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Nov 17 (Reuters) - J.B. Hunt Transport Services Inc was the first major U.S. trucking company to back Tesla Inc's new "Semi" electric trucks on Friday, saying it had reserved multiple vehicles for use on the U.S. West Coast.
Neither company responded to calls seeking to clarify exactly how many of the vehicles Hunt was reserving after Tesla unveiled the Semi on Thursday without specifying prices.
Hunt's statement followed a rejection of the new vehicles on Thursday by Old Dominion Freight Line Inc, the United States' fourth-largest less-than-truckload carrier and other carriers were also more cautious.
"Carriers have been skeptical about the heavy-duty tractor applicability to their models, given questions regarding torque, total hauling capacity, and recharging infrastructure," said Benjamin Hartford, a sector analyst with brokerage Baird.
"(J.B. Hunt) the first mover, particularly with regard to Tesla, but we expect other carriers to follow as electric tractor viability becomes proven."
Shares of J.B. Hunt were down 1.8 percent while Tesla shares were up 1.7 percent in early trading in New York.
Tesla has been trying to convince the trucking community that it can build an affordable electric big rig with the range and cargo capacity to compete with relatively low-cost, time-tested diesel trucks.
In a showy launch on Thursday, Tesla chief Elon Musk said the truck could go up to 500 miles (800 km) at maximum weight at highway speed, allowing it to drive from Los Angeles to San Francisco and back without recharging.
Diesel trucks are capable of traveling up to 1,000 miles (1,600 km) on a single tank of fuel.
Tesla showed off the semi on a webcast which offered reservations for the truck at $5,000 each, but Musk did not discuss reservation volume.
A spokesman for United Parcel Service Inc said the courier had nothing to announce regarding Tesla's vehicles but would always look for options that fit its needs.
Brad Pinchuk, chief executive of Dubuque, Iowa-based Hirschbach Motor Lines, said his firm was looking to test non-diesel big-rig options but needed longer ranges than Tesla could provide and speedier fuel-up times.
Pinchuk said he plans to buy two hydrogen-powered trucks made by Salt Lake City-based electric Nikola Motor Company when they are available in 2020.
"Its a different application putting liquid hydrogen into tanks so it will be very similar sort of situation to diesel," Pinchuk said. "Youd be able to fuel up. It would take about the same amount of time to fuel up a diesel and go about the same distance."
(Reporting by Sonam Rai and Arjun Panchadar in Bengaluru; Editing by Anil D'Silva and Nick Zieminski)