HARRISBURG -- Independent trucker Bob Carr, of suburban Harrisburg, spends about $1,200 a week on diesel fuel, up from $700 last year.

Owner-operator Bob Dobrosky is on target to spend $88,000 on diesel fuel this year, up from $57,000 last year.

Their routes haven't changed, just the price of diesel fuel.

They were among 100 truckers who rallied yesterday outside the state Capitol while more than 100 of their brethren circled the statehouse in tractor-trailers and box trucks, horns blaring, to protest taxes on fuels and the proposed tolling of Interstate 80.

"If they toll 80 that would be all my profits gone. The margin is that close," said Mr. Dobrosky, 64, whose route sends him between Armstrong County and Waterbury, Conn.

He's not alone, said Mark Kirsch, an owner-operator from Lebanon County, who organized the rally.

"Drivers are going broke every day. Drivers are parking their trucks," he said.

At 38.1 cents per gallon, Pennsylvania has the nation's highest tax on diesel fuel and, at 32.3 cents, the 11th-highest on gasoline.

While lawmakers and state policymakers have opposed increasing fuel taxes to raise additional money for road and bridge repairs, eliminating them isn't the solution, said Rich Kirkpatrick, spokesman for the Pennsylvania Department of Transportation.

"There's no guarantee that such a cut would be passed along to consumers at the pump," Mr. Kirkpatrick said. "Obviously, fuel prices are a worldwide concern. The decisions on the setting of those prices are not made in Harrisburg."

Combined revenue from the gasoline tax -- a liquid fuels tax of 12 cents, an oil company franchise tax that is indexed to the wholesale price, and a storage tank fee of 1.1 cents -- and the diesel tax amounted to nearly $1.3 billion in the 2006-07 fiscal year, Mr. Kirkpatrick said.

The rates for both taxes have remained stable since 2006, said Revenue Department spokeswoman Stephanie Weyant.

Meanwhile, federal fuel taxes amount to 18.4 cents per gallon for gasoline and 24.4 cents per gallon for diesel.

Per-gallon fuel prices in Pennsylvania averaged $3.28 for regular unleaded gasoline and $4.33 for diesel yesterday. That's up from $2.70 and $2.84, respectively, a year ago.

The cost of fuel affects people whether they drive or not, Mr. Kirsch said. High fuel prices translate into higher costs of transporting goods and that means higher prices for almost everything.

A cacophony of air horns nearly drowned him out as he used a megaphone and then a small sound system to speak to the crowd outside the Capitol.

Mr. Kirsch and other organizers urged attendees to call and write their state and federal representatives to urge a repeal of fuel taxes, an end to the plan to toll Interstate 80 and to impose caps on oil company profits.

"We need each and every outlet we have to let them know we don't want what they are trying to give us," said interstate trucker Michael S. Schaffner, of Nocona, Texas, who was in the area and joined the rally.