corporation.

      SECTION 4.5. REGULAR MEETINGS. The Board of Directors shall hold no fewer
than four (4) regular meetings in each fiscal year. One such regular meeting
(the "Annual Meeting of Directors") shall be held immediately following the
annual meeting of shareholders, at the place of such shareholder meeting, and
the other regular meetings shall be held at such times and places as the Board
of Directors shall establish by resolution at the regular meeting following the
annual meeting of shareholders. No notice of any kind of such regular meetings
shall be necessary to either old or new members of the Board of Directors.

      SECTION 4.6. SPECIAL MEETINGS. Special meetings of the Board of Directors
shall be held at any time by call of the Chairman of the Board, the President
(if a director) or by



                                       7
<PAGE>

a majority of the directors. The Secretary or officer performing his duties
shall give notice of special meetings to each director at his usual business or
residence address by mailing such notice at least five (5) days or one hundred
twenty (120) hours before the meeting or by personally delivering or, subject to
receipt of written authorization, electronically transmitting the same at least
one (1) day or twenty-four (24) hours before the meeting. No notice shall be
necessary for any adjourned meeting. A waiver of notice of any special meeting,
in writing, signed by the person or persons entitled to such notice, whether
before or after the time stated therein, shall be equivalent to the giving of
such notice. Such notice or waiver thereof need not specify the business to be
transacted at, or the purpose of, such meeting. Attendance of a director at a
meeting shall constitute a waiver of notice of such meeting, except where a
director attends a meeting for the express and announced purpose of objecting to
the transaction of any business on the ground that the meeting is not lawfully
called or convened.

      SECTION 4.7. QUORUM. Seven directors shall constitute a quorum for the
transaction of business. The act of a majority of the directors present at a
meeting at which a quorum is in attendance shall be the act of the Board of
Directors unless a larger number is required by applicable law, the Restated
Articles of Incorporation or these Bylaws, but any one or more directors,
although less than a quorum, may adjourn the meeting to some other day or hour.

      SECTION 4.8. CHAIRMAN OF THE BOARD. At each Annual Meeting of Directors,
the Board of Directors shall elect from its membership a Chairman of the Board
who shall serve in such capacity until the next Annual Meeting of Directors or
until his death, resignation, disqualification or removal if sooner. The
Chairman of the Board shall preside at all meetings of the Board of Directors
and at all meetings of the shareholders of the Company.

      SECTION 4.9. PROCEDURE AT MEETINGS. The Chairman of the Board shall
preside at meetings of the Board of Directors. In his absence at any meeting,
the President (if a director) shall preside, and in the absence of both the
Chairman of the Board and the President, a member of the Board of Directors
selected by the members present shall preside. The Secretary of the Corporation
shall act as secretary at all meetings of the Board, or in his absence the
presiding officer of the meeting may designate any person to act as secretary.
At meetings of the Board of Directors, business shall be transacted in such
order as from time to time the Board of Directors may determine.

      SECTION 4.10. PRESUMPTION OF ASSENT. A director of the Corporation who is
present at a meeting of the Board of Directors at which action on any corporate
matter is taken shall be presumed to have assented to the action taken unless
his dissent shall be entered in the minutes of the meeting or unless he shall
file his written dissent to such action with the person acting as the secretary
of the meeting before the adjournment thereof or shall forward such dissent by
registered mail to the Secretary of the Corporation immediately after the
adjournment of the meeting. Such right to dissent shall not apply to a director
who voted in favor of such action.



                                       8

<PAGE>

      SECTION 4.11. COMPENSATION. Directors as such shall not receive any stated
salary for their service, but by resolution of the Board of Directors (a) an
annual directors fee and (b) a fixed sum and expenses for attendance, if any,
may be allowed to each director who is not an officer or employee of the
Corporation for attendance at each regular or special meeting of the Board of
Directors or of any Committee thereof; but nothing herein shall preclude any
director from serving the Corporation in any other capacity or receiving
compensation therefor.

      SECTION 4.12. STANDING COMMITTEES. The Board of Directors by resolution
adopted by a majority of the number of directors fixed by the Bylaws shall
designate from their number an Executive Committee and an Audit Committee.

