FMCSA Out of Service Risk Assessment
Free ToolAnswer 15 questions about your vehicle's current condition across brakes, tires, lights, steering, coupling devices, and fuel system. Instantly identify which defects will trigger an out-of-service order at a DOT roadside inspection — before the inspector does.
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What Triggers an FMCSA Out-of-Service Order — The Complete 2026 List
An out-of-service (OOS) order is issued by a CVSA-certified inspector when a vehicle defect meets or exceeds thresholds defined in the North American Standard Out-of-Service Criteria, which is updated annually and aligns with 49 CFR Parts 393 and 396. Unlike a warning, an OOS order means the vehicle cannot legally move under its own power until the defect is corrected and the OOS order is cleared.
The following table lists the vehicle defects most commonly resulting in OOS orders at Level I roadside inspections:
| Defect | CFR Citation | OOS Level | Severity |
|---|---|---|---|
| Any audible air brake leak | 49 CFR §393.45 | Immediate OOS | Critical |
| Brake lining below minimum thickness (steer axle) | 49 CFR §393.47(d) | Immediate OOS | Critical |
| Brake pushrod stroke beyond readjustment limit | 49 CFR §393.47(e) | Immediate OOS | Critical |
| Tire with exposed ply or fabric cord | 49 CFR §393.75(a) | Immediate OOS | Critical |
| Steering axle tire below 4/32" tread | 49 CFR §393.75(c) | Immediate OOS | Critical |
| Any fuel leak in the system | 49 CFR §393.65 | Immediate OOS | Critical |
| Fifth wheel locking jaws not engaged | 49 CFR §393.70 | Immediate OOS | Critical |
| Broken or missing steering component | 49 CFR §393.209 | Immediate OOS | Critical |
| Inoperable stop lamp (brake light) | 49 CFR §393.25 | OOS | High |
| Missing or broken safety chain on combination vehicle | 49 CFR §393.71 | OOS | High |
| Drive axle tire below 2/32" tread | 49 CFR §393.75(c) | OOS | High |
| Multiple inoperable clearance/marker lights | 49 CFR §393.11 | Warning | Medium |
Source: FMCSA 49 CFR Parts 393 and 396; CVSA North American Standard Out-of-Service Criteria, current edition. "Immediate OOS" = zero inspector discretion.
Vehicle maintenance compliance is one of seven FMCSA CSA BASICs. To maintain a complete compliance posture, also check your fleet's annual DOT inspection due dates — operating a vehicle with an expired annual inspection sticker is a separate OOS trigger under 49 CFR §396.17.
The 6 Vehicle Systems Inspected in Every CVSA Level I — What Inspectors Actually Look For
A CVSA Level I inspection is systematic — not random. Inspectors work through the same 6 vehicle systems in approximately the same order every time. Understanding what they check in each system lets you prioritize your pre-dispatch inspection accordingly.
Brakes
49 CFR §393.45–393.55
3 brake questions covering air leaks, lining thickness, and pushrod stroke adjustment. Brake violations account for approximately 43% of all vehicle OOS orders nationally.
Tires
49 CFR §393.75
3 tire questions covering tread depth by axle position, sidewall condition, and inflation. Tire violations are the second-most-common OOS trigger after brakes.
Lights
49 CFR §393.11–393.33
3 lighting questions covering headlights, stop lamps, and clearance/marker lights. Lighting violations rarely cause immediate OOS alone but stack with other defects.
Steering
49 CFR §393.201–393.213
3 steering questions covering freeplay, power steering leaks, and component integrity. A single broken steering component is an automatic OOS regardless of other vehicle condition.
Coupling Devices
49 CFR §393.70–393.71
3 coupling questions covering fifth wheel engagement, safety chains, and kingpin wear. Coupling failures are catastrophic — inspectors treat these as zero-tolerance items.
Fuel System
49 CFR §393.65–393.67
3 fuel system questions covering leaks, tank security, and line routing. Any fuel leak anywhere in the system is an automatic OOS — no exceptions.
