William D. Zollars
 
                             EMPLOYMENT AGREEMENT
 
 
         AGREEMENT, made this 15th day of December, 1999, by and between Yellow
Corporation, a Delaware corporation ("Yellow"), and William D. Zollars (the
"Executive").
 
                                   WITNESSETH
 
         WHEREAS, the Board of Directors of Yellow has approved the employment
of the Executive on the terms and conditions set forth in this Agreement; and
 
         WHEREAS, the Executive is willing, for the consideration provided, to
enter into employment with Yellow on the terms and conditions set forth in this
Agreement;
 
         NOW, THEREFORE, the parties, intending to be legally bound, agree as
follows:
 
1.       Employment. Yellow hereby agrees to employ the Executive, and the
         Executive hereby accepts such employment, upon the terms and conditions
         set forth in this Agreement.
 
2.       Term. The term of this Agreement shall be for two (2) years from the
         date hereof (the "Effective Date"), with said term renewing daily, and
         ending on the date of termination of the Executive's employment
         determined pursuant to Section 5, 6 or 7, whichever shall be
         applicable.
 
3.       Position and Duties. The Executive shall serve as Chairman, President
         and CEO of Yellow, and shall have such responsibilities and authority
         as commensurate with such offices and as may from time to time be
         prescribed by or pursuant to Yellow's bylaws. The Executive shall
         devote
 
 
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         substantially all of his working time and efforts to the business and
         affairs of Yellow.
 
4.       Compensation. During the period of the Executive's employment, Yellow
         shall provide the Executive with the following compensation and other
         benefits:
 
         (a)  Base Salary. Yellow shall pay to the Executive base salary at the
              initial rate of $550,000 per annum, retroactive to November 8,
              1999, which shall be payable in accordance with the standard
              payroll practices of Yellow. Such base salary rate shall be
              reviewed annually in accordance with Yellow's normal policies
              beginning in calendar year 2000; provided, however, that at no
              time during the term of this Agreement shall the Executive's base
              salary be decreased from the rate then in effect except (i) in
              connection with across-the-board reductions similarly affecting
              substantially all senior executives of Yellow or (ii) with the
              written consent of the Executive.
 
         (b)  Annual Bonus.
 
              (1)  For Calendar Year 1999. Executive shall receive a Bonus for
                   calendar year 1999, calculated as follows:
 
                   (i)  For the period January 1, 1999 through November 7, 1999,
                        Executive's Bonus shall be calculated utilizing the
                        formula adopted for Senior Management Executive Bonuses
 
 
 
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                        at Yellow's subsidiary, Yellow Freight System, Inc.,
                        based upon the salary received by Executive in his
                        position as President of that subsidiary for this
                        period.
 
                   (ii) For the period November 8, 1999 through December 31,
                        1999, Executive's Bonus shall be calculated utilizing
                        the formula previously adopted by the Compensation
                        Committee for the position of Chairman, President and
                        CEO of Yellow based upon the salary received by
                        Executive for these positions under this Agreement and
                        for this period.
 
              (2)  For Calendar Year 2000 and Beyond. The Executive shall
                   participate in a bonus program established and maintained by
                   Yellow pursuant to which a threshold award for each fiscal
                   year is 18.75% of the Executive's base salary; a target award
                   is 75% of base salary; and a maximum award is 150% of base
                   salary in respect of each fiscal year of Yellow commencing
                   with 2000, provided that any payment under such award shall
                   be conditioned upon satisfaction of the threshold. The
                   criteria for establishment of the threshold and target and
                   the parameters for payments
 
 
 
 
 
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                   at, above or below the target shall be determined annually by
                   the Compensation Committee of the Board of Directors of
                   Yellow. At least 80% of the criteria established by the
                   Compensation Committee which would result in a payment of 75%
                   of base salary to the Executive shall be based on specific
                   measurements of financial performance of Yellow during the
                   applicable fiscal year and the remaining percentage may be
                   based on non-financial criteria.
 
              (c)  Stock Options. Yellow has granted to the Executive, effective
                   as of the Effective Date, an option to purchase 200,000
                   shares of Common Stock of Yellow, with an option term of ten
                   years and an option price per share equal to the closing
                   price of a share of Common Stock of Yellow as reported on the
                   NASDAQ National Market System on the Effective Date;
                   provided, however, that such option shall vest and become
                   exercisable at the rate of (i) 25% on the first anniversary
                   of the Effective Date; (ii) 25% on the second anniversary of
                   the Effective Date; (iii) 25% on the third anniversary of the
                   Effective Date; and (iv) 25% on the fourth anniversary of the
                   Effective Date. With respect to succeeding years, the
                   Compensation Committee of the Board of Directors of Yellow
                   shall determine the number of stock options, if any, to be
                   granted to the Executive and the terms and conditions of any
                   such options.
 
