One problem related to frame rust has been reported for the 2000 Mitsubishi Montero Sport. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2000 Mitsubishi Montero Sport based on all problems reported for the 2000 Montero Sport.
I heard a noise while driving at low speeds while hitting bumps, when I stopped driving and looked under the vehicle I noticed the frame was rusted completely through to the other side, and especially bad where the rear differential bracket is attached to the frame, its so loose it doesn't look safe to drive.