Reporter Bob Hansen filled up on regular last week for $2.75 a gallon.  Truckers buying diesel where he stopped paid only $2.10.   How did they do it, when average prices nationwide are hovering closer to $4 per gallon every day?  Simple.  They left the country.

California NBC affiliate KNSD explains, "Hansen ventured south to Tijuana to find out just how much money could be saved to fill up a gas tank."

It's a growing trend on America's southern border.  New Mexico's Las Cruces Sun-News reports, "The high price of fuel has motivated some people to cross into Mexico to buy diesel and regular gasoline."

Why is Mexican gas cheaper than fuel just miles away across the U.S. border?  Reuters reports that the Mexican government has instituted "A $19 billion fuel subsidy, meant to shield Mexicans from spiraling world oil prices."  It's easy for the government to do that in Mexico -- gas stations there are all run by PEMEX, a government monopoly.  The subsidy measure "means Mexicans are paying $1.40 less for a gallon of gasoline than U.S. motorists."  The Mexican government is taking a risk with the subsidy, since "the money earmarked for fuel subsidies this year is more than what Mexico spends annually on education," and many critics "say the government is squandering profits from high crude prices just when it should be spending them on projects like roads, schools, refineries and oil platforms -- all things that would boost economic growth."  But the tactic is keeping fuel prices in Mexico low compared to what Americans pay.

And Americans in border states are increasingly benefitting from the subsidy by stocking up on cheap Mexican gas.

Bob Pelham tells the Sun-News that he "makes the trip to Palomas every couple of months" in his diesel-powered Ford F-250.  Pelham brings more than 20 empty gas containers with him, and, he adds, "I try to arrive on an empty tank."

Some say he's taking a risk, but the issue is far from clear-cut.  Bob Gallagher, president of the New Mexico Oil and Gas Association, tells the Sun-News "The gasoline you put into your car has a significant impact on how your engine runs.  There are extremely tight rules and regulations here in the United States. I would not think that I would want the chance of saving a couple of dollars to potentially costing me a new vehicle."

But KNSD says reporter Hansen "spoke with a variety of San Diego mechanics who have shops by the border and they said they haven't seen any unique problems from cars that get their gas from Mexico."

With diesel fuel, there is an additional complication.  New EPA regulations require diesel sold in the U.S. to carry less sulfur than what is sold in Mexico.  New diesel engines are designed to run on the ultra-low-sulfur fuel.  Filling up with higher-sulfur diesel might void the warranty on those new engines.

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