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"This is a very important segment for us and for our customers," GM CFO Dan Ammann told CNBC at the vehicles' unveiling in New York. "It's a quarter-million units a year ... so it's a very important segment for Chevrolet and for General Motors."
The new SUVs go on sale early next year. GM has yet to release the price of the 2015 models or their fuel efficiency.
Ammann is confident both models will do considerably better than the current Suburban and Tahoe, which get 21 mpg on the highway.
He said despite the struggling economic recovery, car buyers have been out in force.
"We've had significant growth in auto sales in the last two to three years," Ammann said. "On the other hand, the economy's not showing all the signs of recovery and growth that you'd want to see, but auto sales have been very strong."
Big SUV's still in demand
Large SUVs may not sell in huge numbers as they once did in the early to mid-90's when America first fell in love with the big rigs, but it's a category of vehicles GM dominates. "We have 75 percent of the market," Ammann said.
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The Suburban and Tahoe are the two best-selling large SUVs, and so far this year, GM's large SUV sales are up 16 percent versus the industry as a whole, which is up 9.6 percent.
This at a time when the average price for a gallon of gas still hovers above $3.50 per gallon.
"At the moment consumers are spending," Ammann said. "They're in the showrooms on the weekends."
—By CNBC's Phil LeBeau. Follow him on Twitter
Questions? Comments? BehindTheWheel@cnbc.com.