What this is
What is a trailer inspection?
What is a trailer inspection?
It is a structured check of a trailer's coupling, running gear, body, load restraint and brakes, run before use and on a periodic schedule set for the fleet. It is built against FMCSA 396.11 and forms part of the Fleet and Driver Compliance programme.
What makes coupling and brake lines the knockout items?
A defective kingpin, fifth wheel plate or air line does not degrade the trailer's performance gradually the way a scuffed floor does — it can separate the trailer from the tractor or leave it without functioning brakes entirely. Those two items fail the whole inspection regardless of how well everything else scores.
How is this different from a Driver Vehicle Inspection Report?
A Driver Vehicle Inspection Report is the daily pre-trip and post-trip check a driver runs on the whole combination. This template is the deeper, scheduled inspection of the trailer specifically, run to a set frequency rather than every single trip.
Scope
When is a trailer inspection required?
This inspection is one step in a larger programme. Using it for work that belongs to a neighbouring template produces records that are hard to report on later.
Use this template when
- A trailer is due its inspection on the frequency set for that unit, or is being put into use for the first time
- The trailer has changed hands, been repaired, or had a defect reported since its last inspection
- You are running the Fleet and Driver Compliance programme and this is one of its steps
- A linked record needs this one to exist, because it links to the asset register
- A work order needs to be traced back to the inspection finding that raised it
Do not use it for
- Driver Vehicle Inspection Report, which is the daily pre-trip and post-trip check on the whole combination, not the scheduled trailer-specific inspection.
- Annual Vehicle Inspection, which is the yearly statutory inspection of the powered vehicle, run on a different cycle to this one.
- Reefer Unit Check, which checks refrigeration unit operation, fuel and temperature setpoint, not the trailer's structure or coupling.
- Load Securement Check, which checks the securing of a specific load on a specific trip, not the trailer's restraint equipment in general.
- Anything outside KnowFleet, which belongs in the workspace that owns that process
Compliance mapping
Which FMCSA 396.11 requirements does this satisfy?
The template is anchored to FMCSA 396.11 for the inspection record itself, with the specific mechanical checks drawn from Part 393's equipment standards.
| Clause | Requirement | Where it lands |
|---|---|---|
| 49 CFR 393.71 | Coupling devices and fifth wheel assemblies maintained and free from defect | Structure and running gear |
| 49 CFR 393.75 | Tyres free of defects that affect safe operation | Structure and running gear |
| 49 CFR 393.9 | Lamps and reflective devices operable | Structure and running gear |
| FMCSA 396.17 | Periodic inspection carried out at the interval set for the vehicle | Header |
| 49 CFR 393 Subpart I | Cargo securement devices adequate and rated for the load carried | Load restraint |
| FMCSA 396.11 | Written record of the inspection retained and any defect reported | Result |
What it does not cover
- Kingpin And Fifth Wheel Plate, which is marked Good from a glance rather than a hands-on wear check.
- Brakes And Air Lines, which is scored without the trailer being coupled up to test air pressure.
- Underrun Protection, which is assumed Present and sound because it usually is, not because it was inspected.
- Load Restraint Points Sound, which is passed without a single strap being tested under load.
- Door Seals Effective, which is marked Yes after a visual check with the doors already standing open.
Global
Trailer Inspection requirements by country
FMCSA sets the baseline for this template, but trailers cross borders and the roadworthiness regime that actually stops one at the roadside depends on where it is.
FMCSA 396.11 and 49 CFR Part 393
Requires a written inspection record and sets the equipment standards — coupling, brakes, lighting, cargo securement — that a trailer must meet to stay in service.
This template's field set exists to produce exactly the record 396.11 requires, in enough mechanical detail to satisfy 393's equipment standards.
CVSA North American Standard Out-of-Service Criteria
Sets the defect thresholds roadside inspectors use to place a trailer out of service on the spot, harmonised across the US, Canada and Mexico.
A defect this template scores as a knockout — coupling, brakes — is very likely the same defect that puts the trailer out of service at a CVSA roadside check.
Road Vehicles (Construction and Use) Regulations 1986
Sets the equipment and maintenance standard for trailers used on UK roads, enforced by DVSA at annual test and on the roadside.