 
 
 
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              (d)  Supplemental Retirement Benefits. Yellow shall provide
                   Executive with supplemental retirement benefits in accordance
                   with this subsection (d) and Appendix A pursuant to which the
                   Executive shall receive from Yellow upon his termination of
                   employment with Yellow (and subject to the vesting provision
                   hereinafter set forth), the difference between (i) the
                   monthly benefit that he would have received under Section 4.4
                   of the Yellow Freight Office, Clerical, Sales and Supervisory
                   Personnel Pension Plan (the "Pension Plan") (calculated as a
                   single life annuity payable commencing at his Normal
                   Retirement Date as defined under the Pension Plan with an
                   actuarial reduction if payment commences prior to his Normal
                   Retirement Date) using 20 years of Credit Service as defined
                   under the Pension Plan plus his actual Credited Service
                   credited under the Pension Plan after five (5) years from
                   September 6, 1996, the date of Executive's commencement of
                   employment with Yellow's subsidiary, Yellow Freight System,
                   Inc., and using Compensation as defined in Section 2.1(h) (2)
                   of the Pension Plan, including Compensation previously earned
                   during his employment with Yellow Freight System, Inc. from
                   September 6, 1996 through November 7, 1999, but without any
                   reduction under Section 401(a) (17) of the Internal Revenue
                   Code of 1986, as amended )the "Code") and (ii) the monthly
                   benefit actually payable to the Executive under Section
 
 
 
 
 
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              4.4 of the Pension Plan, calculated at the time the Executive
              commences payment of a Vested Pension under the Pension Plan, if
              any. The Executive shall vest in the supplemental retirement
              benefit described in this subsection (d) at the rate of 20% per
              year commencing on September 6, 1997 (so that he would become 100%
              vested on September 6, 2001), provided, however, that the
              Executive shall forfeit any unvested portion in the event of the
              termination of his employment prior to becoming 100% vested.
              Notwithstanding the foregoing, the Executive shall immediately
              become 100% vested in the event of the termination of his
              employment under circumstances entitling the Executive to benefits
              pursuant to Section 8. The supplemental retirement benefit
              described in this subsection (d) and Appendix A shall be payable
              monthly commencing as of the last day of the month following the
              month of termination of the Executive's employment or, if
              Executive has not yet qualified for payment of a retirement
              benefit under the Pension Plan as of his date of termination, the
              supplemental retirement benefit shall be payable monthly
              commencing as of the earliest date of Executive's eligibility to
              retire under the Pension Plan subject to actuarial reduction for
              payments commencing prior to Executive's normal retirement date,
              and shall continue until the Executive's death. Upon the
              Executive's death, if at the time of his death he had already
 
 
 
 
 
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              qualified for payment of a retirement benefit under the Pension
              Plan and if he is survived by and still married to the person who
              was his spouse on September 6, 1996, the monthly supplemental
              retirement benefit payable to the Executive during his life shall
              continue to said surviving spouse until her death. If at the time
              of his death, the Executive had not yet qualified for payment of a
              retirement benefit under the Pension Plan, if he is survived by
              and still married to the person who was his spouse on September 6,
              1996, said spouse shall qualify to receive the same monthly
              supplemental retirement benefit commencing on the last day of the
              month in which Executive would have reached his Normal Retirement
              Date. If the Executive at the time of his death is neither
              survived by or not married to the person who was his spouse on
              September 6, 1996, no further supplemental retirement benefits
              shall be payable under this subsection (d) following his death.
              The Executive acknowledges that these supplemental retirement
              benefits are an element of the compensation to be paid for his
              services and not an unfunded plan of deferred compensation within
              the meaning of Section 201 of the Employee Retirement Income
              Security Act, as amended.
 