      The Executive Committee shall consist of five (5) persons. Each member
shall serve until the next annual meeting of shareholders or until such
director's retirement, removal, disqualification, or death. The Executive
Committee shall meet upon the call of the chairman of such committee or any two
(2) members thereof and shall have and may exercise all of the authority of the
Board of Directors in the business and affairs of the Corporation except (a) the
power to authorize or approve the sale or other transfer of any real property
now owned or hereafter acquired by the Corporation; (b) the power to vote,
direct the vote or grant proxies relating to any stock owned by the Corporation;
(c) the power to authorize or approve purchases or commitments for goods or
services with an aggregate market value in any single transaction or group of
related transactions exceeding $5,000,000 except for goods and services
purchased in the ordinary course of business for inventory or pursuant to
capital expenditure budgets approved by the Board of Directors; (d) the power to
authorize or approve the incurrence or guaranty of indebtedness with an original
principal amount in excess of $1,000,000 and a maturity of longer than one (1)
year; (e) the power to make loans, guaranties, investments, or other commitments
outside the ordinary course of business in excess of $5,000,000 at any time
outstanding to any one person or group of persons; and (f) where action of the
Board of Directors is specified by the Texas Business Corporation Act or by
other applicable law.

      The Audit Committee shall consist of four (4) persons, all of whom shall
be independent of management and free of any relationship that, in the opinion
of the Board of Directors, would interfere with the exercise of independent
judgment as a committee member. Each member shall serve until the next annual
meeting of shareholders or until such director's retirement, removal,
disqualification, or death. The Audit Committee shall meet no fewer than two (2)
times in each fiscal year of the Corporation upon the call of the chairman of
such committee or any two (2) members thereof and shall have and may exercise
such responsibilities, authority and power as the Board of Directors specifies.

      The designation of Standing Committees and delegation of authority thereto
shall not operate to relieve the Board of Directors, or any member thereof, of
any responsibility imposed upon it or him by law.

      SECTION 4.13. OTHER COMMITTEES OF THE BOARD OF DIRECTORS. The Board of
Directors, by resolution adopted by a majority of the number of directors fixed
by the


                                       9
<PAGE>

Bylaws, may designate from their number such compensation, nominating and other
committees as they shall, from time to time, deem necessary and proper. Such
committees shall be composed of not less than three members and shall have and
exercise such of the Board of Directors' authority as shall by resolution, be
delegated to it. The designation of such other committees and the delegation of
authority thereto shall not operate to relieve the Board of Directors, or any
member thereof, of any responsibility imposed upon it or him by law.

      SECTION 4.14. MEETINGS AND REPORTS OF THE COMMITTEES. The Committees shall
meet from time to time as set forth in the Bylaws and on call of the Chairman or
any two or more members thereof. Notice of each such meeting, stating the place,
day and hour thereof, shall be served personally on each member of such
Committee, or shall be mailed, delivered, telephoned or, subject to receipt of
written authorization, electronically transmitted to his address on the books of
the Corporation, at least twenty-four (24) hours before the meeting. No such
notice need state the business proposed to be transacted at the meeting. No
notice of the time or place of any meeting of such Committee need be given to
any member thereof who attends in person or who, in writing executed and filed
with the records of the meeting either before or after the holding thereof,
waives such notice. No notice need be given of an adjourned meeting of any
Committee. Meetings of the Committees may be held at such place or places,
either within or outside of the State of Texas, as such Committee shall
determine, or as may be specified or fixed in the respective notices or waivers
thereof. Each Committee may fix its own rules of procedure. They shall keep
record of their proceedings and shall report these proceedings to the Board of
Directors at the regular meetings thereof held next after they have been taken.

      SECTION 4.15. ADVISORY DIRECTORS. The Board of Directors, by resolution
adopted by a majority of the number of directors fixed by the Bylaws, may
appoint from those persons who have previously served as a director of the
Corporation, such advisory directors as the Board of Directors may, from time to
time, determine to be desirable. Such advisory directors shall be ex-officio
members of the Board of Directors, shall hold office from the date elected until
the next following annual meeting of the Board of Directors unless sooner
removed in the manner provided for the removal of Directors, shall be entitled
to receive notice of and to attend all meetings of the Board of Directors and
shall be reimbursed for all out-of-pocket expenses incurred to attend meetings
of the Board of Directors. Advisory directors shall not be a member of any
committee of the Board of Directors, vote on any matter brought before the Board
of Directors for action or be counted for the purposes of determining whether a
quorum exists. Failure to notify the advisory directors of any meeting shall not
render any meeting or any action taken at such meeting void.



