What 391.11B4-DEN means in plain language
This citation means you were operating a commercial motor vehicle (CMV) without the proper endorsements your license requires, or you violated a restriction attached to your license. Endorsements are the special qualifications a state adds to your commercial driver's license (CDL)—for hazardous materials, passenger transport, or double/triple trailers, for example. Restrictions limit what you can do: some drivers are restricted to daylight hours, automatic transmissions, or vehicles under a certain weight.
If you received this citation, an inspector determined that either (1) you lacked an endorsement the vehicle or cargo required, or (2) you violated a stated restriction on your current license. This is fundamentally different from not holding a CDL at all—you have a license, but it's not matched to the work you were doing.
The state that issued your license is responsible for tracking and enforcing these endorsements and restrictions. When FMCSA roadside inspectors find a mismatch, they cite it under 391.11B4-DEN.
What our enforcement data actually shows
Across our 13 million roadside inspection records, 391.11B4-DEN has generated 1,442 all-time citations. Over the last 12 months, we recorded 654 citations; in the last 90 days, 118.
The critical number: 98.0% of drivers cited under this code were placed out of service. That is far above the all-FMCSR average OOS rate of 31.4%. Out-of-service means you were removed from duty on the spot. Of the 1,413 drivers placed OOS for this violation, only 29 were not.
This code ranks #622 out of 3,036 FMCSR codes by citation volume, meaning it's not the most common violation inspectors see, but it carries extremely high enforcement consequences when it is found.
Monthly citations have fluctuated between 34 and 81 over the past year, with a spike in May 2025 (81 citations, 80 OOS). Current enforcement activity remains steady.
Who gets cited most
Our data over the last 180 days shows three states account for the majority of 391.11B4-DEN citations:
- New Mexico: 118 citations, 100.0% placed out of service
- Iowa: 49 citations, 100.0% placed out of service
- North Carolina: 46 citations, 100.0% placed out of service
All three states enforce this code with near-perfect OOS consistency. Illinois follows with 31 citations and a 93.5% OOS rate—a small variation, but the pattern is clear: inspection officers treat endorsement and restriction violations as non-negotiable safety issues.
All-time, our records show fleets such as Federal Express Corporation (86,876 USDOT) with 21 citations under this code. Swift Transportation Co of Arizona (54,283 USDOT) appears with 8 citations. Large carriers attract attention proportionally to their fleet size, but the high OOS rate applies universally regardless of carrier.
How severe is this compared to similar codes
Endorsement violations sit in the Driver Fitness category alongside several other license-related offenses. Our data shows stark differences in enforcement intensity:
- 383.23(a)(2) (operating the wrong class of CMV): 50,385 all-time citations, 98.4% OOS rate
- 383.23A2-LCDLN (operating without a valid CDL): 47,123 citations, 98.6% OOS rate
- 391.11B2-Q (English language proficiency requirement): 23,688 citations, 65.2% OOS rate
Your violation sits in the company of the most aggressively enforced license defects. The 98.0% OOS rate for 391.11B4-DEN is functionally identical to the top two peer codes and substantially higher than language-proficiency violations. This is because endorsements and restrictions exist to protect public safety—hazmat endorsements, for example, ensure drivers understand explosive cargo; passenger endorsements require specific training.
How to avoid it
The foundation is simple: verify your license endorsements and restrictions match your assignment before you accept a load or enter a vehicle.
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Before dispatch: Request a copy of the routing assignment and cargo details. Cross-check against your CDL. If the load requires hazmat, doubles, or passenger transport, confirm you hold the endorsement. If you hold any restrictions (daylight-only, automatic transmission, no air brakes), ensure the vehicle and route comply.
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Examine your physical license card. Look at the back. Many drivers are unaware of restrictions they carry. Common ones are marked with codes like "K" (no air brakes), "L" (vehicles under certain weight), or "E" (automatic transmission only).
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Report mismatches immediately. If your dispatcher assigns you cargo or a vehicle that exceeds your endorsements or violates your restrictions, escalate before you depart. Inspect notes show that drivers operating without proper endorsements often appear alongside missing equipment or documentation (396.17C appears in 11 co-occurring inspections) and documentation failures (383.23A2 co-occurs in 11 inspections). These patterns suggest haste or confusion about assignment details.
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Schedule license renewal well in advance. Our data shows 11 inspections where 391.11B4-DEN co-occurred with 383.23A2 (operating without a CDL). This may reflect expired or suspended licenses. Renew before expiration.
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If you operate older vehicle makes (Freightliners, Kenworths, Utilities, Volvos, and Internationals account for over 1,000 citations combined), ensure your license matches that equipment class. Older tractors may require endorsements that newer models don't.
The data is unambiguous: this violation almost always results in removal from service. Prevention—a single five-minute check of your license against your assignment—is infinitely cheaper than downtime, a failed inspection, and potential CSA consequences.