Do drivetrain problems track state safety inspection across states?
Across U.S. states, NHTSA owner complaints about drivetrain problems run higher where state safety inspection is higher, after adjusting for the makes sold in each state. This is an association across states, not proof that state safety inspection causes this repair. Too few complaints name this repair alone, so the state safety inspection pattern is measured across all 30,824 complaints about the drivetrain, which this repair belongs to.
State reports of drivetrain problems against state safety inspection, one dot per stateEach dot is a state: how much more (or less) than expected this repair is reported there, adjusted for the makes sold in the state, against its state safety inspection (annual 2, biennial 1, none 0)
How to read it: Each dot is a state. Further right means more state safety inspection (annual 2, biennial 1, none 0); higher up means more complaints for this repair than expected (1.0 is average). If the dots climb to the right, reports of this repair rise with state safety inspection (annual 2, biennial 1, none 0).
What it shows: States with more state safety inspection (annual 2, biennial 1, none 0) tend to sit higher on the chart across 51 states: a pattern in the data, not proof of cause.
Data: State inspection programs, multi-state tables and each state agency page, joined to NHTSA owner complaints, downloaded 2026-10-06 · 51 states. Chart: CalcScrape · calcscrape.com
The 10 states with the most state safety inspection (Maine, Massachusetts, Vermont, New York, Pennsylvania, North Carolina, Virginia, Hawaii, Rhode Island, Missouri): reports of drivetrain problems run 7% above what the makes sold there would predict, and 8 of 10 are above expected. The 10 with the least (Washington, Oregon, California, Alaska, Wyoming, Utah, New Mexico, Nevada, Montana, Idaho): 9% below, and 2 of 10 are above expected.
Exceptions: New York and Hawaii are among the highest in state safety inspection but report below expected.
Split the states into thirds: the third with the least state safety inspection runs 3% above what the makes sold there would predict, the middle third 0% above, and the third with the most 1% above. Most of the state safety inspection effect sits between the lowest and the middle third.
For state safety inspection, after allowing for the 1562 comparisons we ran, luck alone would produce a pattern this strong about 1 time in 13. Take out any single state and the state safety inspection pattern still holds.
Weak spot: compare only states with similar forest and woody wetland share of land and the pattern keeps about 58% of its strength, so part of it may come from forest and woody wetland share of land instead of state safety inspection.
For state safety inspection, of the 5 exception states, 1 read the same way for the other parts of the drivetrain (so that is the system there, not this repair) and 4 are specific to this repair.
A state that inspects brakes, tires, lights and steering every year or two finds worn parts early.