WILSON'S MILLS, N.C.: When trucker Luis Gonzalez drove recently from Monterrey, Mexico, to North Carolina, he expected to be the first of many who would make such a journey.

Now it appears he may be one of only a handful. Gonzalez, a driver for Transportes Olympic, based in Nuevo Leon, Mexico, is part of a controversial U.S. Department of Transportation pilot program of cross-border trucking that has the potential to end a 13-year free-trade impasse between the United States and Mexico.

Gonzalez hopes it paves the way to new destinations for him.

''I like the adventure of the open road,'' he said. ''Through this program, maybe I will know Alaska. I want to know Alaska.''

But the day after Gonzalez made the first delivery under the program dropping a load of steel at a Baptist church construction site in a small town nestled among farmland, tall trees and picturesque cottages U.S. senators voted to pull funding for it.

No one knows the exact cost of the one-year program, but the 75-23 vote to amend a transportation spending bill falls in line with an earlier U.S. House decision to pull funding. President Bush has threatened to veto the bill.

The program aims to give truckers from 100 Mexican carriers access to U.S. roads and would be a step toward implementing one of the last outstanding components of the North American Free Trade Agreement.

As many as 100 U.S. trucking companies also would gain access to Mexico.

More than $500 million has been spent on preparing to open the country's southern border to trucks, according to the Federal Motor Carrier Safety Administration, the agency overseeing the program.

Should the transportation spending bill become law, funding for the program would be suspended Oct. 1.

''This is something we've been trying to do for a number of years, but it seems every time we get close, someone in Congress wants to move the goal post,'' said John Hill, the safety agency's administrator.

With hopes of breaking a stalemate that dates 25 years, the Transportation Department announced a plan for the pilot program in February.

Administrators said it would provide an opportunity to test critics' allegations that Mexican trucks are a danger to the environment and to U.S. motorists.

The Teamsters union has been the most vocal critic of the NAFTA provisions and has worked for more than a decade to stop their implementation.

''This is the wrong program at the wrong time. It endangers motorists on highways, and it endangers national security,'' Teamsters General President James Hoffa said. ''Big business wants cheaper labor, and they don't give a damn.''

Gonzalez earns the equivalent of 13 cents per mile, plus about $20 a day for expenses. U.S. trucking giant Celadon pays truckers 31 cents or more a mile.

Truckers in the United States earn an average of about $36,000 a year, according to the Bureau of Labor Statistics.

Gonzalez's safe, uneventful delivery to North Carolina says nothing about the overall ability of Mexican carriers to operate safely in the United States, Hoffa said. ''This isn't about one truck. It's the overall fleet that they're going to come across with.''

Although the Department of Transportation has outlined stricter safety regulations for Mexican carriers than those imposed on their U.S. counterparts, problems still exist in the department's plan, the agency's inspector general said in his latest report to Congress.

The department has ''insufficient plans to check every truck every time'' it crosses the border, the report says.

Trucking companies would undergo rigorous safety inspections every three months, but driver's licenses and safety decals would be checked at each border crossing, according to the DOT plan. Initial safety checks also would be limited to the trucks on a carrier's property when the Transportation Department conducts the on-site inspection.

Along the road from Monterrey to North Carolina, Gonzalez regularly performed meticulous checks of his vehicle, stayed within drive-time limits, and once motioned to a trucker passing by that his toolbox was open, helping save motorists from a potential threat.

He tracked his driving and rest hours just as his American counterparts do with special forms and a pen. He rested for 10 hours a night, spending much of the time in his truck cab's comfortable bed under sheets printed with sunflowers.

As other truckers flew past him on the highway, Gonzalez stayed below posted speed limits.

''It's important for me to be safe,'' Gonzalez said. ''I have a wife and two daughters at home.''

Other than a Mexican license plate and a small caravan of journalists, there wasn't much that differentiated Gonzalez from U.S. truckers. His wasn't a sleepless journey made in a rickety old truck belching black smoke, as critics had predicted. Instead, it was a long haul like the thousands that take place each day in the United States.

On the way home to Mexico, he picked up a load of raw steel in Decatur, Ala.

It was headed for a factory in Mexico.

George Griffin, foreman of the construction site where Gonzalez delivered his cargo, said he doesn't mind sharing the road with Mexican truckers.

''I think the really dangerous people on the road are the young and the elderly,'' he said.

Besides, he said, Mexican companies generally provide him with better prices for construction supplies. And in construction, ''whichever company comes up with the best price gets the job,'' Griffin said.

Building Systems de Mexico, the company that made the steel rafters that Gonzalez delivered, is often a winner, he said. And with Mexican exporters expecting to shave 15 percent from their operating costs should the U.S. open its southern border, buyers such as Griffin could eventually see lower prices.

''When you're spending $300,000 for steel for a project, saving anything you can is important,'' he said.