<PAGE>

                                   Form 10-Q

                       SECURITIES AND EXCHANGE COMMISSION
                            WASHINGTON, D.C.  20549


                QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d)
    [ X ]           OF THE SECURITIES EXCHANGE ACT OF 1934
               For the quarterly period ended September 30, 2000

                                       OR

               TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d)
    [   ]           OF THE SECURITIES EXCHANGE ACT OF 1934
             For the transition period from__________ to _________

                         Commission file number 1-5666
                         -----------------------------


                             UNION TANK CAR COMPANY
             (Exact name of registrant as specified in its charter)


                 Delaware                               36-3104688
                 --------                               ----------
      (State or other jurisdiction of              (I.R.S. Employer
      incorporation or organization)             Identification Number)


              225 West Washington Street, Chicago, Illinois 60606
              ---------------------------------------------------
                    (Address of principal executive offices)

      Registrant's telephone number, including area code:  (312) 372-9500

Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                          Yes    X      No
                              -------      -------

There is no voting stock held by non-affiliates of the registrant. This report
is being filed by the registrant as a result of undertakings made pursuant to
Section 15(d) of the Securities Exchange Act of 1934.

Included in this filing are 11 pages, sequentially numbered in the bottom center
of each page.

                                      -1-
<PAGE>

                    UNION TANK CAR COMPANY AND SUBSIDIARIES
                                   FORM 10-Q
                                     INDEX

<TABLE>
<CAPTION>
                                                                                         Page
                                                                                         ----
<S>       <C>                                                                            <C>
Part I.   Financial Information

          Item 1.   Financial Statements

                    Condensed consolidated statement of income -
                      three and nine month periods ended
                      September 30, 2000 and 1999 (Restated)                                3

                    Condensed consolidated balance sheet -
                      September 30, 2000 and December 31, 1999 (Restated)                   4

                    Condensed consolidated statement of cash flows -
                      nine months ended September 30, 2000 and 1999 (Restated)              5

                    Notes to condensed consolidated financial statements                6 - 8

          Item 2.   Management's Discussion and Analysis
                       of Financial Condition and Results of Operations                     9

          Item 3.   Quantitative and Qualitative Disclosures About Market Risk             10


Part II.  Other Information

          Item 1.   Legal Proceedings                                                      10

          Item 6.   Exhibits and Reports on Form 8-K                                       10

Signatures                                                                                 11
</TABLE>

                                      -2-
<PAGE>

                        PART I.    FINANCIAL INFORMATION


ITEM 1.  FINANCIAL STATEMENTS

                    UNION TANK CAR COMPANY AND SUBSIDIARIES
                   CONDENSED CONSOLIDATED STATEMENT OF INCOME
                             (Dollars in Thousands)
                                  (Unaudited)
<TABLE>
<CAPTION>
                                              Three Months Ended                  Nine Months Ended
                                                September 30,                       September 30,
                                          -------------------------         -----------------------------
                                            2000             1999              2000               1999
                                          --------         --------         ----------         ----------
                                                          (Restated)                           (Restated)
<S>                                       <C>              <C>              <C>                <C>
Revenues
   Services (leasing and other)           $168,498         $158,210         $  494,644         $  471,375
   Net sales                               187,591          195,620            585,918            598,755
                                          --------         --------         ----------         ----------
                                           356,089          353,830          1,080,562          1,070,130
Other income                                11,374            7,549             27,252             20,445
                                          --------         --------         ----------         ----------
                                           367,463          361,379          1,107,814          1,090,575
Costs and expenses
   Cost of services                        102,391           93,234            294,519            276,495
   Cost of sales                           154,534          166,539            485,774            506,526
   General and administrative               36,551           33,101            101,264             98,581
   Interest                                 19,302           19,088             55,613             54,523
                                          --------         --------         ----------         ----------
                                           312,778          311,962            937,170            936,125
                                          --------         --------         ----------         ----------
Income before income taxes                  54,685           49,417            170,644            154,450

Provision for income taxes
   Current                                  17,059           12,043             58,294             44,534
   Deferred                                    255            6,756              4,127             16,023
                                          --------         --------         ----------         ----------
                                            17,314           18,799             62,421             60,557
                                          --------         --------         ----------         ----------
Net income                                $ 37,371         $ 30,618         $  108,223         $   93,893
                                          ========         ========         ==========         ==========
</TABLE>



           See notes to condensed consolidated financial statements.

