March 20 (Bloomberg) -- Toyota Motor Corp.'s redesigned Tundra, battling full-size pickups from U.S. automakers, didn't get the top rating for frontal crash safety achieved by rivals.

The Tundra fell one star short of the perfect five-star rating for driver safety in head-on collisions in a test by the U.S. National Highway Traffic Safety Administration. Big pickups from General Motors Corp. and Ford Motor Co. earned five stars.

The miss may threaten Toyota's bid to grab U.S. sales from GM and Ford in the pickup segment, which accounted for three of the five best-selling vehicles in 2006. Toyota, the world's second-biggest automaker, unveiled the 2007 Tundra last month.

``Toyota is still learning in big trucks, and this is an indication that Toyota still has some more learning to do,'' said Dennis Virag, president of Automotive Consulting Group in Ann Arbor, Michigan. ``The other guys are looking for any little advantage, and they'll certainly jump on this one.''

Vehicles get a top frontal-crash rating when they are judged to have a 10 percent or less possibility of a driver injury requiring immediate hospitalization in a head-on collision at 35 miles per hour. A four-star rating means an injury risk of 11 percent to 20 percent.

`Very Surprised'

Toyota was ``very surprised'' by the four-star rating, said Bill Kwong, a spokesman for the company's U.S. operations in Torrance, California. The Toyota City, Japan-based automaker graded the Tundra at five stars in internal tests using NHTSA standards, he said.

``Safety is important, but it's not a very big part of the truck market,'' Kwong said. ``They want to haul stuff, carry stuff.''

U.S. sales of the Tundra, including those from the 2006 model year, fell 20 percent this year through February compared with a 0.4 percent decline for all full-sized pickups, according to Autodata Corp. Sales of the Chevrolet Silverado from Detroit- based GM, including the redesigned 2007 model, gained 15 percent. Ford's F-Series dropped 13 percent.

Toyota opened a $1.3 billion plant in November in San Antonio, where it plans to make as many as 200,000 redesigned Tundras this year. The truck's other full-sized competitors in the U.S. are DaimlerChrysler AG's Dodge Ram, Nissan Motor Co.'s Titan, GM's GMC Sierra and Ford's Lincoln Mark LT.

Other Models

Within most pickup brands, certain models earned fewer than five stars for either driver or passenger safety. The extended- cab Chevrolet Silverado 1500 Classic, for example, got four and three stars for driver and passenger protection, respectively.

Nissan's Frontier and Isuzu Motors Ltd.'s I-290 pickups, both smaller than the Tundra, got four-star frontal-crash ratings in the NHTSA tests. The Nissan Frontier with extended cab was the only pickup to be rated three stars for both driver and passenger safety.

The NHTSA results were reported earlier today by the New York Times.

Toyota's American depositary receipts gained 50 cents to $132.05 at 4:01 p.m. in New York Stock Exchange composite trading. GM's shares rose 26 cents to $29.35 and shares of Dearborn, Michigan-based Ford increased 6 cents to $7.88.

To contact the reporter on this story: Greg Bensinger in New York at gbensinger1@bloomberg.net

Last Updated: March 20, 2007 16:15 EDT