The redesigned 2009 Nissan Murano was the best performer in new crash tests which showed the current crop of midsize SUVs should fare better in head-on collisions.

The Insurance Institute for Highway Safety tested nine 4-door midsize SUVs -- putting them through front, side, and rear crash tests.

Results released Tuesday showed the redesigned Murano was the only model among the nine to achieve the highest ratings in all three tests.

The institute, which is funded by the U.S. insurance industry, praised Nissan Motor Co. for making electronic stability control -- which helps prevent the vehicle from swerving -- standard on the 2009 Murano. On previous models the system was offered as an option.

"You don't know what kind of crash you're going to get into, so you want a vehicle that affords the best protection in the most common kinds of crashes," said Joe Nolan, the institute's senior vice president, in a statement released Tuesday morning.

The institute's spokesperson Russ Rader said overall, the new results showed SUVs are faring better when compared to similar crash tests performed in 2001 by the institute.

"Back in 2001, when we tested a group of midsize SUVs, only about half of them earned the top rating of 'Good' in the frontal test," Rader told CTV's Canada AM from Washington on Tuesday.

"In this case, all but one of them did."

General Motors' Hummer H3 was the only SUV in the group that didn't get the top rating in the frontal crash test.

The Hummer got the second-highest rating of "acceptable" because the test showed a likelihood of injury to the driver's right leg in a frontal crash.

The frontal crash test simulates a 40 mph (64 kph) crash.

The H3 also got an "acceptable" rating in the side crash test, and the worst rating of "poor" in the rear crash test.

In a statement, GM spokesperson Alan Adler said the H3 "meets or exceeds all federal crash safety standards. The Insurance Institute tests represent one measurement of crash performance."

Adler added that GM designs its head rests to meet a variety of driver sizes, rather than the average-sized man used in the institute's tests.

The Jeep Liberty, Jeep Wrangler 4-door, and Kia Sorento, meanwhile, performed the worst in the side test.

The institute downgraded side crash results for the H3, Kia Sorento and Chrysler LLC's Jeep Liberty/Dodge Nitro because they lacked air bags that protected the chest and abdomen (the Liberty and Nitro are built on the same vehicle platform).

All three vehicles had curtain air bags. While they protect the head, the institute said its tests showed a likelihood of injuries to the driver's rib cage in a side crash.

"We were surprised, frankly, that we had some marginal and poor performers in the side impact tests," Rader told Canada AM. "SUVs should have an advantage in this test, because the crash-test dummies are sitting up a little higher."

The Jeep Wrangler also got a low rating in the side crash tests because its side air bags are optional, and the institute tests vehicles without optional equipment. The Wrangler was the only vehicle tested that didn't feature standard side air bags.

The side crash simulates what would happen if the vehicle was struck in the side by an SUV at 31 mph (50 kph).

In addition to the H3, the worst performers in the rear crash test were the Mitsubishi Endeavor and the Jeep Liberty/Dodge Nitro.

The institute said three vehicles -- the Mitsubishi Endeavor, Mazda CX-7 and Mazda CX-9 -- would have been top safety picks, but they performed relatively poorly in the rear crash test.

The rear crash test simulates a 20 mph (32 kph) test, and measures the risk of injury from whiplash -- the most serious injury reported in 2 million insurance claims in the U.S. each year.

The KIA Sorento earned the lowest rating in the combined three categories.

Top four performers of the midsize SUV crash test results:

Source: The Insurance Institute for Highway Safety

With files from The Associated Press