(Reuters) - Most of the midsize SUVs did not fare well in a new small overlap front-crash test conducted by an influential U.S. safety group, in yet another jolt to the industry already shaken by safety concerns.

Chevrolet Equinox and GMC Terrain from the General Motors Co were the only vehicles to earn the highest rating of "good" in the test, according to results released by the Insurance Institute for Highway Safety (IIHS) on Tuesday.

Out of the nine participating models, Toyota Motor Corp's Highlander was rated "acceptable" while rest of the group earned "marginal" or "poor" ratings.

The worst performers in the test were Mazda Motor Corp's CX-9 and Honda Motor Co's Pilot, which sustained "significant structural collapse," IIHS said.

The small overlap test was developed after research showed that about 25 percent of serious injuries and deaths occurring in frontal crashes were in small impacts, such as the front of a vehicle clipping the front of an oncoming car or striking a tree or pole.

According to IIHS, such a test is more challenging than the long-standing moderate overlap test conducted by the Institute since 1995.

The new test results come in the backdrop of several vehicle recalls from automakers. GM, which has recalled 2.6 million cars for faulty ignition switches that caused air bags to deactivate, may also have a defect in air bags in 2003 to 2010 Chevrolet Impalas, an auto safety watchdog group said.

Ford Motor Co said on Monday it would recall about 434,700 vehicles mainly in North America due to two separate and unrelated issues.

In January, subcompact cars including the Fiat 500 and Honda Fit performed the worst of any vehicle segment so far in a tough new test that assessed what happens when the front corner of a vehicle hits another car, a utility pole or tree.

In another test by IIHS in August last year, half of the small cars did not fare well.

In May last year, the IIHS had said most of the small SUVs tested for safety in crashes did not fare well in more stringent tests. The 2014 Subaru Forester was the only one among the 13 small SUVs, also called crossovers, on the U.S. market tested that achieved a "good" rating in a new front crash test.

"GOOD"

GMC Terrain
Chevy Equinox