Thanks to GPS attached to the 18 wheelers, the owner tracked one down about two miles away.
His map showed the other big rig was in Fresno County.
"He went over there at about 9:45 am," says Tony Botti with the Fresno County Sheriff's Office. "He sees his truck, he sees a couple of guys and a U-Haul truck parked near there. He confronts them. Next thing you know, these guys shoot at this man."
The Fresno County Sheriff's Office says the truck owner fired back multiple rounds. The two suspects then got into a U-Haul and sped away.
"that's an MO that a lot of thieves do," Botti said. "They'll go rent vehicles. They'll never return them. They get reported stolen, and they basically rent it for the purpose of being their crook mobile."
Investigators believe the suspects may have stolen the trucks to siphon fuel out of them after finding a diesel tank on the road.
"They fill it up with diesel that they steal on farms and siphoning out of vehicles, and then they'll turn around and sell that fuel on the black market at half price," Botti said.
Officials say the tank appears to have slid out of the U-Haul as the suspects drove off.
"With the prices going up, it is a problem that we've seen more with gas and diesel thefts," Botti said.
In September, a Lemoore man was arrested for stealing thousands of gallons of fuel from farming equipment and selling it illegally.
"If you ever want a true barometer of what the economy is doing, just look at a crook," Botti said. "They know supply and demand better than anybody."