What 383.93 means in plain language
Your commercial driver's license comes with restrictions for a reason. Some drivers are restricted from operating vehicles with air brakes, others from manual transmissions, doubles, or tank vehicles. Code 383.93 covers operating a commercial motor vehicle in violation of any restriction printed on your CDL.
This isn't about whether you can physically drive a certain type of truck. It's about whether your license permits you to drive it. If your CDL has an air brake restriction and you're operating a truck with air brakes, you're in violation of 383.93. The same applies if you're restricted from doubles but driving a double combination, or restricted from tanks but hauling a tank load.
Restrictions exist because they were conditions of your CDL issuance—often tied to medical findings, your training record, or endorsement status. Operating outside those restrictions is a federal violation that federal and state inspectors take seriously.
What our enforcement data actually shows
Our inspection records show a striking pattern with 383.93: across 13 million inspections in our database, we have recorded zero citations for this code in the all-time period, zero in the last 12 months, and zero in the last 90 days.
With zero documented citations, there is no out-of-service rate to calculate—the metric remains at 0.0% across all enforcement outcomes in our records. This does not mean the violation doesn't occur or that it isn't enforced. It likely reflects one of two realities: either inspectors rarely encounter drivers operating so blatantly outside their restrictions, or the violation may be recorded under related codes that capture similar compliance gaps.
The absence of citations in our database is itself instructive: it suggests that either most drivers understand and comply with their CDL restrictions, or the violation occurs infrequently enough that it doesn't show up in roadside inspection patterns we've tracked.
Who gets cited most
Because our enforcement records show zero citations for 383.93 across all time periods and all states, we cannot identify a top state distribution or carrier pattern for this specific code. The data in our database does not support any geographic or fleet-level ranking for 383.93 enforcement.
If you've received a citation for 383.93, you are in a rare category—and that rarity underscores how seriously the violation is viewed when it does occur. Most drivers either know their restrictions or don't test them.
How severe is this compared to similar codes
To understand where 383.93 sits in the enforcement landscape, our inspection records show related driver-fitness violations that share the same category but occur far more frequently:
CDL - wrong class (383.23(a)(2)) appears in 50,385 citations in our database with a 98.4% out-of-service rate. This code covers operating a CMV in a class you're not licensed for—a more common violation than restriction violations.
Operating a CMV without a valid CDL (383.23A2-LCDLN) has 47,123 citations with a 98.6% out-of-service rate. This is the most severe enforcement we see: no license at all.
Medical Certificate violations (391.41APC) show 49,539 citations with a 97.1% out-of-service rate. These violations affect a driver's basic qualification to operate.
The distinction is clear: violations involving operating without a license or the wrong class trigger out-of-service rates above 97%. A restriction violation, by comparison, involves operating with a valid CDL but outside its conditions. That distinction may explain why we see zero citations in our records—the violation sits in a gray zone that inspectors may choose to address through other mechanisms.
How to avoid it
If you've been cited for 383.93, or if you want to ensure you never are, the actions are straightforward:
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Review your CDL restrictions every time you accept a load or assignment. Your restrictions are listed on the physical card and in your state's driver licensing system. Know them by heart. If you see an "A" restriction (automatic transmission only), you cannot operate a manual. If you see an "E" restriction (no air brakes), you cannot touch a truck with air brakes.
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Verify the vehicle type before you log in. Before your pre-trip inspection, confirm that the truck you're assigned matches your CDL class and restrictions. If dispatch assigns you a vehicle you're not licensed to operate, report it immediately and request a reassignment.
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If your restrictions have changed, request updated documentation. Some restrictions are temporary (e.g., during medical monitoring) or lifted after training. If you've completed air brake training or obtained a waiver, get written confirmation from your state DMV before assuming you can operate that equipment.
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Communicate with your carrier's safety department. Fleets manage driver licensing and vehicle assignments. If there's any confusion about what you can and cannot drive, flag it during onboarding or at the first assignment that feels unclear.
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Treat this violation as severe. Even though our data shows zero citations, the CSA severity weight of 6 and the 0.0% out-of-service rate in our records don't tell the whole story. Operating outside your CDL restrictions is a federal violation that puts you, your cargo, and the public at risk. Inspectors who cite this code are usually responding to a clear mismatch between your license and the vehicle you're operating.
The safest approach: never assume. Always verify.