What 393.71H-CDHSLMII means in plain language
Your citation is for a defective fifth wheel assembly. The regulation requires that the fifth wheel on your commercial motor vehicle be in good working condition, show no excessive wear, and be properly secured to the frame.
The fifth wheel is the coupling device that connects your tractor to a semi-trailer. It bears enormous forces—the weight of the trailer, dynamic loads during acceleration and braking, and lateral stress during turns. If it's damaged, worn beyond safe limits, or not bolted down properly, the trailer can shift, separate, or become unstable during operation.
Inspectors check for cracked welds, loose bolts, worn slippers (the sliding surfaces), damaged castings, and improper positioning. Even a small defect here triggers enforcement because the consequences of failure—a trailer breaking away on a highway—are catastrophic.
What our enforcement data actually shows
Across our 13 million+ inspection records, this code ranks #1595 by citation volume. Across 56 all-time citations in our database, 54 vehicles were placed out of service immediately—a 96.4% out-of-service rate. This is dramatically higher than the all-FMCSR average of 31.4%, meaning inspectors view this defect as an urgent safety issue that cannot be ignored.
Enforcement has been steady and recent. Over the last 12 months, we recorded 35 citations. In the last 90 days alone, 11 citations were issued. The trend shows fluctuation month to month, but the enforcement pattern is consistent: when a fifth wheel defect is found, the vehicle is almost always taken out of service on the spot.
Who gets cited most
Our inspection records show California leads with 7 citations in the last 180 days, all 7 resulting in out-of-service status (100% rate). Massachusetts follows with 5 citations, also all out-of-service. Maryland had 4 citations, all out-of-service.
The out-of-service rates are uniform across these top states—all three show 100% enforcement rates, confirming that inspectors in high-traffic regions treat this defect as non-negotiable. Across all states citing this code, the pattern holds: nearly every violation results in the vehicle being pulled from service.
Our data shows fleets including Red Roots Landscape Inc, Cranston Walter C and Son Inc, and Boulevard Garage Inc with 2 citations each in our all-time records. This is not a code concentrated among a few carriers; it appears distributed across different operation types and sizes.
How severe is this compared to similar codes
In the vehicle maintenance category, this code's enforcement pattern stands out. The code 393.9(a), Inoperable Required Lamps, has been cited 660,737 times with only a 15.4% out-of-service rate. Code 393.11, Lighting Devices/Reflectors, shows 179,734 citations with 1.8% out-of-service rate. Code 393.78, Windshield Condition Defective, has 157,894 citations but only 0.3% out-of-service rate.
By contrast, 393.71H-CDHSLMII's 96.4% out-of-service rate places it in a category of safety-critical defects that inspectors will not permit on the road. The low citation volume (56 all-time) reflects that most drivers and fleets catch and repair fifth wheel problems before roadside inspection. When it is found, the response is swift and absolute.
How to avoid it
A fifth wheel defect citation is preventable through disciplined pre-trip inspection and scheduled maintenance:
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Walk the fifth wheel before every trip. Look for visible cracks in the weld seams, especially where the assembly connects to the frame. Run your hand along the casting to feel for rough spots or separation. Check that the device sits level—tilting indicates bolt looseness or frame damage.
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Check all bolts for tightness. The fifth wheel bolts to the frame at multiple points. Use the right wrench or socket and verify each bolt is snug. Vibration and stress can loosen fasteners over weeks of operation. If a bolt spins freely or feels loose, tighten it immediately.
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Inspect the slider and slippers. The fifth wheel slides forward and backward to adjust coupling height and weight distribution. Verify the slippers (friction surfaces) are not worn smooth or cracked. If the slider binds or moves too freely, the assembly is not functioning safely.
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Monitor for grease and corrosion. Fifth wheels should be greased at regular intervals per the manufacturer schedule. Lack of lubrication accelerates wear. Conversely, corrosion on the casting or bolts signals age and material degradation. If your fifth wheel shows heavy rust or crystallization, it may be near end of service life.
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Know your vehicle's maintenance history. Our inspection data shows Ford, RAM, and Volvo models appear most frequently in citations. If you operate one of these makes, schedule fifth wheel inspection as a core item in your preventive maintenance plan, not a reactive repair.
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Do not defer fifth wheel repairs. Co-occurring violations in our database include brake defects and inadequate lighting. When one critical system is neglected, others often are too. If an inspector or mechanic flags a fifth wheel issue, repair it before the next trip. Operating with a known defect is both dangerous and an invitation to enforcement.
The 96.4% out-of-service rate for this code is not a threat—it is evidence that the regulation works. Inspectors catch the defect and prevent a catastrophic failure. Your job is to prevent the inspector from catching it in the first place.