GATX CORPORATION
 
                        CASH INCENTIVE COMPENSATION PLAN
 
                                   SECTION 1
 
                                    GENERAL
 
     1.1.  Purpose.  The purpose of the GATX Corporation Cash Incentive
Compensation Plan (the "Plan") is to promote the long term financial interest of
GATX Corporation (the "Company") by (i) attracting and retaining executive
personnel possessing outstanding ability; (ii) further motivating such
individuals by means of cash incentives to achieve long-range goals; and (iii)
providing cash incentive compensation opportunities which are competitive with
those of other major corporations.
 
     1.2.  Participation.  Subject to the terms and conditions of the Plan, the
Committee shall determine and designate, from time to time, from among the
Eligible Employees, those persons who will be granted one or more Cash Incentive
Awards under the Plan, and thereby become "Participants" in the Plan.
 
     1.3.  Operation, Administration, and Definitions.  The operation and
administration of the Plan, including the Cash Incentive Awards made under the
Plan, shall be subject to the provisions of Section 4 (relating to operation and
administration). Capitalized terms in the Plan shall be defined as set forth in
the Plan (including the definition provisions of Section 8).
 
                                   SECTION 2
 
                              CASH INCENTIVE AWARD
 
     2.1.  Designation.  The Committee, from time to time in its discretion,
shall designate from among the Eligible Employees those individuals who will
have an opportunity to receive Cash Incentive Awards under the Plan for any
Performance Period, together with the amounts to be distributed in accordance
with Section 3. Except as otherwise provided by the Committee, Cash Incentive
Awards are intended to be Performance-Based Compensation. Any Cash Incentive
Awards intended to be Performance-Based Compensation shall comply with the
requirements of this Section 2 to the extent such compliance is determined by
the Committee to be required for the Cash Incentive Awards to be treated as
Performance-Based Compensation. To the extent that the provisions of this
Section 2 reflect the requirements applicable to Performance-Based Compensation,
such provisions shall not apply to the portion of any Cash Incentive Award that
is not intended to be Performance-Based Compensation.
 
     2.2.  Determination of Cash Incentive Awards.  Each Cash Incentive Award
that is intended to be Performance-Based Compensation shall be determined in
accordance with the following:
 
          (a) The Cash Incentive Award for each Participant for any Performance
     Period shall equal 0.75% of the Company's Total Gross Income Less Total
     Ownership Costs (as defined in Section 8) for the Performance Period.
 
          (b) At any time prior to the payment of a Cash Incentive Award, the
     Committee may, in its discretion, reduce the amount of such award based on
     such factors as the Committee determines appropriate.
 
          (c) No payment shall be made of any Cash Incentive Award that is
     intended to be Performance-Based Compensation until achievement of the
     applicable performance objectives set forth in paragraph (a) above has been
     certified by the Committee.
 
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     Any Cash Incentive Awards that are not intended to be Performance-Based
Compensation may be conditioned on any performance goals, factors, or criteria
as the Committee shall determine.
 
                                   SECTION 3
 
                                 DISTRIBUTIONS
 
     Subject to subsection 2.2, a Participant's Cash Incentive Award shall be
distributed to the Participant in cash at such time and in such form as is
determined by the Committee.
 
                                   SECTION 4
 
                          OPERATION AND ADMINISTRATION
 
     4.1.  Effective Date.  Subject to the approval of the stockholders of the
Company at the Company's 2004 annual meeting of its stockholders, the Plan shall
be effective as of January 1, 2004 (the "Effective Date"); provided, however,
that to the extent that Cash Incentive Awards are granted under the Plan prior
to its approval by stockholders, the Cash Incentive Awards shall be contingent
on approval of the Plan by the stockholders of the Company at such annual
meeting.
 
     4.2.  Tax Withholding.  All distributions under the Plan are subject to
withholding of all applicable taxes, and the Committee may condition the
delivery of any benefits under the Plan on satisfaction of the applicable
withholding obligations.
 
     4.3.  Transferability.  Except as otherwise provided by the Committee, Cash
Incentive Awards under the Plan are not transferable except as designated by the
Participant by will or by the laws of descent and distribution.
 
