Driving fuel, water, ice and the U.S. mail across Iraq is dangerous business, but for many civilian contractors it is worth the risk for a chance to serve their country. This is the untold story of America's unsung heroes working in Iraq (search).

"This job is unlike any other job in the world. Soon as you go outside the wire, you know, I mean, it's dangerous," said driver Paul Chevalier.

Civilian contractors working for KBR (search), the Houston-based Halliburton subsidiary, drive more than 3.3 million miles a month in Iraq to transport fuel and supplies for the U.S. Army.

Seventeen drivers have died in ambushes.

Many braving the job came for the opportunity to earn three times their normal salary, but have discovered a calling to help the Iraqi people since getting behind the wheel in the liberated country.

Ruthie Brisbane, a 54-year-old grandmother working in Iraq, explained what she wants for the Iraqis: "That they can be free and live without fear ... I want to see them live a life very close to ours."

The scale of KBR's operation in Iraq is mind-boggling. One day's work includes trips by 700 trucks that deliver more than 300 million gallons of fuel and log more than 50 million miles. And being bombed and shot at is all part of the job.       

"Your main concern is just get out of it. Keep the truck rolling. You don't want to stop. And you just get out of the kill zone," said driver trainer Randy Ross.

Battalion Commander Lt. Susan Davidson, the woman in charge of all air and ground supply movements, said that everyone is affected by the loss of life. "I say a prayer for them and
then examine the problem to make sure it doesn't happen again," she said.

Camp Anaconda (search), KBR's massive trucking hub in the Iraqi desert north of Baghdad, is home to these unsung heroes. Their work provides coalition forces with the bare necessities they need to operate.

"If we don't roll, the military doesn't get what they gotta have to function. So we gotta roll," said convoy commander Clay Henderson.

And when trucks get into trouble and have to be left behind, guys like Gary Smith risk their lives to recover them. "I'm here serving, serving my country. I would rather fight 'em here then fight 'em back home," said the recovery driver.

But it doesn't take a life-threatening situation to make these workers look out for one another.

"It's close knit, I seen it already. It's a close-knit family. Once you get outside the wires, everybody's got your back," said driver Ken Andrews.

These truckers are ready to roll on some of the most dangerous roads in the world, where they
know that death and serious injury could come at any time.

Click on the video box near the top of this story to watch a report by FOX News' John Cookson.