Ten weeks of rising diesel fuel prices are the latest blow to the trucking industry, which has struggled to overcome a series of economic challenges recently.

For trucking companies, the average $3.74 a gallon fuel — a 70-cent increase from last year — comes at a time when they would otherwise be gearing up for an economic turnaround. In addition, many still are recovering from pricey expenditures to meet clean-air rules.

Many Valley companies pass on costs to customers with fuel surcharges, but for others that's not an option.

Fuel typically makes up about one-third of trucking companies' budgets, said Kristen Monaco, an economics professor who specializes in trucking at California State University, Long Beach. And with most trucks averaging 7 miles per gallon and driving hundreds of thousands of miles each year, those costs add up.

"Even when it goes up slightly, it tends to take a huge chunk out of their budget," she said.

In the central San Joaquin Valley, which is known as a shipping hub, companies are doing what they can to make up for the fuel prices.

"It's just about surviving," said Manny Nanner, dispatch manager of Valley National Express, which has 40 trucks based in Fresno delivering produce to Texas and the Midwest.

"There's companies out there, I don't how they do it," he said.

All this comes at a time when orders are beginning to pick up industrywide -- and companies normally would be hiring more drivers and buying more trucks, said Michael Shaw, spokesman for the Sacramento-based California Trucking Association.

Read more of this story at FresnoBee.com