FMCSR 393.45(a): Brake Tubing/Hoses — Driver Q&A

Yes — and the numbers make this one of the most dangerous citations to receive at a roadside inspection. Although 393.45(a) is technically listed as not OOS-eligible on its face, our inspection records show that across all 2,669 all-time citations, 2,515 vehicles were placed out of service — a 94.2% OOS rate. That is nearly three times the all-FMCSR average of 31.4%. In practice, inspectors are finding conditions severe enough to pull trucks regardless of the baseline eligibility flag. If your brake tubing or hoses are worn, chafed, crimped, or visibly damaged, assume you are getting parked.

393.45(a) carries a CSA severity weight of 7. That score is then multiplied based on how recently the violation occurred — inspections within the last 6 months carry the highest multiplier (3×), dropping to 2× between 6 and 12 months, and 1× after that, up to the 3-year lookback window. A severity weight of 7 at the 3× multiplier equals 21 weighted points in the Vehicle Maintenance BASIC. Because this violation lands on the carrier's Safety Measurement System record, fleets with even a handful of 393.45(a) hits can see measurable BASIC percentile movement.

Act immediately — do not move the vehicle until the brake tubing or hose issue is inspected and repaired by a qualified mechanic. Given that 94.2% of all 393.45(a) citations across our database resulted in an OOS order, continuing to operate creates both a safety risk and additional regulatory exposure. Steps to take:

1. Document the defect — photograph the damaged tubing or hose before any repair.
2. Get a written repair order showing the specific part replaced and the technician's certification.
3. Keep the repair receipt — you will need it if you file a DataQs challenge or if the citation resurfaces in a compliance review.
4. Notify your safety department immediately so the carrier's BASIC score can be monitored.

Yes — 393.45(a) is significantly more serious in practice than most peer codes in the Vehicle Maintenance category. Our inspection records show a 94.2% OOS rate for this code. Compare that to some of the highest-volume codes in the same category: 393.9(a) (inoperable required lamps) sits at a 15.4% OOS rate across 660,737 citations, and 396.3(a)(1) (inspection/repair/maintenance) comes in at 45.3% across 236,919 citations. Even the all-FMCSR average is just 31.4%. At 94.2%, a 393.45(a) finding almost always means the vehicle is going nowhere. The code also ranks #472 out of 3,036 FMCSR codes by citation volume, so inspectors know it well.

Yes, you can submit a DataQs Request for Data Review (RDR) to challenge a 393.45(a) finding. Because this is an equipment-condition violation rather than a documentation violation, a successful challenge typically requires evidence that the cited condition did not actually exist — for example, a pre-trip inspection report showing no defects, repair records predating the inspection, or a signed statement from a certified mechanic. DataQs challenges on equipment findings are harder to win than documentation disputes, but they are not impossible. Submit your RDR through the FMCSA DataQs portal and attach all repair documentation. The state agency that conducted the inspection reviews the request and issues a determination.

Our inspection records show that Freightliner-platform trucks dominate the citation counts for 393.45(a), but for state geography, the data points to heavy enforcement concentrated among fleets running high-mileage corridors. Among vehicle makes, FRHT leads with 287 citations, followed by FREIGHTLIN with 182 and UTIL trailers with 168. The top carrier names in our database for this code include LANDEATER TRANSPORT LLC, AVM SHIPPING INC (6 citations each), and WESTERN EXPRESS INC, WERNER ENTERPRISES INC, and PRICE TRANSFER INC (5 citations each). Note: the STATISTICS block for this code does not include a state-level breakdown, so we are not able to name specific states without risking inaccuracy.

Repair urgency is extremely high, but enforcement volume has gone to zero in the most recent period tracked. Our database shows 0 citations in the last 90 days and 0 in the last 12 months, against an all-time total of 2,669. That drop likely reflects a reclassification of how inspectors record brake hose defects rather than inspectors ignoring the problem — the 94.2% OOS rate across all historical citations confirms this has always been treated as a critical safety defect. Do not interpret the recent zero-citation trend as reduced risk. A vehicle with damaged brake tubing is still an imminent hazard, and inspectors will act on it under related brake codes.

It follows both, but in different ways. Under FMCSA's CSA system, a 393.45(a) citation is an equipment violation that counts against the carrier's Vehicle Maintenance BASIC score, because the carrier is responsible for maintaining the vehicle in safe operating condition. However, if the driver conducted or signed off on a pre-trip inspection that failed to identify the defective brake tubing, that inspection failure can also be reviewed during a carrier compliance audit and may reflect on the driver's record. The safest position for both parties is thorough pre-trip documentation and immediate defect reporting — which is exactly what the 94.2% OOS rate for this code makes non-negotiable.