Silverado -- 5; Tundra -- 4

Silverado -- 5; Tundra -- 4

The National Highway Traffic Safety Administration (NHTSA) has released its frontal-impact crash test ratings for the 2007 Toyota Tundra and 2007 Chevrolet Silverado full-size pickup trucks.

The score is Chevrolet Silverado -- five stars; Toyota Tundra -- four stars.

NHTSA tested the Regular and Double Cab versions of the Tundra; both achieved four stars.

NHTSA tested Regular and Extended Cab versions of the Silverado. It scored five out of five stars. (It can be assumed that the virtually identical GMC Sierra also rates five stars.)

The Silverado matches the same five-star scores previously earned by the current Ford F-150 and Dodge Ram 1500 pickups for driver and front-passenger safety in a frontal impact.

Toyota has boasted the Tundra goes head-to-head with Big Three pickups on payload and towing capacities as well as safety. It had expected five-star scores.

Four out of five stars represents an 11% to 20% chance of serious injury. A five-star rating indicates serious injury is reduced to 10% or less in a frontal crash.

"The Big Three are certain to try to capitalize on this from a marketing and promotional standpoint, because the Tundra is a pretty strong truck," said Dan Edmunds, director of Edmunds.com's automotive testing. "They're going to be looking for a weakness to exploit."

Indeed, a Ford spokesman told The New York Times the Tundra's safety rating could be incorporated into Ford's F-150 advertising.

A Toyota spokesman said the Tundra met or exceeded all crash standards in its own testing. The spokesman said its engineering team would be examining what happened.

Michelle Krebs:  is Editor-in-Chief of AutoObserver.com. Follow @AutoObserver on Twitter.