A trailer used domestically in the UK should be assessed against this Regulation's brake, coupling and lighting requirements alongside, or instead of, the FMCSA basis if it never operates in the US.
How to complete it
How to complete a trailer inspection, step by step
Filling in the fields is mechanical. The judgement calls are what decide whether the finished inspection would survive someone else reading it cold.
Kingpin And Fifth Wheel Plate and Brakes And Air Lines need the trailer coupled and the brakes actually tested, not a walk-around. Decide and document the minimum physical steps required before a technician can answer either field.
Score Percent is a weighted average; it does not automatically fail the trailer for one bad coupling answer. The judgement call is wiring Trailer Fit For Service to the knockout fields directly, so a high average can never mask a genuine knockout failure.
Inspection Frequency is a free choice of Weekly, Monthly, Quarterly or Annual per trailer. A reefer trailer on daily multi-drop work needs a tighter interval than a rarely-used flatbed — setting every trailer to the same default frequency understates risk on the busiest units.
Fit For Food Transport sits next to Trailer Fit For Service as a separate judgement. A trailer can be roadworthy and still unfit to carry food if the lining is damaged or residue remains — the two fields should not be answered as if one implies the other.
What auditors find
Most common trailer inspection findings
The same six gaps turn up across trailer inspections that look complete on paper.
| Finding | Clause | What fixes it |
|---|---|---|
| Coupling checked visually without a load test | 49 CFR 393.71 | Require the trailer to be coupled and the kingpin engagement physically checked before Kingpin And Fifth Wheel Plate can be scored. |
| Brake air lines never pressure tested | 49 CFR 393 | Build a build-up-and-hold air test into the inspection procedure rather than a visual check for cracking alone. |
| Inspection frequency set generically, not by duty cycle | FMCSA 396.17 | Review Inspection Frequency against actual mileage or drop count per trailer, not a fleet-wide default. |
| Restraint Equipment Certified left at Unknown indefinitely | 49 CFR 393 Subpart I | Chase the certification document at the next scheduled inspection rather than carrying Unknown forward. |
| Trailer marked fit for service with an open Action Required | FMCSA 396.11 | Block Trailer Fit For Service at Yes while Action Required is Yes and the CAPA remains open. |
| No link kept to the haulier assessment for third party trailers | FMCSA 396.11 | Where the trailer belongs to a hired haulier, reference the Transport Provider Assessment rather than treating this inspection as the only check on the relationship. |
Case in point
Case in point: the trailer that passed on paper and failed at the scale
A curtainsider trailer clears its quarterly inspection with a comfortable score — tyres, lights, floor and restraint points all Good. The technician noted Brakes And Air Lines as Good too, based on a visual check for obvious cracking, without coupling the trailer to a tractor to test air pressure.
Two weeks later the trailer is placed out of service at a roadside weighbridge for a slow air leak that would have shown up under a five-minute pressure test. The inspection record looked complete and the score was high; the one field that mattered was answered from the wrong kind of check.
The template
The template, field by field
The form exactly as it installs. Every field, option, score and conditional rule is editable, and the links to other templates come with it.
5 sections
- Reference
- FLT-003
- Archetype
- Inspection
- Record ID
- INSP-2026-000
- Scoring
- Pass or fail with knockout items
- Direction
- High is good
- Singleton
- No
- Basis
- FMCSA 396.11
- Links
- Links Asset
- Tags
- Fleet, Inspection
- Sections
- 5
- Fields
- 52
- Follow up fields
- 3
- Repeating sections
- 0
- Links out
- 4
Header
12 fieldsInspection ID*
Auto sequence. Format TRI-2026-000.
The record's own ID. Other templates point at this value.
Status*
Drives who this goes to next.
- Planned2 pts
- In progress2 pts
- Complete3 pts
- Deferred0 pts
- Open0 pts
- Closed3 pts
- Overdue0 pts
Date and Time*
Completed By*
Site*
Site ID*
Format SITE-000.
Links to FDN-001 Site ID
Vehicle*
Asset ID*
Format AST-0000.
Links to FDN-002 Asset ID
Unit Number
The number painted on the door, which is what drivers actually use.
Trailer Type*
Refrigerated, curtainsider, box, flatbed or tanker.
