Direct answers on 393.207G defective air suspension exhaust citations, OOS rates, enforcement trends, and next steps based on 13M+ inspection records.
Ranks #1,411 of 3,146 FMCSR codes by citation frequency • OOS rate of 1.8% is below the FMCSR-wide average of 33.3%.
No / defective air suspension exhaust control
Direct answers grounded in TruckCodex inspection data
No—this citation will almost certainly not pull your truck out of service. Across our inspection records, only 2 out of 102 citations for 393.207G resulted in an out-of-service order, yielding a 2.0% OOS rate. That's far below the 31.4% average OOS rate across all FMCSR codes. You should be able to continue operating while you schedule repairs.
393.207G is relatively uncommon. It ranks #1413 out of 3,036 FMCSR codes by citation volume. In the last 12 months, we recorded 64 citations nationally. For context, the most-cited vehicle maintenance codes like 393.9 (inoperable lamps) have generated 660,737 citations and 396.3 (general inspection/repair) has 236,919. You're dealing with a low-frequency violation, which may indicate your vehicle type or operating region sees less focus on air suspension exhaust controls.
First, document the specific defect the inspector noted. Then: (1) Schedule an inspection of your air suspension exhaust system immediately; (2) Check related brake and fuel system components—our data shows 393.207G often co-occurs with slack adjuster defects (6 shared inspections in the last 90 days), steering issues (5 shared), and fuel system leaks (3 shared); (3) Correct the violation and obtain proof of repair; (4) Plan for a follow-up inspection if your state requires it. Don't delay—the citation is on your record.
No, it's among the least serious maintenance violations. Its 2.0% OOS rate is lower than nearly every peer code: 393.9 (inoperable lamps) sits at 15.4% OOS, 393.11 (lighting devices) at 1.8%, and 396.3 (general inspection/repair) at 45.3%. The only comparably lenient codes are 396.17C and 396.17 (no proof of periodic inspection), both at 0.0% OOS. This suggests inspectors view air suspension exhaust defects as correctable maintenance issues rather than safety show-stoppers.
Texas dominates the citation count. In the last 180 days, we recorded 29 citations in TX with a 0.0% OOS rate. North Carolina had only 1 citation but that one resulted in an out-of-service order (100% rate). The data is thin outside these two states, reflecting that 393.207G remains a low-volume citation nationally. If you operate primarily in Texas, you're in the zone where inspectors are most likely to flag this defect.
Citations are steady but volatile month-to-month. Over the last 12 months, we saw a spike in July 2025 (10 citations) and January 2026 (10 citations, with 1 OOS), followed by drops in subsequent months. The 90-day average (April–June 2026) shows 12 citations total—roughly 4 per month. No strong seasonal pattern emerges. The citation rate remains low and unpredictable, so compliance is more about maintaining your air suspension exhaust system regularly than reacting to a surge in enforcement.
Yes, you can submit a challenge through the Federal Motor Carrier Safety Administration's DataQs portal if you believe the citation is factually or legally incorrect. Since 393.207G is an equipment-condition violation, your challenge should focus on evidence that the air suspension exhaust system was not actually defective at the time of inspection. Documentation—such as repair receipts, pre-inspection photos, or a technician's statement—strengthens your case. DataQs decisions are reviewed by FMCSA, but the process typically takes 30–60 days.
Freightliners lead by far: 29 out of 102 all-time citations involved FRHT vehicles. Kenworth trucks came second with 14 citations, followed by Volvo (11), Peterbilt (10), International (8), and Mack (8). If you drive a Freightliner, you're in the demographic most frequently flagged for air suspension exhaust defects. This may reflect the age, mileage, or maintenance patterns of the Freightliner fleet rather than inherent design flaws.
Where 393.207G is most commonly cited (last 180 days)
Other violations commonly found on the same inspection (last 90 days)
TruckCodex aggregates official public-sector datasets. See the Source registry for dataset-level coverage and the Freshness log for last-import timestamps.
Census, SAFER, SMS, Licensing & Insurance (L&I), roadside inspections, crashes, and authority history.
Vehicle recall campaigns, defect investigations, and consumer safety complaints (SCRS).
Cross-border carrier registry and Canadian recall campaigns where applicable.
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