                                      -3-
<PAGE>

                    UNION TANK CAR COMPANY AND SUBSIDIARIES
                      CONDENSED CONSOLIDATED BALANCE SHEET
                             (Dollars in Thousands)
                                  (Unaudited)


<TABLE>
<CAPTION>
                                                                   September 30,            December 31,
                                                                       2000                    1999
                                                                ------------------      -------------------
                                                                                             (Restated)
<S>                                                               <C>                     <C>
Assets
------

Cash and cash equivalents                                           $   69,331              $   50,936
Accounts receivable, primarily trade due within one year               156,512                 131,350
Accounts and notes receivable, affiliates                               57,320                   9,202
Inventories, net of LIFO of $34,099
    ($33,481 at December 31, 1999)                                     178,306                 162,218
Prepaid expenses and deferred charges                                   16,407                   9,796
Advances to parent company,
    principally at LIBOR plus 1%                                       255,101                 266,722
Railcar lease fleet, net                                             1,556,428               1,653,495
Fixed assets, net                                                      491,673                 229,372
Investment in aircraft direct financing lease                           31,130                  34,012
Other assets                                                            79,263                  78,973
                                                                    ----------              ----------
      Total assets                                                  $2,891,471              $2,626,076
                                                                    ==========              ==========


Liabilities, Deferred Items and Stockholder's Equity
----------------------------------------------------

Accounts payable                                                    $   72,912              $   74,891
Accrued liabilities, including minority interest                       324,673                 267,825
Borrowed debt, including $73,893 due within
    one year ($44,276 at December 31, 1999)                          1,125,911                 986,240
                                                                    ----------              ----------
                                                                     1,523,496               1,328,956


Deferred income taxes and investment tax credits                       459,029                 457,991


Stockholder's equity
  Common stock and additional capital                                  240,148                 203,554
  Retained earnings                                                    668,798                 635,575
                                                                    ----------              ----------
    Total stockholder's equity                                         908,946                 839,129
                                                                    ----------              ----------
      Total liabilities, deferred items and
               stockholder's equity                                 $2,891,471              $2,626,076
                                                                    ==========              ==========
</TABLE>

           See notes to condensed consolidated financial statements.

                                      -4-
<PAGE>

                    UNION TANK CAR COMPANY AND SUBSIDIARIES
                 CONDENSED CONSOLIDATED STATEMENT OF CASH FLOWS
                             (Dollars in Thousands)
                                  (Unaudited)
<TABLE>
<CAPTION>
                                                                               Nine Months Ended
                                                                                 September 30,
                                                                        ------------------------------
                                                                          2000                 1999
                                                                        ---------            ---------
                                                                                             (Restated)
<S>                                                                     <C>                  <C>
Cash flows from operating activities:
  Net income                                                            $ 108,223            $  93,893
  Adjustments to reconcile net income to net cash
    provided by operating activities:
       Depreciation and amortization                                      115,029              109,627
       Deferred taxes                                                       4,127               16,023
       Gain on disposition of railcars and other fixed assets              (3,913)              (5,164)
       Other non-cash income and expenses                                   3,470                2,530
       Changes in assets and liabilities:
         Accounts receivable                                              (15,516)             (18,621)
         Inventories                                                      (20,588)              19,660
         Prepaid expenses and deferred charges                             (4,603)                 727
         Accounts payable and accrued expenses                            (22,416)             (20,787)
                                                                        ---------            ---------
Net cash provided by operating activities                                 163,813              197,888

Cash flows from investing activities:
  Construction and purchase of railcars and other fixed assets           (158,570)            (158,849)
  Decrease (Increase) in advance to parent                                 57,318             (117,574)
  Increase in other assets                                                 (4,398)                (512)
  Purchases of businesses, net of cash acquired                          (263,700)             (11,764)
  Proceeds from disposals of railcars and other fixed assets                9,523               10,232
                                                                        ---------            ---------
Net cash used in investing activities                                    (359,827)            (278,467)

Cash flows from financing activities:
  Proceeds from issuance of borrowed debt                                 183,576              175,000
  Proceeds from sale-leaseback transactions                               150,026               13,200
  Principal payments of borrowed debt                                     (42,363)             (44,846)
  Cash dividends                                                          (75,000)             (59,000)
                                                                        ---------            ---------
Net cash provided by financing activties                                  216,239               84,354

Effect of exchange rates on cash and cash equivalents                      (1,830)               2,306
                                                                        ---------            ---------
Net increase in cash and cash equivalents                                  18,395                6,081

Cash and cash equivalents at beginning of year                             50,936               62,367
                                                                        ---------            ---------
Cash and cash equivalents at end of period                              $  69,331            $  68,448
                                                                        =========            =========
Cash paid during the period for:
  Interest (net of amount capitalized)                                  $  60,469            $  57,068
  Income taxes                                                             56,880               50,641
</TABLE>

           See notes to condensed consolidated financial statements.

