If you thought filling up your 15-gallon tank costs a lot, consider the plight of Steve Silva of Napa. His fleet of 22 trucks uses approximately 2,000 gallons of fuel a month.

“With the economy slowing down and high gas prices, it was a double whammy,” said the owner of Steve Silva Plumbing.

But as fuel prices have fallen as much as $1 a gallon in California over the past month, Silva said, “Now we have a little relief.”

While cheaper fuel costs are a welcome change, some businesses continue to watch expenses gallon by gallon. Unlike some service providers, Silva did not pass on the higher expenses to his customers.

“We basically absorbed the higher gas prices,” he said. “It affects our bottom line.”

The company tracks each truck and their gas station purchases, he said. And if you think Silva or many other small and medium-sized business have a line on their own gas supplies, you’re wrong.

“We go to the pump like everyone else,” said Silva. “There’s no discount for volume, that’s for sure.”

Silva said higher fuel prices caused him to reconsider aspects of his operations, such as the number of trucks he uses.

 “We looked at the guys traveling the longer distances and made sure they were in more efficient trucks,” he said.

“We parked two or three of the gas guzzlers — those getting eight to 10 mpg. They were older utility trucks that carry a lot of weight.”

Silva also looked into buying smaller pickups, but he isn’t sure the gas savings would cover the expense of a new vehicle. For now, he’s holding off on any purchases.

Cutting costs

Other businesses are seeking creative ways to control fuel costs. Enterprise might be best known as a rental car company, but it is providing a different service to Ruben Perez of Napa Electric.

“We were spending a lot of money on older vehicles with bad gas mileage,” Perez said. Putting a $3,000 transmission into a van worth $2,000 didn’t make much sense.

After analyzing maintenance and fuel costs for his older trucks, the business decided to lease 15 new vans; from Enterprise.

“We have about 50 vehicles we’re trying 15 with Enterprise to see how it goes. So far it’s been great. They paint them, they outfit them and they take the old ones back.”

With more than 50 trucks to gas up and maintain, at the peak of fuel prices this summer, the company spent as much as $18,000 a month on gas.

The Enterprise program will result in savings of $25,000 a year in gas, maintenance and repair, predicts office manager Tiffany Kuehl.

Besides new vehicles, simple ideas also make a difference.

“We made the guys plan better,” said Perez, for example, avoiding last-minute deliveries.

Perez also asks suppliers to deliver directly to the job site, not to Napa Electric’s headquarters.

“We did a lot of restructuring just to cut down on the trips Upvalley,” he said.

Perez isn’t the only one keeping a close eye on gas bills. Gary Garaventa, at Garaventa’s Florist & Gifts, has three trucks and spends about $1,500 a month on gas, he said.

Garaventa hasn’t increased his delivery fees, but “we’re being more diligent about grouping our deliveries,” he said.

“We try and make one or two runs at a time instead of three to five. But it’s hard.”

The business delivers from St. Helena to American Canyon. “My trucks are gone all the time,” he said.

Garaventa said he welcomes the recent drop in gas prices, but said, “I don’t know if it’s enough to make a difference yet.”

“We’re trying to do the best we can for our customers and not have to charge and arm and a leg for a delivery.”

Garaventa and others may find more relief on the way as retail gasoline prices dipped for a 17th week since July 4, falling below $2 a gallon in a number of states and as low as $1.77 in Des Moines, Iowa.

Retail gasoline prices fell to a national average of $2.22 a gallon, dragged down by the falling price of crude oil, which now costs 60 percent less per barrel than it did in mid-July.

The average price has fallen nearly 32 percent, and nearly $1 a gallon statewide, in the past month and, according to AAA, could be headed to $2 a gallon nationally by year’s end.

Oil prices continued to slide, to near $55 a barrel Thursday before rebounding slightly, as bad economic news from the world’s largest economies heightened fears that a global downturn will slash demand for crude.

“As the global economy continues to weaken, we’re going to see further downward pressure on oil,” said Stephen Roach, chairman of Morgan Stanley Asia, in Singapore. “I think we’ll certainly challenge the $50 threshold. We could challenge the $40 threshold.”

The Associated Press contributed to this story.