Direct answers on 393.47(c) citations: OOS rates, CSA points, repair urgency, and what to do next based on 13M+ roadside inspection records.
Ranks #638 of 3,146 FMCSR codes by citation frequency • OOS rate of 6.9% is below the FMCSR-wide average of 33.3%.
Mis-matched slack adjuster effective length
Direct answers grounded in TruckCodex inspection data
Not likely. Across our inspection records, only 6.9% of 393.47(c) citations resulted in out-of-service placement—101 vehicles stopped out of 1,460 total citations. This is significantly lower than the national average of 31.4% across all FMCSR codes. Most drivers receive a citation and are allowed to continue operating, though repair is required.
This violation carries a CSA severity weight of 7. In the FMCSA's Safety Management system, your total points depend on when the violation occurred and how many similar violations appear within a 12-month window. A single citation from today will contribute 7 points to your safety profile; multiple violations within 30 days may be weighted differently. Consult your carrier's safety team for your specific CSA impact.
Immediate steps:
It's moderate. While 393.47(c) has a 6.9% OOS rate, the peer code 393.47E (slack adjuster defective) has a 0.0% OOS rate, and the brake-related code 393.9 (inoperable lamps) also sits at 6.9%. However, inspection/repair violations like 396.3(a)(1) push OOS rates to 45.3%, making those far more severe. Brake actuator defects are serious safety issues but don't automatically ground your vehicle on the spot.
Yes. Your carrier can submit a DataQs (Database Quality System) request to challenge the citation if evidence shows it was inaccurate. Equipment findings—like brake actuators—are often contestable if you can demonstrate the part was not defective at the time of inspection, or that the inspector made a factual error. Submit documentation showing proof of repair or pre-inspection condition. FMCSA reviews these challenges and may remove the citation from your record.
Enforcement has dropped significantly. Our database shows 1,460 all-time citations for 393.47(c), ranking it #618 out of 3,036 FMCSR codes. More tellingly, there have been zero citations in the last 12 months and zero in the last 90 days—indicating this violation is now rarely cited at roadside. This suggests either improved vehicle maintenance or a shift in inspector focus to other codes.
Our records show CNC LOGISTICS S DE RL DE CV (USDOT 2726203) leads with 15 citations, followed by JESUS GILBERTO GALVAN MENDOZA (USDOT 3005565) with 14, and TRANSPORTES 4 AMIGOS S DE RL DE CV (USDOT 3971467) with 13. These are primarily smaller or owner-operator carriers. Most large fleets maintain brake systems more consistently, resulting in fewer defect citations across their operations.
Freightliner units dominate our citation data: FREIGHTLIN (151 citations) and FRHT code (138 citations) account for nearly 300 of 1,460 total citations. Kenworth (KW: 105 citations, KENWORTH: 63 citations), International (INTERNATIO: 79 citations, INTL: 56 citations), and Volvo (59 citations) round out the top makes. This reflects the prevalence of these tractors in the fleet, not necessarily their reliability.
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.
TruckCodex is an independent aggregator; it is not affiliated with FMCSA, NHTSA, EIA, or Transport Canada. Always verify compliance-critical information directly with the originating agency.