INDIANAPOLIS, Aug. 5, 2013 /PRNewswire/ -- Allison Transmission Holdings Inc. (NYSE: ALSN), the world's largest manufacturer of fully-automatic transmissions for medium- and heavy-duty commercial vehicles, medium- and heavy-tactical U.S. defense vehicles and hybrid-propulsion systems for transit buses, announced today a proposed secondary offering of 16,600,000 shares of its common stock by investment funds affiliated with The Carlyle Group and Onex Partners (the "Sponsors"). A group led by BofA Merrill Lynch, Citigroup and J.P. Morgan will act as the underwriters in the proposed registered public offering of those shares. In addition, the underwriters will have an option to purchase up to 2,490,000 additional shares from the Sponsors. All of the shares are being sold on a pro rata basis by the Sponsors, which are existing stockholders of Allison Transmission Holdings, Inc. ("Allison"), in accordance with their current interests. Allison's Board of Directors has authorized the company to repurchase from the underwriters up to $100 million of shares of the 16,600,000 shares of its common stock that are the subject of the offering, subject to and concurrent with the completion of the offering. Allison intends to fund the repurchase with cash on hand. (Logo: http://photos.prnewswire.com/prnh/20120702/DE33547LOGO ) Following the offering and shares repurchase, the Sponsors will continue to beneficially own an aggregate of approximately 134,097,499 shares, or approximately 73.5% in the aggregate, of Allison's outstanding common stock after giving effect to the offering and shares repurchase (or approximately 131,607,499 shares, or approximately 72.2% in the aggregate if the underwriters fully exercise their option to purchase additional shares). The total number of outstanding shares of Allison's common stock will not change as a result of the offering, but will be reduced by the number of shares repurchased by Allison. A copy of the preliminary prospectus related to the offering may be obtained, when available, from BofA Merrill Lynch, 222 Broadway, New York, NY 10038, Attn: Prospectus Department, or e-mail email@example.com; Citigroup, c/o Broadridge Financial Solutions, 1155 Long Island Avenue, Edgewood, NY 11717 (tel: 800-831-9146); and J.P. Morgan Securities LLC, Attention: Broadridge Financial Solutions, 1155 Long Island Avenue, Edgewood, NY 11717, telephone: 866-803-9204. This press release shall not constitute an offer to sell or the solicitation of an offer to buy, nor shall there be any sale of these securities in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction.