Corporate raider Carl Icahn has mounted an unsolicited bid to take control of Oshkosh Corporation, valuing the heavy-duty truck maker at roughly $3 billion.

Oshkosh, which is based in the Wisconsin city of the same name, makes tankers, fire trucks, and other vehicles for emergency services, industrial, and military clients. The company has retained Skadden, Arps, Slate, Meagher & Flom and Foley & Lardner as it evaluates the tender offer by Icahn.

Skadden M&A partners Gary Cullen in Chicago and Richard Grossman in New York are representing Oshkosh, along with Foley & Lardner corporate partners Patrick Quick and John Wilson in Milwaukee. Both firms have previously handled work for Oshkosh, including advising on the company’s $3.2 billion acquisition of JLG Industries in 2006.

Michael Grebe, who served as chairman and CEO of Foley from 1994 until his retirement from the firm in 2002, is a member of Oshkosh’s board of directors. Also sitting on the company’s board is fellow attorney Peter Hamilton, a current chief financial officer for the Brunswick Corporation and former naval officer in the office of the general counsel at the U.S. Department of Defense. Bryan Blankfield has served as general counsel of Oshkosh since 2002.

In a statement issued by Icahn, who already owns 9.5 percent of Oshkosh, the renowned activist investor urged shareholders to accept his offer. Icahn began an unsuccessful proxy contest to wrest control of the company’s board last year by seeking to force management to admit it erred in buying JLG, which makes materials for the construction sector, and whose business slumped amid the onset of the economic recession, according to The Wall Street Journal.

So far, a source familiar with the Oshkosh machinations says Icahn is relying on an in-house legal team at his holding company led by general counsel Keith Schaitkin and associate general counsel Mark DiPaolo, but that “time will tell whether more [legal] firepower” is needed.

Schaitkin took over from Marc Weitzen this year as general counsel of Icahn’s holding company, of which former Winston & Strawn partner Daniel Ninivaggi is president, according to our previous reports. In August, Ninivaggi was named to the board of Forest Laboratories after Icahn waged another proxy fight at the New York-based pharmaceutical company.

As for Oshkosh, Icahn himself might have designs on more than just changing the direction of the company. This week another truck maker, Lisle, Illinois-based Navistar International, averted a proxy fight with Icahn and announced the appointment of three new directors with his backing.

Bloomberg reports that Icahn owns nearly 15 percent of Navistar, raising the possibility of a potential merger with Oshkosh.