         (e)  Other Benefits. In addition to the compensation and benefits
              otherwise specified in this Agreement, the Executive (and, if
              provided for under the applicable plan or program, his spouse)
 
 
 
 
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              shall be entitled to participate in, and to receive benefits
              under, Yellow's employee benefit plans and programs that are or
              may be available to senior executives generally and on terms and
              conditions that are no less favorable than those generally
              applicable to other senior executives of Yellow. At no time during
              the term of this Agreement shall the Executive's participation in
              or benefits received under such plans and programs be decreased
              except (i) in connection with across-the-board reductions
              similarly affecting substantially all senior executives of Yellow
              or (ii) with the written consent of the Executive. The Executive
              shall be treated as having satisfied any otherwise applicable
              waiting period requirement for coverage under Yellow's disability
              insurance plan, effective as of the Effective Date.
 
         (f)  Expenses. The Executive shall be entitled to prompt reimbursement
              of all reasonable expenses incurred by him in performing services
              hereunder, provided he properly accounts therefore in accordance
              with Yellow's policies.
 
         (g)  Office and Services Furnished. Yellow shall furnish the Executive
              with office space, secretarial assistance and such other
              facilities and services as shall be suitable to the Executive's
              position and adequate for the performance of his duties hereunder.
 
5.       Termination of Employment by Yellow.
 
 
 
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         (a)  Cause. Yellow may terminate the Executive's employment for Cause
              if the Executive willfully engages in conduct which is materially
              and demonstrably injurious to Yellow or if the Executive willfully
              engages in an act or acts of dishonesty resulting in material
              personal gain to the Executive at the expense of Yellow. Yellow
              shall exercise its right to terminate the Executive's employment
              for Cause by (i) giving him written notice of termination at least
              30 days before the date of such termination specifying in
              reasonable detail the circumstances constituting such Cause; and
              (ii) delivering to the Executive a copy of a resolution duly
              adopted by the affirmative vote of not less than a majority of the
              entire membership of the Board of Directors (except the
              Executive), after reasonable notice to the Executive and an
              opportunity for the Executive and his counsel to be heard before
              the Board of Directors, finding that the Executive has engaged in
              the conduct set forth in this subsection (a). In the event of such
              termination of the Executive's employment for Cause, the Executive
              shall be entitled to receive (i) his base salary pursuant to
              Section 4(a) and any other compensation and benefits to the extent
              actually earned pursuant to this Agreement or any benefit plan or
              program of Yellow as of the date of such termination at the normal
              time for payment of such salary, compensation or benefits and (ii)
              any amounts owing under Section 4 (f). In addition, in the event
              of
 
 
 
 
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              such termination of the Executive's employment for Cause, all
              outstanding options held by the Executive at the effective date of
              such termination which had not already been exercised shall be
              forfeited. Except as provided in Section 9, the Executive shall
              receive no other compensation or benefits from Yellow.
 
         (b)  Disability. If the Executive incurs a Permanent and Total
              Disability, as defined below, Yellow may terminate the Executive's
              employment by giving him written notice of termination at least 30
              days before the date of such termination. In the event of such
              termination of the Executive's employment because of Permanent and
              Total Disability, (i) the Executive shall be entitled to receive
              his base salary pursuant to Section 4(a) and any other
              compensation and benefits to the extent actually earned by the
              Executive pursuant to this Agreement or any benefit plan or
              program of Yellow as of the date of such termination of employment
              at the normal time for payment of such salary, compensation or
              benefits, and any amounts owing under Section 4(f), and (ii) all
              outstanding stock options held by the Executive at the time of his
              termination of employment shall become immediately exercisable at
              that time, and the Executive shall have one year from the date of
              such termination of employment to exercise any or all of such
              outstanding options (but not beyond the term of such option). For
              purposes of this Agreement, the
 
 
 
 
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              Executive shall be considered to have incurred a Permanent and
              Total Disability if he is unable to engage in any substantial
              gainful employment by reason of any materially determinable
              physical or mental impairment which can be expected to result in
              death or which has lasted or can be expected to last for a
              continuous period of not less than 12 months. The existence of
              such Permanent and Total Disability shall be evidenced by such
              medical certification as the Secretary of Yellow shall require and
              shall be subject to the approval of the Compensation Committee of
              the Board of Directors of Yellow.
 
         (c)  Without Cause. Yellow may terminate the Executive's employment at
              any time and for any reason, other than for Cause or because of
              Permanent and Total Disability, by giving him a written notice of
              termination to that effect at least 30 days before the date of
              termination. In the event of such termination of the Executive's
              employment without Cause, the Executive shall be entitled to the
              benefits described in Section 8.
 
6.       Termination of Employment by the Executive.
 
         a.   Good Reason. The Executive may terminate his employment for Good
              Reason by giving Yellow a written notice of termination at least
              30 days before the date of such termination specifying in
              reasonable detail the circumstances constituting such Good Reason.
              In the event of the Executive's termination of his
 
 
 
 
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              employment for Good Reason, the Executive shall be entitled to the
              benefits described in Section 8. For purposes of this Agreement,
              Good Reason shall mean the failure of Yellow in any material way
              either (i) to pay or provide to the Executive the compensation and
              benefits that he is entitled to receive pursuant to this Agreement
              by the later of (A) 60 days after the applicable due date or (B)
              30 days after the Executive's written demand for payment, or (ii)
              to maintain the titles, positions and duties of the Executive
              commensurate with those titles and positions and as required by
              this Agreement except with the Executive's written consent, or
              (iii) Executive's receipt of notice from Yellow of the cut-off of
              the automatic renewal of the term of this Agreement as described
              in Section 2 above.
 
         b.   Following A Change of Control. The Executive may terminate his
              employment at any time within the three-month period which begins
              six months after a Change of Control of Yellow by giving Yellow a
              written notice of such termination at least 30 days before the
              date of termination. In the event of the Executive's termination
              of employment within such three-month period, the Executive shall
              be entitled to the benefits described in Section 8. For purposes
              of this Agreement, a Change of Control of Yellow shall be deemed
              to have taken place if: (i) a third person, including a "group" as
              defined in Section 13(d) (3) of the Securities Exchange
 
 
 
 
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              Act of 1934, purchases or otherwise acquires shares of Yellow
              after the date hereof and as a result thereof becomes the
              beneficial owner of shares of Yellow having 20% or more of the
              total number of votes that may be cast for the election of
              directors of Yellow; or (ii) as the result of, or in connection
              with any cash tender or exchange offer, merger or other Business
              Combination, or contested election, or any combination of the
              foregoing transactions, the Continuing Directors shall cease to
              constitute a majority of the Board of Directors of Yellow or any
              successor to Yellow. For this purpose, (i) Business Combination
              means any transaction which is referred to in any one or more of
              clauses (a) through (e) of Section 1 of Subparagraph A of Article
              Seventh of the Certificate of Incorporation of Yellow, and (ii)
              Continuing Director means a director of Yellow who meets the
              definition of Continuing Director contained in Section 7 of
              Subparagraph C of Article Seventh of the Certificate of
              Incorporation of Yellow.
 
         c.   Other. The Executive may terminate his employment at any time and
              for any reason, other than pursuant to subsection (a) or (b)
              above, by giving Yellow a written notice of termination to that
              effect at least 30 days before the date of termination. In the
              event of the Executive's termination of his employment pursuant to
              this subsection (c), the Executive shall be entitled to receive
              (i) his base salary pursuant to Section 4(a) and any other
              compensation and
 
 
 
 
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              benefits to the extent actually earned by the Executive pursuant
              to this Agreement or any benefit plan or program of Yellow as of
              the date of such termination at the normal time for payment of
              such salary, compensation or benefits, and (ii) any amounts owing
              under Section 4(f). In addition, in the event of the Executive's
              termination of his employment pursuant to this subsection (c), (i)
              all outstanding options held by the Executive at the time of such
              termination which had not already become exercisable shall be
              forfeited, and (ii) all outstanding options held by the Executive
              at the time of such termination which had already become
              exercisable shall expire 90 days after the date of such
              termination (or, if earlier, upon the expiration of the term of
              the option). Except as provided in Section 9, the Executive shall
              receive no other compensation or benefits from Yellow.
 
7.       Termination of Employment By Death. In the event of the death of the
         Executive during the course of his employment hereunder, (i) the
         Executive's estate shall be entitled to receive his base salary
         pursuant to Section 4(a) and any other compensation and benefits to the
         extent actually earned by the Executive pursuant to this Agreement or
         any other benefit plan or program of Yellow as of the date of such
         termination at the normal time for payment of such salary, compensation
         or benefits, and any amounts owing under Section 4(f), (ii) any death
         benefit due under the Pension Plan and any death benefit due under
         Section 4(d) shall be paid to
 
 
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         the Executive's spouse as provided under Section 4(d) and (iii) all
         outstanding stock options held by the Executive at the time of his
         death shall become immediately exercisable upon his death, and the
         Executive's spouse or, if predeceased, the Executive's estate, shall
         have one year from the date of his death to exercise any or all of such
         outstanding options (but not beyond the term of such option).
 
