FMCSR 393.75A3: Flat Tire & Audible Air Leak Violations Explained

Yes — almost certainly. Despite being coded as not OOS-eligible on paper, our inspection records show a 92.9% out-of-service rate across all 43,804 all-time citations for 393.75A3. That means 40,713 of those inspections ended with the vehicle placed out of service. Inspectors are applying discretionary authority under the North American Standard OOS criteria for flat tires and audible air leaks, and they are using it consistently. The national average OOS rate across all FMCSR codes is 31.4% — this violation runs nearly three times that rate. Plan on not moving your truck until the tire or air leak is corrected and the inspector clears you.

The severity weight for 393.75A3 is not published in the available data, so a precise point value cannot be stated here. What is clear is that this violation falls in the Vehicle Maintenance BASIC, which is scored against both the carrier and the driver. CSA uses a time-weight multiplier: violations in the most recent 6 months count at full weight, those 7–12 months old count at half weight, and those older than 12 months drop off driver and carrier SMS scores entirely. Given the 92.9% OOS rate attached to this code, FMCSA's scoring system treats equipment-based OOS events as more severe than non-OOS citations in the same BASIC.

Stop the vehicle, do not move it until the defect is corrected. Here are the immediate steps:

1. Fix the tire or air leak on the spot — a flat tire or audible leak is what triggered the OOS order in 92.9% of recorded cases.
2. Document the repair — get a receipt or written confirmation; you will need it for DataQs if you contest.
3. Check your other systems — in our inspection records, 393.75A3 citations in the last 90 days co-occurred with inoperable lamps (393.9, 1,260 shared inspections), defective windshields (393.78, 656), and fuel system leaks (396.5B, 453). An inspector who found a flat tire likely walked the whole truck.
4. Notify your safety department immediately — the citation enters the FMCSA SMS within 30 days and affects both your record and the carrier's Vehicle Maintenance BASIC score.

Yes — it is substantially more serious than most peer codes in the Vehicle Maintenance category. The all-FMCSR average OOS rate is 31.4%. Among comparable codes in the same category, inoperable required lamps (393.9) carry a 6.9% OOS rate, windshield defects (393.78) carry 0.3%, and no proof of periodic inspection (396.17C) carries 0.0%. A 393.75A3 citation at 92.9% OOS dwarfs all of them. It also ranks #72 out of 3,036 FMCSR codes by total citation volume, putting it squarely in the top 2.4% of all cited regulations. Flat tires and audible air leaks are treated as immediate road-safety hazards, not paperwork deficiencies.

Yes, you can file a DataQs Request for Data Review (RDR), but equipment violations are harder to win than documentation errors. Because 393.75A3 is a physical defect — a flat tire or an audible air leak the inspector observed at the roadside — the burden is on you to show the finding was factually incorrect. Successful challenges usually involve evidence that the violation was recorded on the wrong vehicle, the VIN or unit number was entered incorrectly, or the inspector's notes contradict the physical inspection form. Gather your repair receipts, photos taken at the scene, and the driver vehicle inspection report from that date before filing. DataQs submissions are reviewed by the issuing state agency, and the decision can take 30–90 days.

Texas, New Mexico, and North Carolina are the top three states for this violation over the last 180 days. Texas alone accounts for 8,410 citations with a 90.2% OOS rate. New Mexico recorded 1,896 citations — every single one resulted in an OOS order, a 100.0% OOS rate. North Carolina logged 1,268 citations with a 98.3% OOS rate. If you regularly run lanes through the Southwest or Southeast, your pre-trip tire inspection is not optional — it is the single most reliable way to avoid an OOS order in those corridors. Illinois also appears in the top states with 309 citations and a 97.1% OOS rate.

Extremely urgent, and yes, citations are trending upward. Our inspection records show 23,855 citations for 393.75A3 in just the last 12 months, compared to 43,804 all-time — meaning more than half of all recorded citations came in the past year alone. Monthly volume climbed from 1,028 in April 2025 to 2,388 in March 2026. The last 90 days produced 5,627 citations. Enforcement intensity is clearly rising, not falling. With a 92.9% OOS rate, a flat tire or audible air leak found at inspection does not result in a warning — it results in the vehicle being parked. Pre-trip tire checks need to be a documented, non-negotiable part of every dispatch.

It follows both. Under FMCSA's CSA methodology, Vehicle Maintenance BASIC violations are attributed to the carrier's SMS profile based on the USDOT number on the inspection report. At the same time, driver-based violations are linked to the driver's CDL number and appear in the driver's individual SMS record. Our inspection records show large carriers accumulating significant citation counts — Swift Transportation at 147 all-time citations, FedEx at 133, and J.B. Hunt at 119 — which illustrates the carrier-side impact. But drivers who accumulate vehicle maintenance violations across multiple carriers can face intervention from FMCSA based on their individual driver record. Neither party escapes the citation.