Defect Scoring Methodology & Data Architecture
ModelYearGuide operates as an independent, objective consumer reference. Here is exactly how our reliability ratings, defect indices, and "Years to Avoid" verdicts are computed.
01. Primary Data Source: U.S. NHTSA
All safety defect data, recall notices, and owner complaint transcripts originate directly from the National Highway Traffic Safety Administration (NHTSA), an operating administration of the U.S. Department of Transportation.
Our ingestion pipeline continuously synchronizes with:
- Office of Defects Investigation (ODI) Complaints: Formal consumer complaints submitted under penalty of law by vehicle owners across the United States.
- Part 573 Safety Recall Reports: Mandatory manufacturer defect reports filed under federal regulations (49 CFR Part 573).
- Manufacturer Technical Service Bulletins (TSBs): Technical guidance issued to authorized franchised dealer technicians regarding known recurring component flaws.
02. Defect Risk Score (0–100 Scale)
Unlike legacy forums that merely count raw posts, ModelYearGuide utilizes a weighted severity scoring algorithm that separates minor cosmetic complaints from life-threatening mechanical failures.
Where fires and crashes carry high multipliers due to immediate safety hazards, and recalls reflect verified manufacturer engineering admissions.
03. Verdict Classification Logic
Score ≥ 55, or ≥ 500 complaints, or verified fire / stall hazard recall campaign. High probability of catastrophic financial loss.
Score 25–54, or ≥ 150 complaints. Requires thorough pre-purchase mechanic inspection and service history review.
Score < 25. Exceptional reliability record with minimal federal complaints and clean safety history.
04. Open Public Domain Attribution
United States government works, including databases produced by the National Highway Traffic Safety Administration (NHTSA), are in the public domain under Title 17, Section 105 of the United States Code. ModelYearGuide provides independent indexing, normalization, analysis, and consumer-facing visualization of these federal records.