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                                                                  EXHIBIT 10.28

                                    AGREEMENT

         AGREEMENT, dated April 24, 2001, by and between United Auto Group,
Inc., a Delaware Corporation (the "Company"), and Marshall S. Cogan ("MSC").

         WHEREAS, the Company and MSC are parties to a Non-Competition and
Standstill Agreement (the "Non-Competition Agreement"), dated as of April 12,
1999, whereby, among other things, MSC is subject to various restrictions with
respect to the capital stock of the Company and competing with the Company;

         WHEREAS, pursuant to the Non-Competition Agreement, the Company is
required to make certain payments to MSC (the "Non-Compete Payments"); and

         WHEREAS, the Company desires to terminate its obligations to make the
Non-Compete Payments to MSC.

         NOW THEREFORE, in consideration of the premises and the mutual
agreements contained herein and in the Release (as defined below), the parties
hereto agree as follows:

         1.       Amendment to Non-Compete. Clause (c) of the last sentence of
                  Section 3(a) (No Competing Business) of the Non-Competition
                  Agreement is hereby amended to read as follows:

                           (c) within the continental United States or Puerto
                           Rico, participate or engage, directly or indirectly,
                           for himself or on behalf of or in conjunction with
                           any person, corporation, partnership or other entity,
                           whether as an employee, agent, or investor with a
                           greater than $500,000,000 equity interest, in any
                           business activities (a "Competitive Activity") if
                           such activity constitutes the production,
                           distribution, sale, service or provision of products
                           or services that are similar to products or services
                           then being produced, distributed, sold, serviced or
                           otherwise provided by the Company or any of its
                           subsidiaries as of the date of this Agreement.

         2.       Termination of Non-Compete Payments. Section 6 (Consideration)
                  of the Non-Competition Agreement is hereby deleted and is of
                  no further force and effect.

         3.       Release. Concurrently with the execution and delivery of this
                  Agreement, MSC has executed and delivered to the Company a
                  general release (the "Release") in the form of Exhibit A
                  attached hereto.
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         4.       Payment to MSC. Immediately following the execution and
                  delivery of this Agreement, the Company shall pay MSC
                  $4,000,000 by wire transfer of immediately available funds.

         5.       Resignation. Concurrently with the execution and delivery of
                  this Agreement, MSC has resigned from the Board of Directors
                  of the Company.

         6.       Stock Options. The option granted to MSC on January 14, 2000
                  to purchase 25,000 shares of common stock of the Company, par
                  value $0.0001 per share, shall hereby be modified so that (i)
                  the portion thereof that has not as of the date hereof vested
                  and become exercisable shall immediately vest and become
                  exercisable upon execution and delivery of this Agreement and
                  (ii) such option shall be exercisable until January 14, 2010.
                  Such option shall in all other respects remain subject to the
                  terms of the First Amended and Restated United Auto Group,
                  Inc. Stock Option Plan and the stock option agreement entered
                  into in connection with such grant.

         7.       Consultation with Counsel. MSC acknowledges that he has had
                  the opportunity to consult with a lawyer (of his own choosing
                  and at his own expense) before executing and delivering this
                  Agreement and the Release and that he has executed and
                  delivered this Agreement and the Release voluntarily and free
                  from any coercion or duress.

         8.       MSC's Representations. MSC hereby represents to the Company as
                  follows: MSC has all requisite power and authority to enter
                  into and perform all of his obligations under this Agreement
                  and the Release; this Agreement and the Release represent
                  valid and binding obligations on MSC's part, enforceable in
                  accordance with their terms; this Agreement and the Release
                  have been duly executed and delivered by MSC; and the
                  execution, delivery and performance of this Agreement and the
                  Release by MSC will not constitute a violation of, conflict
                  with or result in a default under (i) any contract,
                  understanding or arrangement to which MSC is a party or by
                  which MSC is bound, (ii) any judgment, decree or order
                  applicable to MSC, or (iii) any law, rule or regulation of any
                  governmental body applicable to MSC.

         9.       The Company's Representations. The Company represents to MSC
                  as follows: the Company is a corporation duly formed and in
                  good standing under the laws of the State of Delaware; it has
                  all requisite corporate power and authority to enter into and
                  perform all its obligations under this Agreement; the
                  execution and delivery of this Agreement and the consummation
                  of the transactions contemplated hereby have been duly

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                  authorized by all necessary corporate action on the part of
                  the Company; this Agreement has been duly executed and
                  delivered by the Company; this Agreement constitutes a valid
                  and binding agreement on the part of the Company, enforceable
                  in accordance with its terms; and the execution, delivery and
                  performance of this Agreement by the Company will not
                  constitute a violation of, conflict with or result in a
                  default under (i) any contract, understanding or arrangement
                  to which the Company is a party or by which the Company is
                  bound, (ii) any judgment, decree or order applicable to the
                  Company, or (iii) any law, rule or regulation of any
                  governmental body applicable to the Company.

         10.      Governing Law. This Agreement and the Release shall be
                  governed by and construed in accordance with the laws of the
                  State of New York, without giving effect to the choice of law
                  provisions thereof.

         11.      Further Assurances. MSC and the Company shall perform such
                  further acts and execute such further documents as may
                  reasonably be required to carry out the provisions of this
                  Agreement and the Release.

         12.      Assignability. Neither this Agreement nor the Release may be
                  assigned by either party, except that the Company may assign
                  any and all of its rights and obligations under this Agreement
                  or the Release to one or more of its affiliates or to any
                  parent or subsidiary corporation of the Company (in which
                  case, references to the Company in this Agreement or the
                  Release shall be deemed to be references to its permitted
                  assignee); provided, that, no such assignment by the Company
                  shall relieve the Company of its obligations hereunder.