                                      -5-
<PAGE>

                    UNION TANK CAR COMPANY AND SUBSIDIARIES
             NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
                            (Dollars in Thousands)
                                  (Unaudited)

1.   UNION TANK CAR COMPANY (the "Company") is a wholly-owned subsidiary of
     Marmon Industrial LLC ("Marmon Industrial"). Marmon Industrial is a wholly-
     owned subsidiary of Marmon Holdings, Inc. ("Marmon Holdings"),
     substantially all of the stock of which is owned, directly or indirectly,
     by trusts for the benefit of certain members of the Pritzker family. As
     used herein, "Pritzker family" refers to the lineal descendants of Nicholas
     J. Pritzker, deceased.

2.   The accompanying unaudited condensed consolidated financial statements
     include all adjustments, consisting of normal recurring accruals, which the
     Company considers necessary for a fair presentation. These interim
     financial statements do not include all disclosures normally provided in
     annual financial statements. Accordingly, they should be read in
     conjunction with the consolidated financial statements and notes thereto in
     the Company's 1999 Annual Report on Form 10-K.

     On September 1, 2000, the Company acquired Marmon/Keystone Corporation, a
     company under common control, through a capital contribution from Marmon
     Holdings. Marmon/Keystone Corporation is a leading distributor of carbon
     steel, stainless steel, aluminum and nickel tubular products among other
     products. The acquisition has been accounted for on an "as if pooled" basis
     and, accordingly, the accompanying financial statements include the
     financial positions, results of operations, and cash flows of the combined
     companies for all periods presented.

     Certain prior year amounts have been reclassified to conform to the current
     year presentation.

     The 2000 interim results presented herein are not necessarily indicative of
     the results of operations for the full year 2000.


3.   As more fully described in the Company's 1999 Annual Report on Form 10-K,
     under an arrangement with Marmon Industrial, the Company is included in the
     consolidated federal income tax return of Marmon Holdings. As a member of a
     consolidated federal income tax group, the Company is contingently liable
     for the federal income taxes of the other members of the group.

4.   The Company and its subsidiaries have been named as defendants in a number
     of lawsuits, and certain claims are pending. The Company has accrued what
     it reasonably expects to pay in resolution of these matters and, in the
     opinion of management, their ultimate resolution will not have a material
     effect on the Company's consolidated financial position or results of
     operations.

5.   Foreign currency translation adjustments and transaction gains and losses
     are assumed by the Company's parent. For the nine months ended September
     30, 2000 and 1999, Marmon Industrial absorbed a gain of $1,097 and a loss
     of $470, respectively.

                                      -6-
<PAGE>

6.   The Company's foreign subsidiaries periodically enter into foreign currency
     forward contracts to hedge against U.S. dollar exposures. Foreign currency
     forward contracts, all with initial maturities of less than one year,
     amounted to $8,700 at September 30, 2000 and $9,100 at December 31, 1999.

7.   In September 2000, EXSIF Worldwide, Inc. ("EWI"), an indirect majority-
     owned subsidiary of the Company, purchased the intermodal tank container
     leasing business of Transamerica Leasing, Inc., for approximately $264,000.
     In addition to the purchase price paid for the assets acquired, EWI assumed
     the seller's operating leases with its customers, agreements under which
     the seller managed equipment for or leased equipment from third parties,
     and certain of the seller's operating liabilities. The acquisition has been
     accounted for using the purchase method and the Company is in the process
     of finalizing the purchase price allocation to the assets acquired and
     liabilities assumed. No pro forma information is disclosed as the
     acquisition is below the required threshold for such disclosure.

     In September 2000, EWI issued $180,000 principal amount of Senior Secured
     Notes to finance a portion of the purchase price of the acquisition.
     Interest on the notes is payable semiannually on April 1 and October 1,
     commencing April 1, 2001 at the rate of 7.68% per annum. Principal is
     payable annually commencing on October 1, 2001 and continuing until
     maturity on October 1, 2015. The notes are secured by tank container assets
     with a total purchase price of approximately $240,000. Payment of the notes
     has been guaranteed by the Company.