8.       Benefits Upon Termination Without Cause, For Good Reason, or Following
         Change of Control. If the Executive's employment with Yellow shall
         terminate (i) because of termination by Yellow pursuant to Section 5(c)
         and not for Cause or because of Permanent and Total Disability, (ii)
         because of termination by the Executive for Good Reason pursuant to
         Section 6(a), or (iii) because of termination by the Executive within
         the three-month period which begins six months after a Change of
         Control of Yellow pursuant to Section 6(b), the Executive shall be
         entitled to the following:
 
         (a)  Yellow shall pay to the Executive his base salary pursuant to
              Section 4 (a) and, subject to the further provisions of this
              Section 8, any other compensation and benefits to the extent
              actually earned by the Executive under this Agreement or any
              benefit plan or program of Yellow as of the date of such
              termination at the normal time for payment of such salary,
              compensation or benefits.
 
         (b)  Yellow shall pay the Executive any amounts owing under Section
              4(f).
 
 
 
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         (c)  Yellow shall pay to the Executive as a severance benefit an amount
              equal to twice the sum of (i) his annual rate of base salary
              immediately preceding his termination of employment, and (ii) the
              target bonus payable pursuant to subsection (d) below. Such
              severance benefit shall be paid in a lump sum within 30 days after
              the date of such termination of employment.
 
         (d)  Yellow shall pay to the Executive his target bonus under Yellow's
              target bonus plan for the fiscal year in which his termination of
              employment occurs as if the target had been exactly met. Such
              payment shall be made in a lump sum within 30 days after the date
              of such termination of employment, and the Executive shall have no
              right to any further bonuses under said program.
 
         (e)  The Executive shall become 100% vested in all benefits accrued to
              the date of termination of his employment but not previously paid
              under the supplemental retirement benefits pursuant to Section
              4(d), and Yellow's nonqualified defined contribution plans.
              Payment of benefits under such plans, and under the Pension Plan
              and Yellow's qualified defined contribution plans, shall be made
              at the time and in the manner determined under the applicable
              plan.
 
         (f)  During the period of 24 months beginning on the date of the
              Executive's termination of employment, the Executive (and, if
              applicable under the applicable program, his spouse) shall remain
              covered by the employee benefit plans and programs that covered
 
 
 
 
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              him immediately prior to his termination of employment as if he
              had remained in employment for such period, provided, however,
              that there shall be excluded for this purpose any plan or program
              providing payment for time not worked (including without
              limitation holiday, vacation, and long- and short-term
              disability). In the event that the Executive's participation in
              any such employee benefit plan or program is barred, Yellow shall
              arrange to provide the Executive with substantially similar
              benefits. Any medical insurance coverage for such two-year period
              pursuant to this subsection (f) shall become secondary upon the
              earlier of (i) the date on which the Executive begins to be
              covered by comparable medical coverage provided by a new employer,
              or (ii) the earliest date upon which the Executive becomes
              eligible for Medicare or a comparable Government insurance
              program.
 
         (g)  All outstanding stock options held by the Executive at the time of
              termination of his employment shall become fully exercisable upon
              such termination of employment and may be exercised for the
              balance of the term of such option.
 
         (h)  If any payment or benefit received by or in respect of the
              Executive under this Agreement or any other plan, arrangement or
              agreement with Yellow (determined without regard to any additional
              payments required under this subsection (h) and Appendix B of this
              Agreement) (a "Payment") would be subject to
 
 
 
 
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         the excise tax imposed by Section 4999 of the Internal Revenue Code of
         1986, as amended (the "Code") (or any similar tax that may hereafter be
         imposed) or any interest or penalties are incurred by the Executive
         with respect to such excise tax (such excise tax, together with any
         such interest and penalties, being hereinafter collectively referred to
         as the "Excise Tax"), Yellow shall pay to the Executive with respect to
         such Payment at the time specified in Appendix B an additional amount
         (the "Gross-up Payment") such that the net amount retained by the
         Executive from the Payment and the Gross-up Payment, after reduction
         for any Excise Tax upon the payment and any federal, state and local
         income and employment tax and Excise Tax upon the Gross-up Payment,
         shall be equal to the Payment. The calculation and payment of the
         Gross-up Payment shall be subject to the provisions of Appendix B.
 
