“We are shocked. This has hit us hard,” said Josh Schouten, a sales representative with Kenworth Alaska.

Schouten says that nationally sales of 2007 models have dropped as much as 58 percent compared to last year.

2007 was the first year that heavy diesel manufacturers were required through EPA regulations to produce engines that would run on ULSD.

“Last year was a banner year for truck sales, as fleet owners over-bought inventory in anticipation of problems with the 2007 models using new ULSD engines,” Schouten said.

Lead times for new truck delivery in the past was sometimes eight months to a year. This year, trucks are being delivered within a month from being ordered, according to Schouten.

Truckers in Fairbanks complained that the newer trucks have as much as a 10 percent drop in power, and show higher fuel consumption as a result.

Ultra low sulfur diesel first arrived at the nation's fueling stations on Oct. 15. It was a pivotal milestone for the diesel industry and America's environmental progress and energy security. The move aimed to reduce sulfur oxide emissions, a contributor to acid rain, from on-road cargo carriers.

The effect of the ULSD has decreased emissions of sulfur dioxide. The EPA estimates that this year, thanks to a combination of cleaner diesel fuel and new engine technology, sulfur oxide emissions from heavy-duty trucks will decline by more than 100,000 tons and carbon monoxide emissions by more than 70,000 tons.

But the most significant benefits of clean diesel will be realized when new trucks have largely replaced the existing fleet by 2020, according to officials.

While heavy-duty truck sales slowed in 2007, most analysts expect purchases to increase later this year and into 2008.

“Many factors influence the acquisition of new truck and engine technologies,” said Allen Schaeffer, Diesel Technology Forum's executive director. “However, real-world experience has demonstrated that a lack of confidence in the new clean diesel engine technology should not be one of them.”

An Environmental Protection Agency mandate to use ultra low sulfur diesel in 2007 models catapulted sales of last year's models to record levels. This year's sales of diesel trucks have plummeted in Alaska as well as nationally. FILE PHOTOS/Rob Stapleton/AJOC

Schouten said that other diesel engine manufacturers would have to have a urea tank that has to be replaced periodically. Urea is a byproduct of diesel use. The Cummins diesel engines re-inject the urea into the exhaust.

According to the Diesel Technology Forum, a 2007 diesel truck emits just one-sixtieth the soot exhaust of one produced in 1988. Owners of existing diesel vehicles have the option to install new emission controls that can reduce soot emissions by more than 90 percent.

Congress is currently considering appropriations for the national clean diesel retrofit program and could provide up to $200 million this year to modernize existing vehicles and equipment.

The new clean diesel fuel also has opened the door for auto companies to offer cleaner diesel passenger vehicles.