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                                                                       EXHIBIT 8

                       NEAL, GERBER & EISENBERG LETTERHEAD



                                  May 17, 2000

Union Tank Car Company
225 West Washington Street
Chicago, Illinois  60606

         Re:   Pass Through Certificates

Ladies and Gentlemen:

         We have acted as counsel to you in connection with the filing by Union
Tank Car Company, a Delaware corporation (the "Company"), of its Registration
Statement on Form S-3 (the "Registration Statement") under the Securities Act of
1933, which Registration Statement, together with a registration statement
previously filed by the Company (Registration No. 333-45105), relates to up to
$302,148,000 in aggregate principal amount of Pass Through Certificates of the
Company (the "Certificates"). The Certificates will be issued pursuant to the
terms of the Pass Through Trust Agreement dated as of May 17, 2000, to be
entered into between the Company and Bank One, National Association, as Pass
Through Trustee (the "Pass Through Trustee"), the form of which has been filed
as an exhibit to the Registration Statement (the "Pass Through Trust
Agreement"), as it may be supplemented from time to time by a separate
supplement for each series of Certificates (each, a "Supplement").

         As such counsel, we have examined the proposed form of the Pass Through
Trust Agreement and such other papers, documents and certificates of public
officials and certificates of officers of the Company as we have deemed relevant
and necessary as a basis for the opinions hereinafter expressed. In such
examinations, we have assumed the genuineness of all signatures and the
authenticity of all documents submitted to us as originals and the conformity to
original documents of all documents submitted to us as conformed or photostatic
copies. We have also assumed that the Pass Through Trust Agreement will, when
executed and delivered, be substantially in the form submitted to us for
examination. As to any facts material to our opinion, we have relied upon
statements, certificates and representations and warranties of the Company, and
its officers, including representations and warranties contained in the Pass
Through Trust Agreement.

         We hereby confirm to you our opinion(s) as set forth under the headings
"Certain United States Federal Income Tax Consequences" and "Certain Illinois
Taxes" in the Prospectus relating to the Certificates included in the
Registration Statement.


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         We are members of the Bar of the State of Illinois, and we express no
opinion herein concerning any laws other than the law of the State of Illinois
and the Federal law of the United States of America.

         We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to our firm under the captions
"Certain United States Federal Income Tax Consequences" and "Certain Illinois
Taxes" in the prospectus relating to the Certificates that constitutes a part of
the Registration Statement.

                                           Very truly yours,

                                           /s/ Neal, Gerber & Eisenberg

                                           NEAL, GERBER & EISENBERG