Inspection Frequency*
Last Inspection Date
Structure and running gear
9 fieldsChassis Condition*
- Good3 pts
- Surface corrosion1 pt
- Structural damage0 pts
Kingpin And Fifth Wheel Plate*
- Good3 pts
- Wear noted1 pt
- Defective0 pts
Landing Legs*
- Good3 pts
- Stiff or damaged1 pt
- Defective0 pts
Axles And Suspension*
- Good3 pts
- Wear noted1 pt
- Defective0 pts
Brakes And Air Lines*
- Good3 pts
- Wear noted1 pt
- Defective0 pts
Tyres And Wheels*
- Pass3 pts
- Advisory2 pts
- Fail0 pts
Lighting And Wiring*
- All working3 pts
- Minor fault1 pt
- Multiple faults0 pts
Underrun Protection*
- Present and sound3 pts
- Damaged1 pt
- Missing0 pts
Number Plate And Markings*
- Legible3 pts
- Faded1 pt
- Missing0 pts
Body and load area
9 fieldsBody Structure Sound*
- Good3 pts
- Damage noted1 pt
- Defective0 pts
Insulation Intact
- Yes3 pts
- Partly1 pt
- No0 pts
Interior Lining Undamaged*
Damaged lining traps product debris and is a direct contamination route.
- Yes3 pts
- Minor damage1 pt
- Significant damage0 pts
Floor Condition*
- Good3 pts
- Fair1 pt
- Poor0 pts
Drainage Points Clear
- Yes3 pts
- Partly blocked1 pt
- Blocked0 pts
No Standing Water Or Residue*
- Clean and dry3 pts
- Some residue1 pt
- Standing water0 pts
Doors Operate Correctly*
- Yes3 pts
- Stiff1 pt
- Defective0 pts
Door Seals Effective*
- Yes3 pts
- Worn1 pt
- Failed0 pts
Locking And Security Seals Fitted*
- Yes3 pts
- Partly1 pt
- No0 pts
Load restraint
5 fieldsLoad Restraint Points Sound*
- All sound3 pts
- Some damaged1 pt
- Many damaged0 pts
Curtains And Straps Condition
- Good3 pts
- Worn1 pt
- Damaged0 pts
Load Bars And Rails Present*
- Sufficient3 pts
- Limited1 pt
- None0 pts
Rated Capacity Marked*
- Yes3 pts
- Faded1 pt
- Missing0 pts
Restraint Equipment Certified
- Yes3 pts
- Unknown1 pt
- No0 pts
Result
17 fieldsItems Assessed*
Excludes anything marked N/A.
Items Failed*
Score Percent*
Calculated on submission. High is good. N/A items leave the denominator.
Result Band*
- Pass3 pts
- Caution1 pt
- Fail0 pts
Completeness Percent*
How much of the template was actually answered. A high score on a half completed form is not a high score.
Trailer Fit For Service*
- Yes3 pts
- With restriction1 pt
- No0 pts
Fit For Food Transport*
- Yes3 pts
- After cleaning1 pt
- No0 pts
Work Order ID
Links to MNT-002 Work Order ID
Action Required*
Raise the action record, then enter its reference here.
- No2 pts
- Yes0 pts
Priority
- High0 pts
- Medium1 pt
- Low3 pts
CAPA ID
Format CAPA-2026-00000.
Links to FDN-014 CAPA ID
Action Owner
Next Due*
Inspector*
Signature*
Fleet Manager*
Second Signature*
FLT-003 · record IDs look like INSP-2026-000 · Links Asset
Open in KnowellaRun it with agents
From a document you fill in to a programme that runs itself
The form is the easy part. Keeping it current, routing it to the right owner and holding the evidence together is the work that actually slips.
Holds the trailer inspection history against the asset register, flags when a unit is due its next inspection, and keeps knockout failures visible until they are closed.
Turns a failed inspection into a work order automatically, so a defective coupling or brake line does not sit unresolved between the inspection record and the repair.
Checks a trailer's fit-for-service status before it is scheduled onto a load, so a knockout failure cannot quietly get booked into a tender.
Coordinates the crew, rolls completion and exceptions into one view, and holds every write for your approval before it touches a record.
This template lives in KnowFleet — fleet and transport. Drivers, vehicles, hours, cargo securement and operator licence compliance.
