The G.M. pickup issue has also raised questions about the value of the side-impact test.

In the agency's side-impact test, the S40 received the top rating, five stars.

The safety administration plans to release detailed data soon on side-impact tests, but as yet none are publicly available.

However, they did not conduct a side-impact test.

There are two kinds of side-impact tests.

Sport utilities do better than large cars and almost as well as minivans on side-impact tests that the Government recently began conducting.

Detailed results for federal front- and side-impact tests and rollover tests can be found online at www.safercar.gov.

But it turns out side-impact tests are quite a different animal.

By contrast, the government's side-impact tests simulate what happens when a car strikes other vehicles in the side.

In a few weeks, the agency will propose tougher minimum performance requirements that vehicles must pass in side-impact tests.