The rear-drive sedan will debut in late 2010 as a 2011 model. Cadillac executives are arguing over whether to offer a V-6 option.
"There is a big debate as to whether it is four only. I think that is a bridge too far," said Cadillac General Manager Jim Taylor at a press event here.
"There is a piece of the team who is thinking, 'Well, with this whole fuel economy and gas thing, we ought to go all the way, say, to fours.' We are resisting that at this stage."
Also in the equation are new federal fuel economy standards that begin to take effect in the 2011 model year.
The car, whose name has not been announced, will be positioned under the CTS. In Europe, Cadillac markets the BLS, a small front-drive sedan and wagon. It shares a platform with the Saab 9-3 and is powered by a four-cylinder diesel or gasoline engine. Both engines are turbocharged.
BLS sales have been disappointing. Taylor said his team is discussing whether to call the U.S. car the BLS.
He said the V-6 debate centers on whether U.S. buyers would accept only a four-cylinder engine — even if it gets a turbocharger like Saab's.
"I don't think Americans are going to become un-American that fast," said Taylor.
"They still want power. We still have big open roads. People do not want to stop enjoying driving."