                                       10
<PAGE>

                                    ARTICLE V

                                    OFFICERS

      SECTION 5.1. NUMBER. The officers of the Corporation shall consist of the
President, Secretary, Treasurer and Controller; and, in addition, such Vice
Presidents, other officers and assistant officers and agents as may be deemed
necessary and elected or appointed by the Board of Directors. The Board of
Directors may by resolution designate any officer as the Chief Executive
Officer, Chief Financial Officer, Chief Accounting Officer, or other title. Any
two or more offices may be held by the same person.

      SECTION 5.2. ELECTION; TERM; QUALIFICATION. Officers shall be chosen by
the Board of Directors at the Annual Meeting of the Directors and may be chosen
at any other meeting of the Board of Directors. Each officer shall hold office
until the next following Annual Meeting of Directors, or until his death,
resignation, retirement or removal.

      SECTION 5.3. REMOVAL. Any officer or agent elected or appointed by the
Board of Directors may be removed by the Board of Directors at its pleasure, but
such removal shall be without prejudice to other contract rights, if any, of the
person so removed. Election or appointment of an officer or agent shall not of
itself create any contract rights.

      SECTION 5.4. RETIREMENT. No person may serve as an officer of the
Corporation after the last day of the fiscal year in which such officer
celebrates his sixty-fifth birthday or such later date as is necessary to comply
with applicable laws.

      SECTION 5.5. VACANCIES. Any vacancy in any office for any cause may be
filled by the Board of Directors at any meeting.

      SECTION 5.6. DUTIES. The officers of the Corporation shall have such
powers and duties, except as modified by the Board of Directors, as generally
pertain to their offices, respectively, as well as such powers and duties as
from time to time shall be conferred by the Board of Directors and by these
Bylaws.

      SECTION 5.7. THE PRESIDENT. The President shall, subject to the control of
the Board of Directors, have general supervision and control over all of the
business, assets and affairs of the Corporation. All other officers shall report
as directed by the President. In the absence of the Chairman of the Board, the
President shall perform all of the duties of the Chairman of the Board, and when
so acting shall have all of the powers of, and be subject to all restrictions
upon, the Chairman of the Board.

      SECTION 5.8. SECRETARY. The Secretary shall: (a) keep the minutes of all
meetings of the shareholders, of the Board of Directors, and of all committees
of the Board of Directors, in one or more books provided for that purpose and
shall distribute a copy of all such minutes to the members of the Board of
Directors immediately on receipt thereof, (b) see that all notices are duly
given in accordance with the provisions of these



                                       11
<PAGE>

Bylaws or as required by law, (c) be custodian of the corporate records and of
the seal of the Corporation and see that the seal of the Corporation is affixed
to all documents the execution of which on behalf of the Corporation under its
seal is duly authorized, (d) have general charge of the stock certificate
register, transfer books and stock ledgers, and such other books and papers as
the Board of Directors may direct, of the Corporation, all of which shall, at
all reasonable times, be open to the examination of any director, upon
application at the office of the Corporation during business hours, and (e) in
general perform all duties and exercise all powers incident to the office of the
Secretary and such other duties and powers as the Board of Directors or the
President from time to time may assign to or confer on him.

      SECTION 5.9. TREASURER. The Treasurer shall be legal custodian of all
monies, notes, securities, and other valuables which may from time to time come
into the possession of the Corporation and shall perform such other duties as
the Bylaws may require or the Board of Directors may prescribe. The Treasurer
shall have the power and authority to incur or guaranty indebtedness on behalf
of the Corporation without the prior approval of the Board of Directors provided
that the original principal amount thereof is less than $1,000,000 and the
original maturity is less than one year.

      SECTION 5.10. CONTROLLER. The Controller shall keep complete and accurate
books and records of account showing accurately at all times the financial
condition of the Corporation. He shall furnish at meetings of the Board of
Directors, or whenever requested, a statement of the financial condition of the
Corporation, and shall perform such other duties as the Bylaws may require or
the Board of Directors may prescribe.

      SECTION 5.11. THE VICE PRESIDENTS. The Board of Directors may from time to
time elect such Vice Presidents as the Board of Directors deems appropriate and
assign thereto such general or specific powers, authority and responsibility as
the Board of Directors deems appropriate. The Board of Directors may specify the
order in which the Vice Presidents may act in the absence of the President. Any
action taken by a Vice President in the performance of the duties of President
shall be conclusive evidence of the absence of the President. The Vice
Presidents shall perform such other duties as may, from time to time, be
assigned to them by the Board of Directors or the President. A Vice President
may also sign with the Secretary or an Assistant Secretary certificates of stock
of the Corporation.

