Announcement comes tomorrow, according to WSJ, citing sources, but buyer's name will not be released. GM has been looking at sub-$500 million offers from various parties, including a Chinese investor.

GM has been studying strategic alternatives for the brand for a year, and has settled on a buyer that could take over the brand by the end of the third quarter, these people said. GM will continue producing Hummer H2 and H3 trucks and SUVs at plants in Louisiana and Indiana for the buyer.