9.       Entitlement To Other Benefits. Except as provided in this Agreement,
         this Agreement shall not be construed as limiting in any way any rights
         to benefits that the Executive may have pursuant to any other plan or
         program of Yellow.
 
10.      Arbitration.
 
         (a)  Arbitration of Disputes. Any dispute between the parties hereto
              arising out of, in connection with, or relating to this Agreement
              or the breach thereof shall be settled by arbitration in Overland
              Park,
 
 
 
 
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              Kansas, in accordance with the rules then in effect of the
              American Arbitration Association ("AAA"). Arbitration shall be the
              exclusive remedy for any such dispute except only as to failure to
              abide by an arbitration award rendered hereunder. Regardless of
              whether or not both parties hereto participate in the arbitration
              proceeding, any arbitration award rendered hereunder shall be
              final and binding on each party hereto and judgment upon the award
              rendered may be entered in any court having jurisdiction thereof.
 
              The party seeking arbitration shall notify the other party in
              writing and request the AAA to submit a list of 5 or 7 potential
              arbitrators. In the event the parties do not agree upon an
              arbitrator, each party shall, in turn, strike one arbitrator from
              the list, Yellow having the first strike, until only one
              arbitrator remains, who shall arbitrate the dispute. The parties
              shall have the opportunity to conduct reasonable discovery as
              determined by the arbitrator, and the arbitration hearing shall be
              conducted within 30 to 60 days of the selection of an arbitrator
              or at the earliest date thereafter that the arbitrator is
              available or as otherwise set by the arbitrator.
 
         b.   Indemnification. If arbitration occurs as provided for herein and
              the Executive is awarded more than Yellow has asserted is due him
              or otherwise substantially prevails therein, Yellow shall
              reimburse the Executive for his reasonable attorneys' fees, costs
              and
 
 
 
 
 
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              disbursements incurred in such arbitration and hereby agrees to
              pay interest on any money award obtained by the Executive from the
              date payment should have been made until the date payment is made,
              calculated at the prime interest rate of Bank of America, Inc.,
              Kansas City, Missouri in effect from time to time from the date
              that payment(s) to him should have been made under this Agreement.
              If the Executive enforces the arbitration award in court, Yellow
              shall reimburse the Executive for his reasonable attorneys' fees,
              costs and disbursements incurred in such enforcement.
 
11.      Confidential Information. The Executive shall retain in confidence any
         confidential information known to him concerning Yellow and its
         subsidiaries, and their respective businesses until such information is
         publicly disclosed. This provision shall survive the termination of the
         Executive's employment for any reason under this Agreement.
 
12.      Indemnification under Bylaws. Yellow shall provide the Executive with
         rights to indemnification by Yellow that are no less favorable to the
         Executive than those set forth in Yellow's by-laws as in effect as of
         the Effective Date.
 
13.      Successors. This Agreement shall be binding upon and insure to the
         benefit of the Executive and his estate and Yellow and any successor of
         Yellow, but neither this Agreement nor any rights arising hereunder may
         be assigned or pledged by the Executive.
 
 
 
 
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14.      Severability. Any provision in this Agreement which is prohibited or
         unenforceable in any jurisdiction shall, as to such jurisdiction, be
         ineffective only to the extent of such prohibition or unenforceability
         without invalidating or affecting the remaining provisions hereof, and
         any such prohibition or unenforceability in any jurisdiction shall not
         invalidate or render unenforceable such provision in any other
         jurisdiction.
 
15.      Notices. All notices required or permitted to be given under this
         Agreement shall be given in writing and shall be deemed sufficiently
         given if delivered by hand or mailed by registered mail, return receipt
         requested, to his residence in the case of the Executive and to its
         principal executive offices in the case of Yellow. Either party may by
         giving written notice to the other party in accordance with this
         Section 15 change the address at which it is to receive notices
         hereunder.
 
16.      Controlling Law. This Agreement shall in all respects by governed by
         and construed in accordance with the laws of the State of Kansas.
 
17.      Changes to Agreement. This Agreement may not be changed orally but only
         in a writing, signed by the party against whom enforcement is sought.
 
18.      Counterparts. This Agreement may be executed in any number of
         counterparts, each of which when so executed shall be deemed an
         original but all of which together shall constitute one and the same
         instrument.
 