     4.4.  Heirs and Successors.  The Plan shall be binding upon, and inure to
the benefit of, the Company and its successors and assigns, and upon any person
acquiring, whether by merger, consolidation, purchase of assets or otherwise,
all or substantially all of the Company's assets and business. If any benefits
deliverable to a Participant under the Plan have not been delivered at the time
of the Participant's death, such benefits shall be delivered to the Designated
Beneficiary in accordance with the provisions of the Plan. The "Designated
Beneficiary" shall be the beneficiary or beneficiaries designated by a
Participant in a writing filed with the Committee in such form and at such time
as the Committee shall require. If a deceased Participant fails to designate a
beneficiary, or if the Designated Beneficiary does not survive the Participant,
any benefits distributable to the Participant shall be distributed to the legal
representative of the estate of the Participant. If a deceased Participant
designates a beneficiary and the Designated Beneficiary survives the Participant
but dies before the complete distribution of benefits to the Designated
Beneficiary under the Plan, then any benefits distributable to the Designated
Beneficiary shall be distributed to the legal representative of the estate of
the Designated Beneficiary.
 
     4.5.  Agreement With Company.  A Cash Incentive Award under the Plan may be
subject to such terms and conditions, not inconsistent with the Plan, as the
Committee shall, in its sole discretion, prescribe. The terms and conditions of
any Cash Incentive Award to any Participant may be reflected in such form of
written document as is determined by the Committee. A copy of such document
shall be provided to the Participant, and the Committee may, but need not
require that the Participant sign a copy of such document. Such document is
referred to in the Plan as an "Award Agreement" regardless of whether any
Participant signature is required.
 
     4.6.  Action by Company or Subsidiary.  Any action required or permitted to
be taken by the Company or any Subsidiary shall be by resolution of its board of
directors, or by action of one or more members of the board (including a
committee of the board) who are duly authorized to act for the board, or (except
to the extent prohibited by applicable law or applicable rules of any stock
exchange) by a duly authorized officer of such company.
 
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     4.7.  Gender and Number.  Where the context admits, words in any gender
shall include any other gender, words in the singular shall include the plural
and the plural shall include the singular.
 
     4.8.  Limitation of Implied Rights.
 
          (a) Neither a Participant nor any other person shall, by reason of
     participation in the Plan, acquire any right in or title to any assets,
     funds or property of the Company or any Subsidiary whatsoever, including,
     without limitation, any specific funds, assets, or other property which the
     Company or any Subsidiary, in its sole discretion, may set aside in
     anticipation of a liability under the Plan. A Participant shall have only a
     contractual right to the amounts, if any, payable under the Plan, unsecured
     by any assets of the Company or any Subsidiary, and nothing contained in
     the Plan shall constitute a guarantee that the assets of the Company or any
     Subsidiary shall be sufficient to pay any benefits to any person.
 
          (b) The Plan does not constitute a contract of employment, and
     selection as a Participant will not give any participating employee or
     other individual the right to be retained in the employ of the Company or
     any Subsidiary or the right to continue to provide services to the Company
     or any Subsidiary, nor any right or claim to any benefit under the Plan,
     unless such right or claim has specifically accrued under the terms of the
     Plan.
 
     4.9.  Evidence.  Evidence required of anyone under the Plan may be by
certificate, affidavit, document or other information which the person acting on
it considers pertinent and reliable, and signed, made or presented by the proper
party or parties.
 
                                   SECTION 5
 
                        SOURCE OF BENEFIT DISTRIBUTIONS
 
     An Employer shall be liable for distribution of benefits under the Plan
with respect to any Participant to the extent that such benefits are
attributable to services rendered by the Participant to that Employer. Any
disputes relating to liability of Employers for benefit distributions shall be
resolved by the Committee.
 
                                   SECTION 6
 
                                   COMMITTEE
 
     6.1.  Administration.  The authority to control and manage the operation
and administration of the Plan shall be vested in the Compensation Committee of
the Board (the "Committee") in accordance with this Section 6, Section 303A.05
of the NYSE Listed Company Manual and section 162(m) of the Code. The Committee
shall consist solely of three members of the Board who are not employees of the
Company or any Subsidiary. If the Committee does not exist, or for any other
reason determined by the Board, the Board may take any action under the Plan
that would otherwise be the responsibility of the Committee.
 
