This Amendment No. 2 to Amended and Restated Employment Agreement
("Amendment") is made and entered into on March 20, 1998, between DYNAMEX INC.,
a Delaware corporation, hereinafter referred to as the "Company," and RICHARD K.
MCCLELLAND, hereinafter referred to as "Executive."
         WHEREAS, Executive and the Company have entered into an Amended and
Restated Employment Agreement, dated as of July 11, 1995, as amended by
Amendment No. 1 thereto, dated as of July 1, 1996 and effective as of September
27, 1995 (as amended, the "Agreement"); and
         WHEREAS, the parties hereto mutually desire to amend certain provisions
of the Agreement;
         NOW, THEREFORE, the parties hereto agree as follows.
         1.       On December 20, 1995, Parcelway Systems Holding Corp. changed
its name to Dynamex Inc. The name "Parcelway Systems Holding Corp." shall be
replaced with "Dynamex Inc." wherever it appears in the Agreement, and the
defined term "Holdings" shall be replaced with the term "Dynamex" wherever it
appears in the Agreement.
         2.       Section 4 of the Agreement shall hereinafter read as follows:
                  "4. Grant Options.
                          (a)      The Company has granted to Executive stock 
                  options (the "Grant Options") for the purchase of 48,000
                  shares (reflecting the 4 for 1 split of Common Stock effective
                  on June 3, 1996) of the Dynamex Common Stock at an exercise
                  price of US $4.25 per share ("Exercise Price") pursuant to the
                  form of option agreement attached hereto as Exhibit B. The
                  shares of Dynamex Common Stock that are to be issued to
                  Executive upon exercise of the Grant Options shall be referred
                  to herein as the "Grant Shares."
                          (b)      The Company shall pay Executive eight equal
                  bonus payments each in the amount of $25,500 plus interest as
                  calculated herein, with the first such payment to be made on
                  the last day of the third month following Executive's exercise
                  of the Grant Options (the "Exercise Date") and remaining
                  payments to be made on the last day of each succeeding
                  three-month period, respectively, with the eighth and last
                  such payment to be made on the eighteen month anniversary of
                  the initial payment date. Interest shall be paid along with
                  each bonus payment and shall accrue from the date the Grant
                  Options are exercised 
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                  on the unpaid balance of all such bonus payments at the rate
                  announced publicly by NationsBank of Texas, N.A. in Dallas,
                  Texas, from time to time as its prime rate.
                  (c)     If this Agreement is terminated after the Exercise 
         Date for any reason other than those set forth in Section 2(a), 2(c) or
         2(d), then the entire principal amount of the Option Bonus that is due
         and unpaid on such termination date, shall become immediately due and
         payable to Executive.
         3.       Except as set forth above, the other provisions of the 
Agreement shall remain in full force and effect.
         4.       This Amendment shall be governed by and construed in
accordance with the laws of Delaware.
         EXECUTED the day, month and year first above written.
                                  DYNAMEX INC.
                                           Robert P. Capps, Vice President
                                               Richard K. McClelland