The review could end a 10-year association with Hummer, which adapted its rugged 4x4 military vehicles and launched civilian versions into the new car market.
However if it decides to sell, it could prove difficult to find a buyer for the brand as consumers continue to move away from fuel inefficient 4x4s.
It could mean a blow to the handful of Hummer dealers here, who are still in their infancy after the brand's official UK arrival last year.
They have already had to battle through the slow take-off of its sister brands Cadillac and Corvette.
Chief executive Rick Wagoner wants to re-engineer GM's business to satisfy consumer demands for smaller, cheaper and more environmentally friendly cars.
Rocketing fuel prices have begun to force American consumers to rethink their transport requirements.
Wagoner said: "These prices are changing consumer behaviour and changing it rapidly. We don’t believe it’s a spike or a temporary shift. We believe it is, by and large, permanent."
Wagoner outlined the closure of two plants in the US, one in Mexico and one in Canada, all of which produce trucks for the US market.
GM wants to cut its global production by 500,000 units to 3.5 million per year, and save $1 billion in costs. GM wants to strip $5 billion of costs in three years.