     6.2.  Powers of Committee.  The Committee's administration of the Plan
shall be subject to the following:
 
          (a) Subject to the provisions of the Plan, the Committee will have the
     authority and discretion to select from among the Eligible Employees those
     persons who shall be eligible to participate in the Plan.
 
          (b) The Committee will have the authority and discretion to interpret
     the Plan, to establish, amend, and rescind any rules and regulations
     relating to the Plan, and to make all other determinations that may be
     necessary or advisable for the administration of the Plan.
 
          (c) Any interpretation of the Plan by the Committee and any decision
     made by it under the Plan is final and binding on all persons.
 
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     6.3.  Delegation by Committee.  Except to the extent prohibited by
applicable law, the Committee may allocate all or any portion of its
responsibilities and powers to any one or more of its members and may delegate
all or any part of its responsibilities and powers to any person or persons
selected by it. Any such allocation or delegation may be revoked by the
Committee at any time.
 
     6.4.  Information to be Furnished to Committee.  The Company and
Subsidiaries shall furnish the Committee with such data and information as it
determines may be required for it to discharge its duties. The records of the
Company and Subsidiaries as to an employee's or Participant's employment,
termination of employment, leave of absence, reemployment and compensation shall
be conclusive on all persons unless determined to be incorrect. Participants and
other persons entitled to benefits under the Plan must furnish the Committee
such evidence, data or information as the Committee considers desirable to carry
out the terms of the Plan.
 
                                   SECTION 7
 
                           AMENDMENT AND TERMINATION
 
     The Board may, at any time, amend or terminate the Plan, provided that no
amendment or termination may, in the absence of written consent to the change by
the affected Participant (or, if the Participant is not then living, the
affected beneficiary), adversely affect the rights of any Participant or
beneficiary under any Cash Incentive Award granted under the Plan prior to the
date such amendment is adopted by the Board.
 
                                   SECTION 8
 
                                 DEFINED TERMS
 
     In addition to the other definitions contained herein, the following
definitions shall apply:
 
          (a) Board.  The term "Board" means the Board of Directors of the
     Company.
 
          (b) Cash Incentive Award.  The term "Cash Incentive Award" means an
     award determined in accordance with Section 2 and distributable in
     accordance with Section 3.
 
          (c) Code.  The term "Code" means the Internal Revenue Code of 1986, as
     amended. A reference to any provision of the Code shall include reference
     to any successor provision of the Code.
 
          (d) Eligible Employee.  The term "Eligible Employee" means any key
     employee of the Company or a Subsidiary.
 
          (e) Employer.  The term "Employer" means the Company and each of the
     Subsidiaries whose employees the Committee includes in the Plan as
     Participants.
 
          (f) Participant.  The term "Participant" means an individual who has
     been designated by the Committee as eligible to participate in the Plan.
 
          (g) Performance-Based Compensation.  The term "Performance-Based
     Compensation" shall have the meaning ascribed to it in section 162(m) of
     the Code and the regulations thereunder.
 
          (h) Performance Period.  The term "Performance Period" shall mean the
     Company's fiscal year, or such other period as may be established by the
     Committee from time to time as the Performance Period.
 
          (i) Subsidiary.  The term "Subsidiary" means any company during any
     period in which it is a "subsidiary corporation" (as that term is defined
     in Code section 424(f)) with respect to the Company, and any other business
     venture designated by the Committee in which the
 
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     Company (or any entity that is a successor to the Company) has a
     significant interest, as determined in the discretion of the Committee.
 
          (j) Total Gross Income Less Total Ownership Costs.  The term "Total
     Gross Income Less Total Ownership Costs" means the Company's "Total Gross
     Income" less "Total Ownership Costs" as reported in the Company's
     consolidated statement of income (or if such amounts are not reported in
     the Company's statement of income, the line items in the Company's
     statement of income determined by the Committee to correspond thereto).
 
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