(Recasts lead, adds GM, Ford results, analyst comments)
By Bernie Woodall and Ben Klayman
DETROIT, Jan 5 (Reuters) - Automakers reported strong December U.S. sales Monday, boosted by falling gas prices, but industry executives and analysts cautioned that growth would slow this year after five years of rapid recovery from the recession.
General Motors Co easily beat analyst expectations, logging a 19 percent gain to 274,483 vehicles, the best December for the No. 1 U.S. automaker in seven years. Ford Motor Co sales of 220,671 were up just 1 percent, missing expectations.
"U.S. auto sales are dancing to a very different (and we believe unsustainable) beat," Morgan Stanley analyst Adam Jonas said in a research note.
He suggested U.S. auto demand has outpaced economic, wage and housing growth rates, thanks largely to easy credit access for consumers.
Spurred by low gasoline prices, pickup truck and large SUV sales surged in the month.
Sales of GM pickup trucks Chevrolet Silverado and GMC Sierra surged 35 percent to 81,273, outpacing the F-Series pickups from Ford, which were flat at 74,355 vehicles. Ford's F-150 pickup truck sales remain limited due to the rollout of a new version.
Fiat Chrysler Automobiles' Ram Truck brand pickup sales soared 32 percent to 44,222 units.
Auto sales are an early indicator each month of consumer spending. A Reuters poll of 11 analysts showed expectations for a 10.5 percent gain in December, helped by low gas prices which boosted demand for pickup trucks and large sport utility vehicles.
U.S. average gasoline prices are 34 percent lower than a year ago, and in much of the country, are less than $2 per gallon.
A poll of 35 economists by Thomson Reuters showed they expect, on average, a December annualized selling rate of 16.9 million vehicles, the highest for the month since before the 2008-2009 industry downturn amid the recession.
Full-year sales for 2014 are expected to finish around 16.5 million vehicles, matching the number in 2006. Rising demand has allowed automakers to boost prices for their vehicles, however.
Kelley Blue Book, an industry source for vehicle valuations, said Monday the average transaction price for a new vehicle sold in the U.S. market in December was a record $34,367, up 2.5 percent from a year ago.
Pricing fell 1.2 percent for hybrid and other alternative fuel cars as gasoline prices continued to fall, KBB said.
GM's December transaction prices grew 4 percent from a year earlier to $38,816, KBB said.
Fiat Chrysler's U.S. sales jumped 20 percent in December on strong Jeep SUV and pickup truck sales, but still missed analysts' expectations. FCA's sales of 193,261 for the month were the highest since 2006 for the company once known as Chrysler.
Nissan Motor Co's December U.S. sales narrowly beat expectations, while Honda Motor Co <7267.T) sales fell short.
Nissan on Monday said its U.S. sales grew 7 percent to 117,318 vehicles, and that 2014 sales of 1.39 million vehicles were a company record.
However, while Honda's U.S. sales rose 1.5 percent to 137,281 vehicles, the figure was well short of analysts' expectations of about 143,000 vehicles in December. For the year, Honda sales were up 1 percent at 1.54 million vehicles. (Editing by W Simon and Bernadette Baum)