They're big, loud and dirty. And here in the Valley, diesel engines are everywhere you turn.
That has the Environmental Protection Agency reevaluating the air quality in the area. And it has concerned JMU students and professors researching a solution.
"Alternative fuels is the way to go. When you're looking at emissions one way to get around it is to get away from fossil fuels," says JMU Professor and Environmental Engineer, Christie-Joy Brodrick.
She's helping develop fuel cell technology in a methanol-powered truck.
The clean auxiliary to a diesel engine works like a battery pack and prevents gas-guzzling idle time.
"What it does, it provides power. And we'd turn off the main engine you hear behind me and the fuel cell would power the vehicle so in idle you don't have any emissions or noise either," Brodrick explains.
Gary Pagel, like many truck-drivers, leaves his engine running for 16 hours a day. Half of that time is spent idling.
"It burns a lot of fuel sitting here idling," he admits, but he says he doesn't have a choice. He's got to keep his engine running to keep his product cool.
The alternative to diesel fuel might be expensive now, but in the long run, Brodrick says it will be better for the industry and for the environment.
JMU is working on other alternative fuels like compressed natural gas and biodiesel. Researchers hope to work with city vehicles in Harrisonburg next.