The 2001 Mitsubishi Montero Limited: not acceptable - SUV tips severely in our emergency avoidance-maneuver test.(Auto Safety - Test & Report; includes Mitsubishi rebuttal)(Cover Story)(Evaluation)

We had high expectations when we started track testing the redesigned 2001 Mitsubishi Montero Limited. Since buying a new model in August 2000,we'd put almost 7,000 miles on the vehicle and our evaluations had been mostly positive. In a brief description in our annual auto issue (April 2001), prior to track testing, we said, "Routine handling is sound if unexceptional, and the ride is compliant and well controlled." As part of a group of seven sport-utility vehicles we were testing for the September issue, it could have been one of the higher rated models.

Then something unexpected happened. In May, in one of our regular track tests for SUVs, minivans, and pickups--a short-course double-lane-change emergency-avoidance maneuver--the Montero Limited, in 8 out of 9 runs at or faster than 36.7 mph, tipped up on two wheels during a sharp right turn. In one run at 37.7 mph, it tipped up so far that the safety outriggers contacted the ground (see below).Without the outriggers, we believe, the Montero would likely have rolled over. (We attach outriggers to all SUVs and four-wheel-drive pickups for this test to protect our drivers.)

That day we ran the six other similar-sized SUVs through the same short-course test. None exhibited tip-ups or other unusual behaviors, even at speeds exceeding 38 mph. The SUVs were the Dodge Durango, Ford Explorer, GMC Envoy, Jeep Grand Cherokee, Nissan Pathfinder, and Toyota 4Runner.

Our avoidance maneuvers are designed to simulate real-world emergencies in which a driver steers sharply left into an adjacent lane--to avoid hitting an obstacle or person in the road--then quickly back to the right to avoid oncoming traffic, and left again into the original lane (see the illustration below).

We run two types of avoidance maneuvers: short-and long-course tests (see "Our Avoidance-Maneuver Tests," page 24). In both, a vehicle is driven at progressively faster speeds so that we can assess its handling characteristics under emergency-avoidance conditions. The speed at which a test vehicle completes the short course is not as important as what happens when it exceeds its handling limits. Typically, the vehicle will slide or skid sideways, knocking over cones. In most circumstances, this is a more controllable situation than a tip-up or rollover.

Sliding or skidding sideways at their handling limit is what happened with each of the other six SUVs tested on the same day as the Montero Limited. It is highly unusual for a vehicle in our tests to tip up on two wheels. Tipping up severely, we believe, demonstrates unsafe performance.

Of the 118 vehicles we have tested on the short course in the past 13 years, only the Suzuki Samurai, in 1988; the Isuzu Trooper and its twin, the Acura SLX, in 1996; and now the Montero Limited tipped up so severely as to be judged Not Acceptable.

Because of this behavior, we bought a second 2001 Montero Limited (one manufactured ten months after the first test vehicle). A recognized vehicle-dynamics expert, R. Wade Allen, was asked to assess our test …