Meet KnowFleet→Glossary
Trailer Inspection definitions and key terms
- Fifth wheel
- The coupling plate on the tractor that the trailer's kingpin locks into. Wear here is a structural safety issue, not cosmetic.
- Kingpin
- The pin on the trailer's underside that engages the fifth wheel. A worn or damaged kingpin risks the trailer separating from the tractor in transit.
- Underrun protection
- The guard fitted to a trailer's rear and sides to stop a smaller vehicle sliding underneath it in a collision. Its absence is a knockout-level safety gap.
- Cargo securement
- The straps, bars, rails and rated fixings used to stop a load shifting in transit, governed in the US by 49 CFR Part 393 Subpart I.
- Knockout item
- A field whose failing answer fails the whole inspection outright, regardless of how the rest of the form scores. Here, coupling and brake lines.
FAQ
Frequently asked questions about trailer inspection
Does a high Score Percent mean the trailer is safe to use?+
Not on its own. Score Percent is a weighted average across 52 fields; Trailer Fit For Service should be governed by the knockout items specifically, not by the average alone.
Who should carry out this inspection?+
A driver can complete routine checks, but coupling and brake items are better handled by a technician with the equipment to test air pressure properly, especially at the longer periodic intervals.
What happens if a knockout item fails?+
Action Required should be set to Yes, a work order or CAPA raised, and Trailer Fit For Service set to No or With restriction until the defect is corrected and re-checked.
Does inspection frequency need to be the same for every trailer?+
No. Weekly, Monthly, Quarterly and Annual are all offered because duty cycle varies — a trailer in daily multi-drop use should not sit on the same schedule as one used occasionally.
How does this relate to the Fleet and Driver Compliance programme?+
It is one of the core inspection records in that programme, sitting alongside Annual Vehicle Inspection and Driver Vehicle Inspection Report to build an operator licence position that would hold up at audit.
Can the field set or scoring be changed?+
Yes. Every field, option, score and conditional rule is editable, and the link to the asset register comes with it. Most fleets run it as installed for a full inspection cycle before adjusting.
Keep going
Related templates and programmes
Industries this is written for
Programmes this belongs to
Used together in Fleet and Driver Compliance
Transport Provider Assessment
Assesses a haulier for licensing, driver management, vehicle standards, temperature capability and load security
Driver Vehicle Inspection Report
The pre-trip and post-trip inspection a driver completes on a commercial vehicle
Annual Vehicle Inspection
The yearly statutory inspection of a commercial vehicle
Reefer Unit Check
Checks refrigeration unit operation, fuel, temperature setpoint and alarm history
Vehicle Defect Report
Reports a defect found on a vehicle at any time, not just during a scheduled inspection
Roadside Inspection Record
Records a roadside inspection by an enforcement officer, including any violations and out of service orders
More in Vehicle Inspections
Driver Vehicle Inspection Report
The pre-trip and post-trip inspection a driver completes on a commercial vehicle
Annual Vehicle Inspection
The yearly statutory inspection of a commercial vehicle
Reefer Unit Check
Checks refrigeration unit operation, fuel, temperature setpoint and alarm history
Vehicle Defect Report
Reports a defect found on a vehicle at any time, not just during a scheduled inspection
Roadside Inspection Record
Records a roadside inspection by an enforcement officer, including any violations and out of service orders
Tyre Condition Record
Records tyre tread depth, pressure and damage across the vehicle
Written and reviewed by
Siddarth Singh
Founder & Chief Executive Officer, Knowella
Certified Safety Professional and industrial and systems engineer with more than a decade inside food supply chain, freight and manufacturing operations. This page was written against the current text of the standards it cites, not against secondary summaries of them.
- Certified Safety Professional (CSP), Board of Certified Safety Professionals
- MBA, University of Chicago Booth School of Business
- MS and BS, The Ohio State University, Industrial and Systems Engineering
- Six Sigma Black Belt
Sources and last review. Reviewed 16 August 2026 against:
- FMCSA 396.11 — Driver vehicle inspection report(s)
- FMCSA 396.17 — Periodic inspection
- 49 CFR 393.71, 393.75, 393.9 and Subpart I — Equipment and cargo securement standards
- Road Vehicles (Construction and Use) Regulations 1986 (UK)
This page is general guidance, not legal advice. Confirm requirements with your jurisdiction’s regulator.