     In September 2000, Worldwide Containers, Inc. ("WCI"), a majority-owned
     subsidiary of the Company, received a capital contribution from an
     affiliate consisting of a $43,400 demand note of an affiliate of the
     Company and 20% of the capital stock of Webb Wheel Products, Inc., another
     affiliate of the Company, in exchange for approximately 15.1% of the
     capital stock of WCI. WCI also received a capital contribution from an
     affiliate consisting of a 20% limited partnership interest in Rail Car
     Associates Limited Partnership from an affiliate in exchange for
     approximately 4.2% of the capital stock of the WCI. These noncash
     transactions have been excluded from the consolidated statement of cash
     flows.

8.   Segment Information

<TABLE>
<CAPTION>
                                                             Metal Pipe
                                                               & Tube              Consolidated
                                                   Railcar  Distribution All Other    Totals
                                                   -------  ------------ --------- -----------
                                                                (Dollars in Millions)
<S>                                                  <C>        <C>       <C>        <C>
Three months ended September 30, 2000
-------------------------------------
Revenues from external customers                   $168.7      $122.9     $ 64.5     $  356.1
Income before income taxes                           40.7         3.6       10.4         54.7

Three months ended September 30, 1999 (Restated)
------------------------------------------------
Revenues from external customers                   $191.2      $113.9      $ 48.7     $  353.8
Income before income taxes                           38.6         6.1         4.7         49.4

Nine months ended September 30, 2000
------------------------------------
Revenues from external customers                   $534.3      $376.7      $169.6     $1,080.6
Income before income taxes                          131.1        16.9        22.6        170.6

Nine months ended September 30, 1999 (Restated)
-----------------------------------------------
Revenues from external customers                   $574.6      $346.3      $149.2     $1,070.1
Income before income taxes                          119.8        18.0        16.7        154.5
</TABLE>

                                      -7-
<PAGE>

9.  Condensed Consolidating Financial Information (dollars in millions):

<TABLE>
<CAPTION>
                                                         Union
                                                        Tank Car     Procor         Other
                                                        Company      Limited     Subsidiaries   Eliminations   Consolidated
                                                        --------     -------     ------------   ------------   ------------
September 30, 2000
------------------
Assets
------
<S>                                                     <C>           <C>          <C>           <C>           <C>
Investment in and advances to subsidiaries              $  871.9      $   --       $  266.1      $(1,138.0)      $     --
Long-lived assets                                        1,308.1       210.0          640.5           (0.1)       2,158.5
Other assets                                               179.6       127.7          427.5           (1.8)         733.0
                                                        --------      ------       --------      ---------       --------
                                                        $2,359.6      $337.7       $1,334.1      $(1,139.9)      $2,891.5
                                                        ========      ======       ========      =========       ========
<CAPTION>
Liabilities, Deferred Items and Stockholder's Equity
----------------------------------------------------
<S>                                                     <C>           <C>          <C>           <C>           <C>
Total liabilities                                       $1,081.5      $113.1       $  295.7      $    33.2       $1,523.5
Deferred income taxes                                      361.4        74.2           23.4            0.0          459.0
Stockholder's equity                                       916.7       150.4        1,015.0       (1,173.1)         909.0
                                                        --------      ------       --------      ---------       --------
                                                        $2,359.6      $337.7       $1,334.1      $(1,139.9)      $2,891.5
                                                        ========      ======       ========      =========       ========
<CAPTION>
December 31, 1999 (Restated)
----------------------------
Assets
------
<S>                                                     <C>           <C>          <C>           <C>           <C>
Investment in and advances to subsidiaries              $  472.0      $   --       $  116.7      $  (588.7)      $     --
Long-lived assets                                        1,567.1       229.6          199.2             --        1,995.9
Other assets                                               251.5       114.9          265.3           (1.5)         630.2
                                                        --------      ------       --------      ---------       --------
                                                        $2,290.6      $344.5       $  581.2      $  (590.2)      $2,626.1
                                                        ========      ======       ========      =========       ========
<CAPTION>
Liabilities, Deferred Items and Stockholder's Equity
----------------------------------------------------
<S>                                                     <C>           <C>          <C>           <C>           <C>
Total liabilities                                       $1,113.2      $112.2       $  128.0      $   (24.4)      $1,329.0
Deferred income taxes                                      414.0        78.4          (34.6)           0.2          458.0
Stockholder's equity                                       763.4       153.9          487.8         (566.0)         839.1
                                                        --------      ------       --------      ---------       --------
                                                        $2,290.6      $344.5       $  581.2      $  (590.2)      $2,626.1
                                                        ========      ======       ========      =========       ========
<CAPTION>
Three Months Ended September 30, 2000
-------------------------------------
<S>                                                     <C>           <C>          <C>           <C>           <C>
Total Revenues                                          $  139.8      $ 24.7       $  206.5      $   (14.9)      $  356.1
Total Costs and Expenses                                   106.9        19.6          187.9           (1.6)         312.8
Net Income                                                  21.5         7.9            8.0            0.0           37.4

