But pickup drivers who don't need their trucks to haul loads or equipment are contributing to the buildup of greenhouse gases much more than the average car owner, says Glade Sowards, who heads the Task Force on Global Warming for the state Division of Air Quality.
"There are legitimate needs for those vehicles," he says. "But a full-size pickup contributes 12 to 13 tons of greenhouse emissions a year compared to a midsize car that accounts for about 8 tons. If you're driving across the valley as a commuter, a small car makes a difference."
In January, new federal regulations took effect for diesel engines.
They included such requirements as particulate filters and engine components to burn off soot. The new rules also forced oil companies to produce ultralow sulfur diesel fuel.
That will help air pollution along the Wasatch Front during inversions, Sowards says, but won't cut global warming.
"Catalytic converters and particulate filters help reduce that type of pollution," he adds. "But when it comes to CO2, or other greenhouse gases, they're mostly coupled with fuel consumption. The new diesel fuel will not reduce greenhouse gases."
Decades of regulatory loopholes have allowed light trucks to pollute at higher levels than passenger cars, a Union of Concerned Scientists report said.
An analysis by the organization revealed that fuel efficiency for light trucks could be improved significantly, while at the same time reducing smog-forming exhausts.
But the U.S. auto industry has fought higher fuel-efficiency standards as well as stricter anti-pollution measures.