      SECTION 5.12. ASSISTANT OFFICERS. Any Assistant Secretary, Assistant
Treasurer or Assistant Controller appointed by the Board of Directors shall have
power to perform, and shall perform, all duties incumbent upon the Secretary,
the Treasurer or the Controller of the Corporation, respectively, subject to the
general direction of such officers, and shall perform such other duties as the
Bylaws may require or the Board of Directors may prescribe.

      SECTION 5.13. SALARIES. The salaries or other compensation of the officers
shall be fixed from time to time by the Board of Directors. No officer shall be
prevented from



                                       12
<PAGE>

receiving such salary or other compensation by reason of the fact that he is
also a director of the Corporation.

      SECTION 5.14. BONDS OF OFFICERS. The Board of Directors may secure the
fidelity of any or all of such officers by bond or otherwise, in such terms and
with such surety or sureties, conditions, penalties or securities as shall be
required by the Board of Directors.

      SECTION 5.15. DELEGATION. The Board of Directors may delegate temporarily
the powers and duties of any officer of the Corporation, in case of his absence
or for any other reason, to any other officer, and may authorize the delegation
by any officer of the Corporation of any of his powers and duties to any agent
or employee subject to the general supervision of such officer.

                                   ARTICLE VI

                                  MISCELLANEOUS

      SECTION 6.1. CONTRACTS. The Board of Directors may authorize any officer
or officers, agent or agents, of the Corporation to enter into any contract or
execute and deliver any instrument in the name of or on behalf of the
Corporation, and such authority may be general or confined to specific
instances; and, unless so authorized by the Board of Directors or by these
Bylaws, no officer, agent or employee shall have any power or authority to bind
the Corporation by any contract or engagement, or to pledge its credit or to
render it liable pecuniarily for any purpose or to any amount.

      SECTION 6.2. CHECKS, DRAFTS, ETC. All checks, drafts, or other orders for
the payment of money, notes, or other evidences of indebtedness issued in the
name of the Corporation shall be signed by such officers or employees of the
Corporation as shall from time to time be authorized pursuant to these Bylaws or
by resolution of the Board of Directors.

      SECTION 6.3. DEPOSITORIES. All funds of the Corporation shall be deposited
from time to time to the credit of the Corporation in such banks, trust
companies, or other depositories as the Board of Directors may from time to time
designate, upon such terms and conditions as shall be fixed by the Board of
Directors. The Board of Directors may from time to time authorize the opening
and keeping with any such depository as it may designate of general and special
bank accounts, and may make such special rules and regulations with respect
thereto, not inconsistent with the provisions of these Bylaws, as it may deem
expedient.

      SECTION 6.4. ENDORSEMENT OF STOCK CERTIFICATES. Subject to the specific
directions of the Board of Directors, any share or shares of stock issued by any
corporation and owned by the Corporation (including reacquired shares of the
Corporation) may, for sale or transfer, be endorsed in the name of the
Corporation by the President or any Vice President, and attested or witnessed by
the Secretary or any Assistant Secretary either with or without affixing the
corporate seal.


                                       13
<PAGE>

      SECTION 6.5. VOTING OF SHARES OWNED BY THE CORPORATION. Subject to the
direction of the Board of Directors, the President, the Secretary and the
Treasurer, or any of them, shall have the power and authority on behalf of the
Corporation to attend and to vote and to grant proxies to be used at any meeting
of shareholders of any corporation in which the Corporation may hold stock. The
Board of Directors may confer like powers upon any other person or persons.

      SECTION 6.6. CORPORATE SEAL. The corporate seal shall be in the form of a
five pointed star surrounded by the words "Stewart & Stevenson Services, Inc.,"
and such seal, or a facsimile thereof, may be impressed on, affixed to, or in
any manner reproduced upon, instruments of any nature required to be executed by
officers of the Corporation.

      SECTION 6.7. FISCAL YEAR. The fiscal year of the Corporation shall begin
on February 1 and end on January 31 of the next following year, or on such other
dates as the Board of Directors at any time shall determine.

