WASHINGTON -- Dave Gares, an independent truck driver since 1974 who hauls mostly soft drinks these days, said he never dreamed he'd be paying more than $4 per gallon for diesel.

It takes 220 gallons to fill up his tractor-trailer rig, which gets a little more than six miles per gallon on the road. It costs Gares up to $1,400 to fill up, with the added cost of fuel additives to boost his truck's mileage. He said he has to absorb the increases to stay competitive.

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"You can't charge it back to the shipper, so it comes out of your own wallet," said Gares, of Lebanon, Pa., one of more than 100 truckers who drove to Washington on Monday to demand changes from Congress. "Now you have to start looking at how to cut back."

Horns blaring in a deafening fanfare, the convoy of truck drivers was impossible to ignore as the group rode into the nation s capital. Members of Truckers and Citizens United circled the National Mall before parking their tractors and dump trucks at RFK Stadium. From there, about 100 protesters marched and took shuttles to the Capitol for an afternoon rally under a downpour of rain.

The national average price of a gallon of regular gasoline is a record $3.51, according to a recent survey of stations by AAA and the Oil Price Information Service. The price for diesel -- used to transport most food, industrial and commercial goods -- is $4.20 a gallon.

"The high price for oil is hurting our economy," organizer Mark Kirsch said. "This isn't just about truckers, this is about United States citizens overall."

To bring relief, they are urging Congress to stop subsidizing big oil companies, to release oil from the Strategic Petroleum Reserves, and stop exporting oil from Alaska, among other things.

Many of the truckers drove to Washington from Harrisburg, Pa., and other areas as far north as Maine. One passenger circling the city s monuments and government agencies held a sign that read "Enough is Enough," and a driver used a bullhorn to yell at Congress as he passed by.

Sen. Jeff Sessions, R-Ala., who met with members of Truckers and Citizens United in the afternoon, said it's clear the truckers are suffering.

"It's particularly heartbreaking to hear their stories, because not only is there an economic slow down, which means they are hauling less," but a surge in diesel prices adds more burdens, he said.

Truck drivers are planning a similar protest Thursday in New York City and another unspecified event May 5. Organizers said Wall Street is responsible for driving up prices with no regulation from Congress.

William Lockridge, of the Washington Metropolitan Area Truckers Association, said independent truckers are barely breaking even.

"If the truck stops, the economy stops," he said. "We need help, and we need it now."

Nathan and Tara Horn of Normal, Ill., said they were visiting museums and other sites, but came to the Capitol to see the truckers' protest.

"Just knowing the influence that our citizens have to talk to our congressmen and senators ... This is awesome," said Nathan Horn, stopping to watch the trucks pass in the rain.

Tara Horn said she works at a food bank where more people are seeking assistance because of rising food prices. The price of fuel has made transporting goods across the U.S. more expensive.

Traffic was not significantly affected by the convoy of vehicles, though a few truckers drove through red lights as they honked their horns.

Gares said he thought fuel prices would level off once they surpassed $3 per gallon, but it only got worse, he said.

"It s a dog eat dog world anymore."

The truckers said they want Congress to issue an immediate cap on gasoline, diesel and heating oil prices. They are demanding a $2 a gallon cap on all of the fuels.