NHTSA complaint #578456 (ODI reference 10154778) concerns a 2006 TOYOTA 4RUNNER and was filed on April 7, 2006. The owner reports the failure occurred on March 6, 2006. The vehicle had 1,200 miles on the odometer at the time of the incident. The report was geocoded to Wyoming based on the filer's self-reported location. The affected component is categorized as suspension:rear:springs:leaf spring assembly:u-bolt, leaf spring to axle, one of NHTSA's standardized taxonomy codes used to group defect patterns across make, model, and year.

The filer flagged the following severity indicators: crash: no, fire: no, injuries: 1, fatalities: 0. No crash, fire, or fatality was associated with this report, which places it in the early-warning stream rather than the priority-review stream. Because a VIN was supplied, this complaint is tied to a specific vehicle and not just a model-year cohort.

Individual complaints are consumer-submitted and unverified by NHTSA engineers — the agency's role at this stage is to collect, index, and make them searchable. What matters for federal action is the pattern: when many owners of the same TOYOTA 4RUNNER cohort independently describe similar suspension:rear:springs:leaf spring assembly:u-bolt, leaf spring to axle failures, defect investigators have grounds to open a PE and request manufacturer data. Related filings for the same vehicle and component appear below, and the detail page for the full 2006 TOYOTA 4RUNNER shows the complete component-level complaint distribution alongside any active investigations or recalls.