         13.      Entire Agreement. This Agreement and the Release constitute
                  the entire agreement and supersede all prior agreements and
                  understandings, oral or written, between MSC and the Company
                  with respect to the subject matter hereof.

         14.      Effect of Invalidity. Any term or provision of this Agreement
                  or the Release which is unenforceable in any jurisdiction
                  shall, as to such jurisdiction, be ineffective to the extent
                  of such unenforceability without rendering invalid or
                  unenforceable the remaining terms and provisions of this
                  Agreement or the Release or affecting the validity or
                  enforceability of any of the terms or provisions of this
                  Agreement or the Release in any other jurisdiction. If any
                  provision of this Agreement or the Release is so broad as to
                  be unenforceable, such provision shall be interpreted to be
                  only so broad as is enforceable.

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         15.      Counterparts. This Agreement may be executed in counterparts,
                  each of which shall be an original, but all of which together
                  shall constitute one and the same agreement.

                                     UNITED AUTO GROUP, INC.

                                     By:  /s/ Robert H. Kurnick, Jr.
                                          --------------------------------------
                                          Name:Robert H. Kurnick, Jr.
                                          Title:Executive Vice President

                                     MARSHALL S. COGAN

                                     By:  /s/ Marshall S. Cogan
                                          --------------------------------------

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                                                                       EXHIBIT A

                                 GENERAL RELEASE

         1. In consideration of the payments and benefits to be provided to
Marshall S. Cogan ("MSC") pursuant to the Termination Agreement (the
"Termination Agreement"), as of even date herewith, by and between MSC and
United Auto Group, Inc., a Delaware corporation (the "Company"), the sufficiency
of which is acknowledged hereby, MSC, with the intention of binding himself and
his heirs, executors, administrators and assigns, does hereby release, remise,
acquit and forever discharge the Company and each of its subsidiaries and
affiliates (the "Company Affiliated Group"), their present and former officers,
directors, executives, agents, attorneys and employees, and the successors,
predecessors and assigns of each of the foregoing (collectively, the "Released
Parties"), of and from any and all claims, actions, causes of action,
complaints, charges, demands, rights, damages, debts, sums of money, accounts,
financial obligations, suits, expenses, attorneys' fees and liabilities of
whatever kind or nature in law, equity or otherwise, whether accrued, absolute,
contingent, unliquidated or otherwise and whether now known or unknown,
suspected or unsuspected, which MSC, individually or as a member of a class, now
has, owns or holds, or has at any time heretofore had, owned or held, against
any Released Party arising out of or in any way connected with MSC's service to
any member of the Company Affiliated Group (or the predecessors thereof) in any
capacity, or the termination of such service in any such capacity, excepting
only:

                  (A)      the obligations of the Company under the Termination
                           Agreement; and

                  (B)      any rights to indemnification MSC may have under (i)
                           applicable corporate law or (ii) the by-laws or
                           certificate of incorporation of any Released Party or
                           as an insured under any director's and officer's
                           liability insurance policy now or previously in
                           force.

         2. This Release applies to any relief no matter how called, including,
without limitation, wages, back pay, front pay, compensatory damages, liquidated
damages, punitive damages, damages for pain or suffering, costs, and attorney's
fees and expenses.

                                /s/ Marshall S. Cogan
                                ------------------------------------------------
                                Marshall S. Cogan

                                Dated: April 24, 2001
                                      ------------------------------------------

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                                   RESIGNATION

         I, Marshall S. Cogan, hereby resign as director of United Auto Group,
         Inc. effective immediately as of the date hereof.

                                /s/ Marshall S. Cogan
                                ------------------------------------------------
                                Marshall S. Cogan

                                Dated: April 24, 2001
                                      ------------------------------------------<PAGE>   1
                                                                   EXHIBIT 10.01

                               AMENDMENT NO. 1 TO
                         EXECUTIVE EMPLOYMENT AGREEMENT

                               (JOHN R. EICKHOFF)

This Amendment, dated as of April 18, 2001, amends certain provisions of the
Executive Employment Agreement ("Agreement"), dated as of March 30, 2001,
between Ceridian Corporation and John R. Eickhoff ("Executive"). Unless
otherwise defined herein, capitalized terms used in this Amendment have the
meanings given to them in the Agreement. In consideration of you continuing in
your employment with Ceridian for the remaining term of the Agreement, and the
mutual promises and obligations contained in the Agreement as modified by this
Amendment, Executive and Ceridian agree to amend the Agreement as follows:

1.       Section 2.03 of the Agreement shall be amended in its entirety to read
         as follows:

         "2.03    TERM. Subject to the provisions of Articles IV, VII, and VIII,
                  this Agreement and Executive's employment shall continue until
                  the later of: (a) December 31, 2002; and (b) two years after a
                  Change of Control which occurs prior to December 31, 2002."

2.       This Amendment is governed by, and shall be construed in accordance
         with, the laws of the State of Minnesota.

3.       Except as herein expressly amended, the Agreement is ratified and
         confirmed in all respects and shall remain in full force and effect in
         accordance with its terms.

4.       This Amendment may be executed in two or more counterparts, each of
         which shall be deemed an original, but all of which together shall
         constitute one and the same instrument.

Ceridian and Executive have caused this Amendment to be duly executed and
delivered, and this Amendment shall be effective, as of the date first written
above. Following the effectiveness of this Amendment, each reference in the
Agreement to "this Agreement," "hereunder," "herein," "hereof," or words of like
import shall mean and be a reference to the Agreement as amended by this
Amendment.

EXECUTIVE                          CERIDIAN CORPORATION

/s/ John R. Eickhoff               By: /s/ Shirley J. Hughes
John R. Eickhoff                   Title: Senior Vice President, Human Resources

Address:

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