19.      Prior Agreement. Except as regards the commencement date for
         Executive's Supplemental Retirement Benefits, as discussed in Section
         4(d) above, this Agreement in all respects supercedes and replaces the
 
 
 
 
 
 
                                       21
<PAGE>   22
 
         Employment Agreement entered into between Executive and Yellow Freight
         System, Inc. on September 6, 1996.
 
       IN WITNESS WHEREOF, the parties have executed this Agreement on the
21 of December, 1999.
 
 
EXECUTIVE:                                        YELLOW CORPORATION
 
/s/ William D. Zollers
- ----------------------------                 By:  /s/ William F. Martin
                                                ---------------------------
                                                  ATTEST
 
                                             By:  /s/ Lawrence D. Berkowitz
                                                ---------------------------
 
 
 
 
                                       22
<PAGE>   23
 
 
 
                                   Appendix A
                        Supplemental Retirement Benefits
 
 
         The following provisions shall be applicable with respect to the
supplemental retirement benefits described in Section 4(e) of this Agreement.
 
1.       Benefit Calculation
 
         For purposes of calculating the supplemental retirement benefits, the
         following assumptions shall be utilized.
 
         (a)  "Credited Service", shall be assumed to be twenty (20) years
              for periods of employment prior to five (5) years of employment
              measured from September 6, 1996, plus actual Credited Service, if
              any, for periods of employment after five (5) years of employment
              measured from September 6, 1996 and Executive's Compensation for
              the period September 6, 1996 through November 7, 1999 shall be the
              Compensation earned by Executive during his employment with Yellow
              Freight System, Inc.
 
         (b)  If the Executive is employed by Yellow for less than five (5)
              years from September 6, 1996, "Average Final Compensation" shall
              be calculated as the average "base wage" as so defined in Section
              2.1(h)(2) of the Plan for actual number of years of employment,
              with partial years annualized;
 
         (c)  Any vested accrued benefit which the Executive is paid under
              the Pension Plan, shall reduce any supplement retirement benefits
              payable under this Agreement; and
 
         (d)  The defined terms used in this Appendix A and in Section 4(e)
              of this Agreement shall have the meanings provided in the Yellow
              Freight Office, Clerical, Sales and Supervisory Personnel Pension
              Plan as restated as of January 1, 1989 and as amended by Amendment
              No. 1 dated July 15, 1992, by Amendment No. 2 dated December 28,
              1994, all as in existence as of the Effective Date of this
              Agreement (collectively the "Pension Plan") unless another meaning
              is expressly provided in this Agreement and Appendix or unless the
              Executive and Yellow agree in writing to apply any subsequent
              amendments, revisions, interpretations or restatements of the
              Pension Plan.
 
 
 
                                       23
<PAGE>   24
 
 
 
2.       Vesting
 
         Notwithstanding the vesting provisions of Section 4(d), the Executive
         shall become 100% vested in the supplemental retirement benefits
         provided under that subsection and this Appendix upon the termination
         of his employment for any of the following reasons:
 
         (a)  Termination by Yellow without "Cause",
 
         (b)  Termination by the Executive for "Good Reason", or
 
         (c)  The Executive's resignation within the three month period
              which begins six months after a "Change of Control" of Yellow,
 
              "Cause", "Good Reason", and "Change of Control" shall have the
              respective meanings as defined in Section 5, 6(a) and 6(b) of this
              Agreement.
 
3.       Taxability of Benefit
 
         The Executive and Yellow understand and agree that for federal tax
         purposes, all supplemental retirement benefits paid under this
         agreement to the Executive or his spouse shall be treated as ordinary
         income under the applicable provisions of the Internal Revenue Code of
         1986, as amended, and are subject to any taxes required to be withheld
         by federal, state or local law; provided that the Executive shall have
         the right to determine the timing of any withholding within the
         parameters permitted under the Code and under any Regulations or
         proposed Regulations under Code Section 3121(v) or any successor
         thereto.
 
4.       Nonassignability
 
         The supplemental retirement benefits payable under this Agreement, and
         any and all rights thereto, shall not be subject in any manner to
         anticipation, alienation, sale, transfer, assignment, pledge,
         encumbrance, charge, garnishment, execution, or levy of any kind,
         either voluntarily or involuntarily. Any attempt to anticipate,
         alienate, sell, transfer, assign, pledge, encumber, charge, or
         otherwise dispose of any rights to benefits payable hereunder shall be
         void.