      SECTION 6.8. RESIGNATIONS. Any director or officer may resign at any time.
Such resignations shall be made in writing and shall take effect at the time
specified therein, or, if no time be specified, at the time of its receipt by
the Chairman of the Board, President or Secretary. The acceptance of a
resignation shall not be necessary to make it effective, unless expressly so
provided in the resignation.

      SECTION 6.9. INDEMNIFICATION OF OFFICERS AND DIRECTORS. The Corporation
shall indemnify any person against any judgment, penalty, fine, settlement and
reasonable expenses incurred by him in connection with any threatened, pending
or completed action, suit or proceeding in which such person is or is threatened
to be made a party because he is or was serving as an officer or director of the
Corporation or at the request of the Corporation as an officer, director,
partner, venturer, proprietor, trustee, employee, agent or other functionary of
another entity and (i) such person is wholly successful in the defense thereof,
or (ii) it is determined in the manner required by law that such person
conducted himself in good faith, reasonably believed that his conduct was in the
best interest of the Corporation and had no reasonable cause to believe that his
conduct was unlawful; provided, however, that no person shall be indemnified if
such indemnity is prohibited by applicable law. Any such indemnification shall
be reported in writing to the shareholders of the Corporation on or before the
notice or waiver of notice of the next shareholders' meeting and in any event
within twelve (12) months of the indemnification. The right of indemnification
under this Section 6.9 shall be in addition to any other rights to which such
persons may be entitled and is intended to provide the broadest benefits
permitted by law.

      SECTION 6.10. LOANS TO AND GUARANTIES FOR OFFICERS AND DIRECTORS. The
Corporation shall not lend money to or guaranty the indebtedness of any of its
officers or directors unless such loan or guaranty is approved by the number of
directors equal to a majority of the full Board of Directors none of whom are
then or will become as a result of



                                       14
<PAGE>

such action indebted to the Corporation and on the express finding by such
directors that such loan or guaranty is reasonably expected to directly or
indirectly benefit the Corporation.

                                   ARTICLE VII

                                   AMENDMENTS

      SECTION 7.1. AMENDMENTS. The Board of Directors, by the affirmative vote
of seven directors may alter, amend or repeal these Bylaws or adopt new Bylaws.
The shareholders by affirmative vote of two-thirds (2/3) of the issued and
outstanding shares entitled to vote may alter, amend or repeal these Bylaws or
adopt new Bylaws, without notice at any regular meeting, or if notice of the
proposed amendment be contained in the notice of any special meeting.



                                       15

<PAGE>

                  FIRST AMENDMENT TO THE SIXTH RESTATED BYLAWS
                      OF STEWART & STEVENSON SERVICES, INC.


Effective as of April 28, 2000, Section 4.1 and 4.7 of the Bylaws of Stewart &
Stevenson Services, Inc. was amended to read as follows:

      SECTION 4.1. NUMBER AND QUALIFICATIONS. The business and affairs of the
      Corporation shall be managed and controlled by the Board of Directors, and
      subject to any restrictions imposed by law, by the Restated Articles of
      Incorporation, or by these Bylaws, the Board of Directors may exercise all
      the powers of the Corporation. The Board of Directors shall consist of
      twelve (12) members. The number thereof may be increased or decreased from
      time to time by amendment to these Bylaws, but no decrease shall have the
      effect of shortening the term of any incumbent director. Directors need
      not be residents of Texas and need not be shareholders. Directors shall
      retire as of the date of the annual meeting of shareholders first
      occurring following the Director's 73rd birthday; provided, that any
      Director who was originally elected on or before June 19, 1981 shall not
      be required to retire until the date of the annual meeting of shareholders
      first occurring following such Director's 75th birthday. No person shall
      be qualified for election or re-election as a director of the Corporation
      if he is an incumbent director and has attended fewer than fifty (50%)
      percent of the meetings of the Board of Directors held during any fiscal
      year commencing after January 31, 1981, which such incumbent was entitled
      to attend as a director.

      SECTION 4.7. QUORUM. Eight directors shall constitute a quorum for the
      transaction of business. The act of a majority of the directors present at
      a meeting at which a quorum is in attendance shall be the act of the Board
      of Directors unless a larger number is required by applicable law, the
      Restated Articles of Incorporation or these Bylaws, but any one or more
      directors, although less than a quorum, may adjourn the meeting to some
      other day or hour.



                                       16

<PAGE>

                  SECOND AMENDMENT TO THE SIXTH RESTATED BYLAWS
                      OF STEWART & STEVENSON SERVICES, INC.