DOT Roadside Inspection Statistics — Why This Matters to Your Bottom Line
These are not hypothetical risks. The CVSA publishes inspection data annually showing the real-world frequency of OOS orders and the financial exposure carriers face:
~3.5M
Commercial vehicle roadside inspections per year in North America
~22%
Percentage of inspected vehicles placed out of service
43%
Of all vehicle OOS orders involve brake defects
$1,500+
Average daily revenue loss when a truck is placed OOS
The math: A single OOS order on a truck running 250 days per year at $1,500/day revenue represents a 0.4% annual revenue loss — plus the cascading CSA score damage that increases future inspection frequency, potentially triggering 3–5 more inspections in the same 24-month window.
Your Legal Pre-Trip Inspection Obligation — 49 CFR §396.13
The pre-trip inspection is not optional. Under 49 CFR §396.13, before driving a commercial motor vehicle, the driver must:
Be satisfied that the vehicle is in safe operating condition
49 CFR §396.13(a)
Review the last driver vehicle inspection report (DVIR) if one was prepared for that vehicle
49 CFR §396.13(b)
Sign the DVIR to acknowledge review and confirm any noted defects have been repaired or are not safety-affecting
49 CFR §396.13(c)
Additionally, 49 CFR §396.11 requires the driver to prepare a DVIR at the end of every day, reporting any defects or deficiencies that would affect safe operation. Failure to prepare a DVIR when required is itself a violation — separate from any underlying vehicle defect.
Critical for audits: An inspector finding a defect that a driver clearly should have identified during pre-trip inspection can issue a §396.13 violation on top of the vehicle defect violation — doubling the CSA score impact. Document your inspections.
Vehicle OOS risk is separate from driver compliance risk. A truck in perfect mechanical condition can still be a compliance liability if the driver's DOT medical certificate has expired or their CDL is lapsed — both of which result in an immediate driver OOS order.
How Vehicle Defects Damage Your CSA Vehicle Maintenance BASIC Score
Every violation recorded at a roadside inspection feeds into FMCSA's Safety Measurement System (SMS) under the Vehicle Maintenance BASIC. Understanding how violations are weighted explains why preventing OOS orders is more cost-effective than clearing them after the fact.
Severity weight 10
Assigned to critical OOS violations (brakes, fuel leaks, fifth wheel)
24 months
How long violations remain on your CSA record (rolling window)
65%+
Vehicle Maintenance BASIC threshold for FMCSA warning letter or audit
2×
Score multiplier applied when a driver receives an OOS order at inspection
The Vehicle Maintenance BASIC compares your carrier's inspection performance against other carriers of similar size operating in similar conditions. A carrier whose score crosses the 65% threshold will receive a FMCSA warning letter. Continued elevation triggers a compliance review or targeted audit. Carriers under audit face penalties, increased bond requirements, and in severe cases, an Operations OOS order that halts all operations.
Vehicle maintenance violations compound with violations in other BASICs. Use our Driver Qualification File Checker to ensure your DQ files are audit-ready, and verify your drug and alcohol testing program meets minimums with our Random Drug Testing Calculator — deficiencies across multiple BASICs accelerate FMCSA intervention timelines significantly.
About This OOS Risk Assessment Tool
Built by TruckComplianceHQ, a DOT compliance software company. The assessment questions and scoring weights are based on 49 CFR Parts 393 and 396, and the CVSA North American Standard Out-of-Service Criteria. OOS weight scores (1–10) reflect the probability that a given defect will result in an OOS order at a CVSA Level I inspection based on published violation frequency data. Browse the full free DOT compliance tools library for driver qualification, hours of service, drug testing, and annual inspection tracking.
This tool is for informational and pre-inspection planning purposes only. It does not substitute for a physical inspection by a qualified mechanic or CVSA-certified inspector. For official OOS criteria, refer to the sources below.
FMCSA Out of Service Criteria — Frequently Asked Questions
What triggers an immediate out-of-service order at a DOT roadside inspection?
Under CVSA North American Standard out-of-service criteria, specific vehicle defects trigger an immediate OOS order, meaning the vehicle cannot move until the defect is corrected. The most common automatic OOS triggers include: any audible air brake leak (49 CFR §393.45), a brake chamber pushrod stroke exceeding the readjustment limit on a steering axle (49 CFR §393.47), any tire with exposed ply or fabric cord (49 CFR §393.75), any fuel system leak (49 CFR §393.65), fifth wheel locking jaws not properly engaged around the kingpin (49 CFR §393.70), and any cracked, broken, or missing steering component (49 CFR §393.209). These are zero-tolerance items — the inspector has no discretion.
