LISLE, Ill. — Daniel Ustian, chairman, president and CEO of Navistar is retiring effective immediately, the company announced today.

Lewis Campbell, former chairman, president and CEO of Textron Inc., has been appointed Executive Chairman of the Board of Directors and interim CEO. Troy Clarke, president of Truck and Engine operations, will be appointed president and CEO of Navistar.

Navistar has been struggling as it tries to comply with Environmental Protection Agency standards, and the last few months have seen the company switch engineering tactics and enlist the help of Cummins to bring an EPA-compliant engine lineup to market next year.

“Lewis Campbell is a high-caliber executive who brings to Navistar deep and broad strategic, technical and operational skills and a proven track record of leadership with global industrial companies — including twenty-four years of experience in product design, engineering and manufacturing in General Motors’ automotive, trucking and component businesses and seventeen years in senior leadership positions at Textron including more than 10 years as Chairman, President and CEO. We are very pleased to have him join the team,” said Michael Hammes, Navistar’s independent Lead Director.

Campbell said that he’s honored to join the Navistar board, and that a search for a long-term CEO will begin at “an appropriate time” and will include both internal and external candidates. Hammes thanked Utsian, and pointed out that during his 37-years at Navistar, revenue grew $7.7 billion as it expanded globally, and “diversified its product portfolio, including the addition of Navistar’s military business.”

Clarke, prior to his appointment as President of Truck and Engine operations, served as President of the Company’s Asia Pacific operations. Clarke joined Navistar in January 2010 as Senior Vice President, Strategic Initiatives. Previously, Clarke spent more than 35 years with General Motors Co. where he served in a variety of roles, including President of General Motors North America, President and Managing Director of GM’s Mexico operation, Vice President of Manufacturing and Labor Relations, and President of GM Asia Pacific. He has a B.S. in mechanical engineering from General Motors Institute, as well as an M.B.A. from the University of Michigan.

Campbell was Chairman of Textron Inc., from 1999 to 2010, CEO from 1998 to 2009 and President for most of the period from 1994 to 2009. Campbell initially joined Textron as CEO in 1992, and before that spent 24 years at General Motors where he served in a variety of roles including Vice President and General Manager, Flint Automotive Division for Buick/Oldsmobile/Cadillac, as well as Vice President and General Manager, GMC Truck. Campbell holds a B.S. in mechanical engineering from Duke University.