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                                                                     EXHIBIT 8.1
 
                                [LETTERHEAD OF]
 
                            CRAVATH, SWAINE & MOORE
                               [NEW YORK OFFICE]
 
              ISSUANCE OF 5 1/4% CONVERTIBLE PREFERRED SECURITIES
                            BY COLTEC CAPITAL TRUST
 
                                                                   July 13, 1998
 
Dear Sirs:
 
     We have acted as counsel for Coltec Industries Inc, a Pennsylvania
corporation (the "Company"), and Coltec Capital Trust, a Delaware business trust
(the "Trust"), in connection with the Purchase Agreement, dated April 8, 1998,
(the "Purchase Agreement"), among you, as initial purchasers, the Company and
the Trust, relating to the sale by the Trust to you of up to 3,000,000 of the
Trust's 5 1/4% Convertible Preferred Securities (liquidation preference $50 per
Convertible Preferred Security) (the "Convertible Preferred Securities"),
representing undivided beneficial interests in the assets of the Trust.
 
     The proceeds from the sale of the Convertible Preferred Securities will be
aggregated with the entire proceeds from the sale by the Trust to the Company of
the common securities of the Trust and will be used by the Trust to purchase the
5 1/4% Convertible Subordinated Deferrable Interest Debentures due 2028 (the
"Convertible Junior Subordinated Debentures") issued by the Company.
 
     In that connection you have requested our opinion regarding certain U.S.
Federal income tax consequences relating to the Convertible Preferred
Securities. In providing our opinion, we have examined (i) the Confidential
Offering Circular relating to the Convertible Preferred Securities dated April
8, 1998 (the "Offering Circular"); (ii) the Amended and Restated Declaration of
Trust of Coltec Capital Trust dated April 14, 1998; (iii) the Purchase Agreement
dated April 8, 1998; (iv) the form of Convertible Junior Subordinated Debentures
and (v) such other documents and corporate records as we have deemed necessary
or appropriate for purposes of our opinion.
 
     Our opinion is conditioned on, among other things, the initial and
continuing accuracy of the facts, information, covenants and representations set
forth in the documents referred to above and the statements and representations
made by the Company and the Trust. We have also assumed that the transactions
related to the issuance of the Convertible Preferred Securities will be
consummated in the manner contemplated by the Offering Circular. If any of the
above described assumptions are untrue for any reason or if the issuance of
Convertible Preferred Securities is consummated in a manner that is different
from the manner in which it is described in the Offering Circular, our opinions
as expressed below may be adversely affected and may not be relied upon.
 
     Based solely upon the foregoing, we are of the opinion that under current
United States Federal income tax law:
 
          (i)  The Trust will be classified as a grantor trust and not as an
     association taxable as a corporation.
 
          (ii) The Convertible Junior Subordinated Debentures should be
     classified as indebtedness of the Company.
 
     Our opinions are based on current provisions of the Code, Treasury
Regulations promulgated thereunder, published pronouncements of the Internal
Revenue Service and case law, any of which may be changed at any time with
retroactive effect. Any change in applicable laws or the facts and circumstances
surrounding the Convertible Preferred Securities, or any inaccuracy in the
statements, facts, assumptions or representations upon which we have relied, may
affect the continuing validity of our opinions as set forth herein. We assume no
responsibility to inform you of any such change or inaccuracy that may occur or
come to our attention. Except as set forth above, we express no opinion to any
party as to the tax consequences, whether Federal, state, local or
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foreign, of the issuance of the Convertible Junior Subordinated Debentures, the
Convertible Preferred Securities, or of any transactions related to or
contemplated by such issuances.
 
     We consent to the filing of this opinion as Exhibit 8.1 to the registration
statement on Form S-3 ("Registration Statement") and to the reference to our
firm name therein. In giving this consent, we do not admit that we are within
the category of persons whose consent is required under Section 7 of the
Securities Act of 1933, as amended, or the rules or regulations of the SEC
promulgated thereunder.
 
     This opinion is being provided for the benefit of the Company so that the
Company may comply with its obligations under the Federal securities laws. The
filing of this opinion as an exhibit to the Registration Statement and the
reference to such opinion and our firm therein are not intended to create
liability under applicable state law to any person other than the Company, our
client. We are furnishing this opinion in connection with the filing of the
Registration Statement with the Securities and Exchange Commission and this
opinion is not to be used, circulated, quoted or otherwise referred to for any
other purpose without our express written permission.
 
                                          Very truly yours,
 
   
                                          CRAVATH, SWAINE & MOORE
    
 
COLTEC INDUSTRIES INC
3 Coliseum Centre
2550 West Tyvola Road
Charlotte, North Carolina 28217
 
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