How does an out-of-service order affect my CSA score?
An OOS order during a roadside inspection generates a violation that is recorded in FMCSA's SMS (Safety Measurement System) under the Vehicle Maintenance BASIC. Each violation carries severity weights ranging from 1 to 10 points depending on the defect type, with OOS-level violations receiving the highest weights. These points remain on the carrier's CSA record for 24 months on a rolling basis. Carriers whose Vehicle Maintenance BASIC score crosses FMCSA's intervention threshold (65% for most carrier sizes) become targets for compliance reviews, targeted roadside inspections, and in severe cases, an Operations Out-of-Service order that shuts down the entire carrier.
What is a CVSA Level I inspection?
A CVSA Level I (North American Standard Inspection) is the most comprehensive roadside inspection and the one most likely to result in OOS orders. It includes a 37-step driver examination and a thorough inspection of the vehicle covering: brake systems, coupling devices, exhaust systems, fuel systems, lights, steering mechanisms, suspension, tires, wheels and rims, windshield wipers, and the frame. Level I inspections are performed by certified inspectors and typically take 45–90 minutes. Approximately 30–35% of vehicles placed in Level I inspections receive an OOS order, according to CVSA annual inspection data.
What is the minimum brake lining thickness to pass a DOT inspection?
Under 49 CFR §393.47(d), brake lining thickness minimums depend on axle position. For steering axle brakes, the minimum is 1/4 inch (6.4mm) for drum brakes. For all other axles, the minimum is 1/8 inch (3.2mm) for drum brakes. Disc brake pads must be at least 1/16 inch (1.6mm) for all axle positions. Additionally, brake linings must not be saturated with oil or grease, must not be cracked or loose, and must not be contaminated in a way that affects braking capability. A single brake below minimum thickness on a steering axle is sufficient for an OOS order.
What are the tire tread depth requirements for DOT roadside inspections?
Under 49 CFR §393.75(c), steering axle tires must have at least 4/32 inch (3.2mm) of tread depth measured in any major tread groove. All other tire positions (drive axles, trailer axles) must have at least 2/32 inch (1.6mm) of tread depth. A tire below these minimums will result in an OOS order. Additionally, any tire with exposed ply or fabric, a cut or snag that exposes ply or cord, a bulge or knot caused by tread or sidewall separation, or flat or noticeably under-inflated condition will also trigger an OOS order regardless of tread depth.
How do I fix an air brake out-of-adjustment violation?
Brake adjustment must be corrected by a qualified brake mechanic before the vehicle can legally operate. For s-cam drum brakes, adjustment involves backing off brake slack adjusters to verify stroke, then using a slack adjuster tool to bring the pushrod stroke within the readjustment limit specified in 49 CFR §393.47(e) — limits vary by brake chamber type and size. Automatic slack adjusters (ASAs) should self-adjust, so if an ASA-equipped brake is out of adjustment, the ASA itself likely needs replacement rather than manual adjustment. After correction, a brake performance test should be conducted before returning the vehicle to service.
Does a fuel leak always result in an out-of-service order?
Yes. Under CVSA North American Standard OOS criteria aligned with 49 CFR §393.65, any fuel leak — regardless of severity — is an automatic OOS item for CMVs operating in interstate commerce. This includes leaks from the fuel tank, fuel lines, fittings, or fuel pump. Even a slow drip is sufficient. The rationale is fire risk: fuel on or near hot exhaust components creates an immediate fire hazard. The vehicle must be towed or the leak repaired on-site before it can legally move under its own power. Fuel cap absence or a loose fuel cap may result in a warning or violation but is typically not an automatic OOS unless fuel is actively spilling.
How much does a DOT out-of-service violation cost a trucking company?
The true cost of an OOS violation has three components. First, the direct revenue loss: a driver placed OOS during a trip loses that day's load, often costing $500–$2,000 depending on the freight. Second, towing and repair costs if the defect cannot be fixed roadside, which can range from $500 to $5,000+. Third, the CSA score impact: OOS violations receive severity weights of 8–10 in the Vehicle Maintenance BASIC, which can push a carrier toward FMCSA's intervention threshold, triggering increased inspections that compound revenue losses over the following 24 months. Civil penalties for specific Part 393 violations can reach $16,000 per violation for egregious cases.
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