<CAPTION>
Three Months Ended September 30, 1999 (Restated)
------------------------------------------------
<S>                                                     <C>           <C>          <C>           <C>           <C>
Total Revenues                                          $  167.2      $ 27.8       $  172.1      $   (13.3)      $  353.8
Total Costs and Expenses                                   137.5        22.6          159.6           (7.7)         312.0
Net Income                                                  18.9         3.8            7.5            0.4           30.6

<CAPTION>
Nine Months Ended September 30, 2000
------------------------------------
<S>                                                     <C>           <C>          <C>           <C>           <C>
Total Revenues                                          $  450.8      $ 82.1       $  585.4      $   (37.7)      $1,080.6
Total Costs and Expenses                                   350.7        61.8          550.2          (25.5)         937.2
Net Income                                                  65.0        19.4           23.2            0.6          108.2

<CAPTION>
Nine Months Ended September 30, 1999 (Restated)
-----------------------------------------------
<S>                                                     <C>           <C>          <C>           <C>           <C>
Total Revenues                                          $  502.8      $ 87.3       $  521.3      $   (41.3)      $1,070.1
Total Costs and Expenses                                   411.5        71.7          490.1          (37.2)         936.1
Net Income                                                  54.9        10.9           26.8            1.3           93.9
</TABLE>

                                       -8-
<PAGE>

ITEM 2.  MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION
         AND RESULTS OF OPERATIONS

Results of Operations
---------------------
3rd Quarter 2000 versus 1999
----------------------------
Service revenues increased $10.3 million primarily due to the effects of
railcars added to the lease fleet ($3.7 million) and the intermodal tank
container operations ($5.5 million) acquired in September 2000.

Sales revenues decreased $8.0 million primarily due to reduced sales of railcars
($31.2 million) offset by increased sulphur service processing plant sales
($11.4 million) and increased sales of metal pipe and tubing products ($9.0
million).

Income taxes decreased due to an enacted change in the Canadian tax rates and
its impact on deferred taxes.


Nine Months 2000 versus 1999
----------------------------
Service revenues increased $23.3 million primarily due to the effects of
railcars added to the lease fleet ($9.2 million) and the intermodal tank
container operations ($5.5 million) acquired in September 2000. The remaining
increase came from contract switching services operations ($2.3 million) and
sulphur service processing operations ($3.6 million).

Sales revenues decreased $12.8 million primarily due to reduced sales of
railcars ($56.1 million) offset by increased sulphur service processing plant
sales ($11.2 million) and increased sales of metal pipe and tubing products
($29.6 million).


Financial Condition
-------------------
2000 versus 1999
----------------

Operating activities provided $163.8 million of cash in the first nine months of
2000. These funds, along with the proceeds from the issuance of debt and sale-
leaseback transactions, were used to provide for railcar additions, pay
dividends to the Company's stockholder, service borrowed debt obligations, and
fund an acquisition.

Management expects future cash to be provided from operating activities, long-
term financings and collection of funds previously advanced to parent will be
adequate to provide for continued expansion of the Company's business and enable
it to meet its debt service obligations.

                                      -9-
<PAGE>

ITEM 3.  QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

At September 30, 2000, there has been no significant change to the Company's
exposure to market risk since December 31, 1999.


                          PART II.  OTHER INFORMATION


Item 1.   Legal Proceedings

          Reference is made to "Business - Environmental Matters" in the
          Company's Annual Report on Form 10-K for the year ended December 31,
          1999 for a description of certain environmental matters.

Item 6.   Exhibits and Reports on Form 8-K

     b.   No report on Form 8-K was filed during the quarter ended September 30,
          2000.

                                      -10-
<PAGE>

                                   SIGNATURES



Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.



                                      UNION TANK CAR COMPANY

                                      REGISTRANT



Dated:  November 14, 2000             /s/ R.C. Gluth
                                      ---------------------------------
                                          R.C. Gluth
                                      Executive Vice President,
                                        Director and Treasurer
                                        (principal financial officer
                                        and principal accounting
                                        officer)

                                      -11-