In a matter of weeks, a 41-mile stretch of toll road with the fastest speed limit in the country will open in Central Texas.

But truck drivers may steer clear of the new high-speed road, said John Esparza, president of the Texas Motor Transportation Association, which represents the trucking industry in Texas.

“It’s going to be a deterrent, yes,” Esparza said of the road’s 85 mph speed limit.

The Texas Department of Transportation has said it pursued a higher speed limit for the new portion of State Highway 130 from Austin to Seguin in part to entice drivers away from more congested highways. Agency officials have said engineering tests demonstrated that an 85-mph speed limit is safe for the new toll road.

While he acknowledged that some truck drivers drive faster than 65 mph, most trucking companies try to keep drivers from traveling faster than that speed, both out of concerns for safety and because it reduces a truck's gas mileage, Esparza said.

Many trucking companies install technology on their trucks to block them from traveling too fast.

"We know it’s common industry practice to do that, particularly as fuel prices continue to rise," said Sean McNally with the American Trucking Association. “A truck going 75 [mph] uses 27 percent more fuel than one going 65."

The American Trucking Association has urged the Texas Transportation Commission to reverse its decision ton the 85 mph speed limit for the new toll road. The group favors a maximum 65 mph speed limit for all highways.

So far, higher speed limits do not appear to be deterring trucks on other Texas roads, TxDOT spokeswoman Veronica Beyer said. She pointed to the portion of SH 130 that is already open to traffic. TxDOT increased the speed limit there to 80 mph in April. Since then, the number of vehicles with three or more axles has increased slightly.

"The data clearly shows that trucks are steadily increasing their use of this safe and efficient route," Beyer said.

Chris Lippincott, spokesman for the SH 130 concession company, the private consortium that is building and will operate the new toll road, said speed won’t be the determining factor in whether trucks decide to take advantage of it.

“I think anyone who’s been on I-35 when it’s uncongested at night will tell you there are plenty of trucks that are willing to drive that fast,” Lippincott said. “We think our facility will give the trucking community good choices considering speed, congestion, topography and access points.”

The new toll road might become more attractive to all vehicles in a few years if development along the I-35 corridor continues, leading to more congestion, Lippincott said.

"A company might make a different decision in fall of 2012 than they would in 2016," Lippincott said.