UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d)

OF THE SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported)

August 6, 2015 (August 4, 2015)

QUALITY DISTRIBUTION, INC.

(Exact name of registrant as specified in its charter)

4041 Park Oaks Boulevard, Suite 200

Tampa, Florida 33610

(Address of principal executive offices including Zip Code)

(813) 630-5826

(Registrant’s telephone number, including area code)

N.A.

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

As previously reported, on May 6, 2015, Quality Distribution, Inc. (“Quality” or the “Company”) entered into an Agreement and Plan of Merger with Gruden Acquisition, Inc. (“Parent”) and Gruden Merger Sub, Inc. (“Merger Sub”) pursuant to which Merger Sub will merge with and into the Company. Parent and Merger Sub are entities formed by funds advised by Apax Partners LLP. On August 4, 2015 the Company received notice from the Committee on Foreign Investment in the United States (“CFIUS”) that CFIUS has concluded its review of the transaction and determined that there are no unresolved national security concerns with respect to the transaction.

Forward-Looking Statements

This Form 8-K contains, and other written or oral statements made by or on behalf of the Company may include, forward-looking statements, within the meaning of the Private Securities Litigation Reform Act of 1995. In addition, we or our executive officers on our behalf, may from time to time make forward-looking statements in reports and other documents that are filed with the Securities and Exchange Commission (SEC) or in connection with oral statements made to the press, potential investors or others. Specifically, forward-looking statements may include, but are not limited to, statements relating to our future economic performance, business prospects, revenue, income, and financial condition; and statements preceded by, followed by, or that include the words “expects,” “believes,” “intends,” “will,” “anticipates,” and similar terms that relate to future events, performance, or our results. Examples of forward-looking statements include, but are not limited to, statements about the price, terms and closing date of the proposed transaction and statements regarding shareholder and regulatory approvals. Forward-looking statements are subject to certain risks and uncertainties that could cause actual results, expectations, or outcomes to differ materially from our historical experience as well as management’s present expectations or projections. These risks and uncertainties include, but are not limited to: (i) the occurrence of any event, change or other circumstances that could give rise to the termination of the merger agreement; (ii) the inability to complete the proposed merger due to the failure to obtain the Company Requisite Vote or the failure to satisfy other conditions of the proposed merger within the proposed timeframe or at all; (iii) the failure to obtain the necessary financing arrangements as set forth in the debt and equity commitment letters delivered pursuant to the merger agreement, or the failure of the proposed merger to close for any other reason; (iv) risks related to disruption of management’s attention from the Company’s ongoing business operations due to the transaction; (v) the outcome of any legal proceedings, regulatory proceedings or enforcement matters that may be instituted against the Company and others relating to the merger agreement; (vi) the risk that the pendency of the proposed merger disrupts current plans and operations and the potential difficulties in employee retention as a result of the pendency of the proposed merger; (vii) the effect of the announcement of the proposed merger on the Company’s relationships with its customers, operating results and business generally; and (viii) the amount of the costs, fees, expenses and charges related to the proposed merger. Consider these factors carefully in evaluating the forward-looking statements. Additional factors that may cause results to differ materially from those described in the forward-looking statements are set forth in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2014, which was filed with the SEC on March 13, 2015. The forward-looking statements represent the Company’s views as of the date on which such statements were made and the Company undertakes no obligation to publicly update such forward-looking statements.

Participants in the Solicitation

The Company and its directors, executive officers and certain other members of management and employees of the Company may be deemed to be “participants” in the solicitation of proxies from the shareholders of the Company in connection with the proposed merger. Information regarding the interests of the persons who may, under the rules of the SEC, be considered participants in the solicitation of the shareholders of the Company in connection with the proposed merger, which may be different than those of the Company’s shareholders generally, are set forth in the definitive proxy statement and the other relevant documents filed with the SEC. Shareholders can find information about the Company and its directors and executive officers and their ownership of the Company’s common stock in the Company’s annual report on Form 10-K for the fiscal year ended December 31, 2014 and in its definitive proxy

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statement relating to its special shareholders meeting filed with the SEC on July 16, 2015. These documents may be obtained free of charge from the SEC’s website at www.sec.gov and the Company’s website at https://www.qualitydistribution.com/.

Important Additional Information and Where to Find It

This Form 8-K may be deemed to be solicitation material in respect of the proposed acquisition of the Company by Parent, an entity formed by funds advised by Apax Partners LLP pursuant to the previously announced merger. In connection with the proposed merger, the Company filed with the SEC on July 16, 2015, and mailed to its shareholders on July 17, 2015, a definitive proxy statement and other relevant documents. QUALITY SHAREHOLDERS ARE ADVISED TO READ THE DEFINITIVE PROXY STATEMENT (INCLUDING ALL AMENDMENTS AND SUPPLEMENTS THERETO) BECAUSE IT CONTAINS IMPORTANT INFORMATION. Investors may obtain a free copy of the definitive proxy statement and other relevant documents filed by the Company with the SEC at the SEC’s Web site at http://www.sec.gov. The definitive proxy statement and such other documents filed by the Company with the SEC may also be obtained for free from the Investor Relations section of the Company’s web site (https://www.qualitydistribution.com/) or by directing a request to: Quality Distribution, Inc., 4041 Park Oaks Blvd., Suite 200, Tampa, FL 33610, Attention: Investor Relations.

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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 hereunto duly authorized.

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