Effective as of June 13, 2000, the first sentence in the third paragraph of
Section 4.12 Standing Committees of the Sixth Restated Bylaws of the Company was
amended to read as follows:

      "The Audit Committee shall consist of five (5) persons, all of whom shall
      be independent of management and free of any relationship that, in the
      opinion of the Board of Directors, would interfere with the exercise of
      independent judgment as a committee member."



                                       17
<PAGE>

                  THIRD AMENDMENT TO THE SIXTH RESTATED BYLAWS
                      OF STEWART & STEVENSON SERVICES, INC.


Effective as of September 12, 2000, Section 4.1 of the Sixth Restated Bylaws of
the Company is amended to read as follows in its entirety:

      SECTION 4.1. NUMBER AND QUALIFICATIONS. The business and affairs of the
      Corporation shall be managed and controlled by the Board of Directors, and
      subject to any restrictions imposed by law, by the Restated Articles of
      Incorporation, or by these Bylaws, the Board of Directors may exercise all
      the powers of the Corporation. The Board of Directors shall consist of
      thirteen (13) members, PROVIDED, HOWEVER, that such number shall be
      automatically reduced to twelve (12) upon the retirement, resignation,
      death or removal of a director on or after September 12, 2000. The number
      thereof may be increased or decreased from time to time by amendment to
      these Bylaws, but no decrease shall have the effect of shortening the term
      of any incumbent director. Directors need not be residents of Texas and
      need not be shareholders. Directors shall retire as of the date of the
      annual meeting of shareholders first occurring following the Director's
      73rd birthday; PROVIDED, that any Director who was originally elected on
      or before June 19, 1981 shall not be required to retire until the date of
      the annual meeting of shareholders first occurring following such
      Director's 75th birthday. No person shall be qualified for election or
      re-election as a director of the Corporation if he is an incumbent
      director and has attended fewer than fifty percent (50%) of the meetings
      of the Board of Directors held during any fiscal year commencing after
      January 31, 1981, which such incumbent was entitled to attend as a
      director.



                                       18
<PAGE>

                  FOURTH AMENDMENT TO THE SIXTH RESTATED BYLAWS
                      OF STEWART & STEVENSON SERVICES, INC.


Effective as of December 11, 2000, Section 5.4 Retirement of the Sixth Restated
Bylaws of the Company is deleted.



                                       19
<PAGE>

                  FIFTH AMENDMENT TO THE SIXTH RESTATED BYLAWS
                      OF STEWART & STEVENSON SERVICES, INC.


Effective June 12, 2001, Section 4.1 Number and Qualifications, Section 4.7
Quorum and the first sentence in the third paragraph of Section 4.12 Standing
Committees of the Sixth Restated Bylaws of the Company are amended to read as
follows in their entirety:

      SECTION 4.1. NUMBER AND QUALIFICATIONS. The business and affairs of the
      Corporation shall be managed and controlled by the Board of Directors, and
      subject to any restrictions imposed by law, by the Restated Articles of
      Incorporation, or by these Bylaws, the Board of Directors may exercise all
      the powers of the Corporation. The Board of Directors shall consist of ten
      (10) members. The number thereof may be increased or decreased from time
      to time by amendment to these Bylaws, but no decrease shall have the
      effect of shortening the term of any incumbent director. Directors need
      not be residents of Texas and need not be shareholders. Directors shall
      retire as of the date of the annual meeting of shareholders first
      occurring following the Director's 73rd birthday. No person shall be
      qualified for election or re-election as a director of the Corporation if
      he is an incumbent director and has attended fewer than fifty (50%)
      percent of the meetings of the Board of Directors held during any fiscal
      year.

      SECTION 4.7. QUORUM. Six directors shall constitute a quorum for the
      transaction of business. The act of a majority of the directors present at
      a meeting at which a quorum is in attendance shall be the act of the Board
      of Directors unless a larger number is required by applicable law, the
      Restated Articles of Incorporation or these Bylaws, but any one or more
      directors, although less than a quorum, may adjourn the meeting to some
      other day or hour.

First sentence in the third paragraph of SECTION 4.12 STANDING COMMITTES:

      The Audit Committee shall consist of not less than three (3) directors who
      are qualified and independent of management and free of any relationship
      that, in the opinion of the Board of Directors, would interfere with the
      exercise of independent judgment as a committee member.



                                       20