Chevrolet, the club's official car partner, will become only the fifth shirt sponsor in the club's 134-year history from the 2014-15 season.
Announcing the agreement, which has been signed for an undisclosed amount, United's commercial director, Richard Arnold, told the club's official website, www.manutd.com: "This is a fantastic, long-term deal for the club.
"We have been partners with Chevrolet for only six weeks, but already they have produced some fantastic ideas that will benefit both the partnership and our 659 million followers around the world.
"They are a key partner on our current tour and I know they have enjoyed experiencing the buzz generated by our fanatical support and the sell-out crowds in South Africa, China, and Europe.
"It is a great thrill for those of us who work with partners all year round when an existing partner steps up to being one of our principal partners. This commitment to United and its fans will bring real benefits to everyone who cares about the club."
Chevrolet will replace Aon, whose partnership with United began in the 2010/11 season.
Alan Batey, General Motors' North America vice-president, US sales and service, said: "We are extremely proud to connect our brand, Chevrolet, with Manchester United and its passionate supporters all around the world.
"Manchester United's statistics are impressive, but this relationship goes far beyond the numbers - this relationship is about connecting our brand with the deep-seated emotion that surrounds the team everywhere it goes.
"When you consider the core values of Chevrolet, our passionate customers around the world, and our rich 100-year history, the partnership with Manchester United is a perfect fit.
"And, to be only the fifth name on the iconic red jersey is a genuine honour. We very much look forward to the road ahead and the opportunities we have in partnering with such a legendary club."