How Do SUVs Stack Up?

The 2009 Nissan Murano was the best performer in new crash tests of midsize sport utility vehicles, while the Hummer H3 had one of the poorest showings, according to results released Tuesday by the Insurance Institute for Highway Safety.

The institute, which is funded by the insurance industry, said the redesigned Murano was the only vehicle among the nine tested to get the highest rating in front, side and rear crash tests. It praised Nissan Motor Co. for making electronic stability control standard on the 2009 Murano. The system, which helps prevent swerving, was an option on previous models.

"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," Joe Nolan, the institute's senior vice president, said in a statement.

How The Tests Are Conducted

The institute's tests are tougher than those run by the U.S. government, and automakers often change their vehicles and pay the institute to rerun tests to garner better scores for advertising. Among the 94 SUVs from the 2008 model year crash-tested by federal regulators, only 10 earned less than four out of five stars.

Midsize SUVs have improved in the institute's crash tests. In 2001, only half of the midsize models received good ratings in the frontal offset test. In this year's test, all but the Hummer H3 do, and it got an acceptable rating.

How vehicles are evaluated: The Institute's frontal crashworthiness evaluations are based on results of 40 mph frontal offset crash tests. Each vehicle's overall evaluation is based on measurements of intrusion into the occupant compartment, injury measures recorded on a Hybrid III dummy in the driver seat, and analysis of slow-motion film to assess how well the restraint system controlled dummy movement during the test.

Side evaluations are based on performance in a crash test in which the side of a vehicle is struck by a barrier moving at 31 mph. The barrier represents the front end of a pickup or SUV. Ratings reflect injury measures recorded on two instrumented SID-IIs dummies, assessment of head protection countermeasures, and the vehicle's structural performance during the impact. Injury measures obtained from the two dummies, one in the driver seat and the other in the back seat behind the driver, are used to determine the likelihood that a driver and/or passenger in a similar real-world crash would sustain serious injury to various parts of the body. The movements and contacts of the dummies' heads during the test also are evaluated. Structural performance is based on measurements indicating the amount of B-pillar intrusion into the occupant compartment.

Rear crash protection is rated according to a two-step procedure. Starting points for the ratings are measurements of head restraint geometry - the height of a restraint and its horizontal distance behind the back of the head of an average-size man. Seats with good or acceptable restraint geometry are tested dynamically using a dummy that measures forces on the neck. This test simulates a collision in which a stationary vehicle is struck in the rear at 20 mph. Seats without good or acceptable geometry are rated poor overall because they can't be positioned to protect many people.

SUV Crash Test Results

How 10 SUVs fared in crash tests from the Insurance Institute of Highway Safety - rankings include good, acceptable, marginal and poor.

Front:
2009 Nissan Murano: Good
2007-08 Mazda CX-7: Good
2007-08 Mazda CX-9: Good
2007-08 Mitsubishi Endeavour: Good
2008 Suzuki XL7: Good
2006-08 Hummer H3: Acceptable
2007-08 Jeep Wrangler: Good
2008 Jeep Liberty: Good
2007-08 Dodge Nitro: Good
2007-08 Kia Sorento: Good

Side:
2009 Nissan Murano: Good
2007-08 Mazda CX-7: Good
2007-08 Mazda CX-9: Good
2007-08 Mitsubishi Endeavour: Good
2008 Suzuki XL7: Acceptable
2006-08 Hummer H3: Acceptable
2007-08 Jeep Wrangler: Marginal
2008 Jeep Liberty: Marginal
2007-08 Dodge Nitro: Marginal
2007-08 Kia Sorento: Poor

Rear:
2009 Nissan Murano: Good
2007-08 Mazda CX-7: Marginal
2007-08 Mazda CX-9: Marginal
2007-08 Mitsubishi Endeavour: Poor
2008 Suzuki XL7: Marginal
2006-08 Hummer H3: Poor
2007-08 Jeep Wrangler: Poor
2008 Jeep Liberty: Poor
2007-08 Dodge Nitro: Poor
2007-08 Kia Sorento: Good

For the full rankings, click here.

About The IIHS

The Insurance Institute for Highway Safety is an independent, nonprofit, scientific and educational organization dedicated to reducing the losses - deaths, injuries, and property damage - from crashes on the nation's highways.

The Highway Loss Data Institute shares and supports this mission through scientific studies of insurance data representing the human and economic losses resulting from the ownership and operation of different types of vehicles and by publishing insurance loss results by vehicle make and model.

Both organizations are wholly supported by auto insurers.