What 393.201D means in plain language
FMCSR 393.201D addresses frame accessories that are not properly attached to your vehicle. Frame accessories include items like mud flaps, steps, handholds, bumpers, and any other equipment fastened to the truck frame. When an inspector cites you for this code, they're saying that one or more of these attachments are loose, missing fasteners, cracked, or otherwise insecure.
The core requirement is straightforward: any accessory bolted or welded to your frame must be secure and in good working condition. A loose mud flap, a cracked step, or fasteners that have backed out all trigger this violation. It's a defect that can worsen during transit and potentially create hazards on the roadway.
What our enforcement data actually shows
Across our database of 13 million+ roadside inspections, we've recorded 1,288 citations for 393.201D since records began. In the last 12 months alone, inspectors issued 916 citations for this code, and in the past 90 days, that number hit 275. This ranks 393.201D at #653 of 3,036 FMCSR codes by citation volume.
The critical takeaway for your case: this code carries a 0.3% out-of-service rate. Out of 1,288 all-time citations, only 4 trucks were placed out of service. That compares sharply to the all-FMCSR average OOS rate of 31.4%. In practical terms, getting cited for 393.201D is unlikely to result in an immediate roadside shutdown. The vast majority of drivers cited for this violation—1,284 of 1,288—were allowed to continue their route after receiving the citation.
The trend over the last year shows enforcement activity climbing. September 2025 saw 85 citations, and March 2026 spiked to 160 citations. This suggests increased inspector focus on frame integrity during the spring inspection season.
Who gets cited most
Our inspection records show state-level variation in enforcement. Texas leads by a significant margin with 471 citations over the last 180 days, with a 0.0% out-of-service rate. Illinois recorded only 4 citations in that same window but had a 50.0% OOS rate—a material difference that likely reflects different inspector severity or vehicle conditions at the time of citation. New Mexico had 1 citation with a 0.0% OOS rate.
Carrier-wise, our data shows fleets such as Evans Delivery Company Inc (USDOT 38111) with 15 all-time citations for this code, and Maritime Services Ltd (USDOT 337587) with 12 citations. Neither pattern suggests systemic frame attachment problems; rather, it reflects the volume of inspections these larger carriers encounter.
Among vehicle makes, Freightliners dominate the citation count with 326 citations, followed by Kenworths at 306 citations. This mirrors the market share of these brands on U.S. highways, not a defect pattern unique to either manufacturer.
How severe is this compared to similar codes
393.201D sits in the vehicle maintenance category. Peer codes in the same category show a wide OOS-rate range. Code 393.78 (Windshield condition defective) has issued 157,894 citations with only a 0.3% OOS rate—identical to 393.201D. Code 393.47E (Slack adjuster defective) has 180,363 citations but a 0.0% OOS rate. By contrast, code 396.3(a)(1) (Inspection/repair/maintenance general) has 236,919 citations and a 45.3% OOS rate—far more severe.
The data tells you that frame accessories, while cited regularly, are treated as lower-severity maintenance items. They're defects to correct, not typically grounds for immediate vehicle removal from service.
How to avoid it
Frame accessory defects often cluster with other vehicle maintenance issues. Our inspection records show that 393.201D commonly co-occurs with:
- Inoperable required lamps (393.9) — 58 shared inspections in the last 90 days. This suggests inspectors finding multiple maintenance gaps in a single truck.
- Fuel system leaks (396.5B) — 51 shared inspections. Again, a sign of overall maintenance neglect.
- Brake tubing/hoses inadequate (393.45B2UV) — 46 shared inspections, pointing to a pattern where frame and fastener issues co-occur with brake system degradation.
Here's how to stay ahead of this citation:
- Perform a frame walk-around daily. Before you pull out, walk the full perimeter of your cab and chassis. Look for mud flaps that are torn or hanging loose. Check that all steps, grab handles, and bumper brackets are tight. Shake them if you can reach them safely.
- Check fasteners monthly. Vibration on the highway causes bolts to back out. During monthly maintenance, use a flashlight to inspect all visible frame fasteners. Tighten any that have loosened. Pay special attention to mud flap mounting bolts and step fasteners.
- Inspect after rough roads. Heavy bouncing or pothole impacts can dislodge accessories. If you've driven through severe terrain, do a quick visual inspection or have a mechanic check key attachments.
- Document your pre-trip findings. If you notice a loose fastener during your pre-trip, report it to dispatch or your shop immediately. Log it. That shows diligence if you're cited later.
- Don't defer small loose parts. A loose mud flap seems minor, but inspectors cite it regularly. It's a five-minute fix in most cases. Address it during your next service stop rather than carrying a defect for days.
The data shows that frame accessories are a low-OOS-rate citation, meaning you won't be shut down. But it's also a high-frequency enforcement area, so fixing these issues before an inspector finds them keeps your compliance record clean and prevents accumulation of violations on your CSA score.