The CNG-powered pickup is aimed at commercial and fleet buyers.

Last January, Chrysler announced that its Ram division was planning on offering a natural gas-powered pickup truck in the United States by the end of 2012.

Staying true to its word, the company has just released a full set of details about the compressed natural gas-powered 2500 Heavy Duty pickup.

The truck is powered by a 5.7-liter Hemi V8 that has been modified with different valves and a redesigned cylinder head in order to burn CNG more effectively. Other specific equipment includes a second fuel rail, and different injectors.

The CNG is stored in two tanks that are mounted in the front of the truck's 8-foot long bed. They are bolted to the frame, and covered by ultra-strong steel. The whole transformation takes place on the assembly line in Saltillo, Mexico, and Ram claims that it is the only manufacturer in North America to offer a factory-built CNG-powered truck.

Although the 2500 Heavy Duty is designed to primarily burn CNG, it automatically switches to standard gasoline when the tanks are empty. Ram says that the CNG-only range is estimated at 255 miles, and that the eight-gallon gasoline tank extends that number to 367.

By burning CNG, the 2500 Heavy Duty emits anywhere from 70 to 90% less smog-producing pollutants, while retaining a 7,650 pounds of towing capacity. Another advantage is that CNG typically costs significantly less than gasoline.

There are downsides, however. Chrysler points out that about 1,500 service stations across the United States sell CNG, but that only about half of those are accessible to the public. That explains why the CNG-powered 2500 Heavy Duty is exclusively aimed at fleet and commercial buyers.

Every natural gas-burning Ram will come with a five-year/100,000-mile warranty that covers the engine, the gearbox, and the CNG-specific components.

While Chrysler is starting out small, it believes that CNG will quickly catch on as an alternative to hybrids and diesels.

"CNG technology is a viable near-term option to lessen transportation system dependence on crude oil," said the company in a statement.

No price information for the CNG-powered 2500 Heavy Duty was released.