How to use this checklist
Appendix A to Part 396 is titled "Minimum Periodic Inspection Standards." It opens with one sentence that sets the logic: a vehicle does not pass an inspection if it has one of the listed defects or deficiencies. Your checklist is therefore a list of reject conditions, grouped into 15 areas. This page summarizes those areas and the points that most often decide a pass or a fail. It does not reproduce every line of the appendix, so keep the current eCFR text at the inspection station and use it whenever a reading is close.
Inspect each unit separately. Section 396.17(a) says a tractor, semitrailer, full trailer and converter dolly in a combination must each be inspected.
Before you start
- Confirm the inspector meets 49 CFR 396.19 (see who can perform a DOT annual inspection).
- Record carrier name, unit number, VIN, make, year and odometer or hours.
- Park on level ground, chock wheels, and have a brake stroke gauge or ruler, tread depth gauge, and lighting for under-vehicle work.
- For air brakes, stroke is measured with the engine off and reservoir pressure of 80 to 90 psi with brakes fully applied, as stated in Appendix A.
1. Brake system
Service brakes. Reject if: - no braking action on any axle required to have brakes; - missing or broken components: shoes, lining, pads, springs, anchor pins, spiders, cam rollers, push rods, air chamber mounting bolts; - loose components, including air chambers, spiders and cam shaft support brackets; - audible air leak at a brake chamber (for example a ruptured diaphragm or loose clamp); - pushrod stroke beyond the readjustment limit for the chamber type in the Appendix A tables and 49 CFR 393.47(e) (for unlisted actuators, beyond 80 percent of the rated stroke or the limit marked by the manufacturer); - lining or pad not firmly attached, or saturated with oil, grease or brake fluid; - lining thickness on non-steering axles less than 1/4 inch at the shoe center for air drum brakes, 1/16 inch or less for hydraulic and electric drum brakes, or less than 1/8 inch for air disc brakes; - lining on steering axles less than 1/4 inch at the shoe center for drum brakes, less than 1/8 inch for air disc brakes, or 1/16 inch or less for hydraulic disc and electric brakes; - a missing brake on any axle required to have brakes; - a mismatch across a power unit steering axle in air chamber size or slack adjuster length.
Parking brake. Reject if no brakes apply when the parking brake control is actuated.
Drums and rotors. Reject if there is an external crack that opens on application (not short hairline heat checks), or any portion missing or about to fall away.
Hoses and tubing. Reject if damage extends through the outer reinforcement ply, there is bulging or swelling under pressure, audible leaks, or improper joints or splices, plus the other hose and tubing conditions Appendix A lists.
Appendix A also covers the low pressure warning device, tractor protection valve, air compressor, electric brakes, hydraulic brakes and vacuum systems. Check each system the vehicle has.
2. Coupling devices
For fifth wheels, reject missing or ineffective mounting fasteners, movement between mounting parts, more than 3/8 inch movement at the pivot bracket pin or between slider bracket and base, missing slider stops, more than 1/2 inch horizontal movement between the upper and lower halves, an operating handle not closed or locked, a kingpin not properly engaged, and locking parts missing, broken or deformed. Appendix A also covers pintle hooks, drawbars and towbars, and safety devices.
3. Exhaust system
Reject an exhaust leak forward of or directly below the driver or sleeper compartment, and any exhaust part located where it is likely to burn, char or damage wiring, the fuel supply or a combustible part. Buses have added discharge limits.
4. Fuel system
Reject a visible leak at any point, a missing filler cap, and a tank not securely attached because of loose, broken or missing mounting bolts or brackets.
5. Lighting devices
All lighting devices and reflectors required by Part 393 must be operable.
6. Safe loading
Reject a condition in which the spare tire, load or dunnage can fall onto the roadway, a missing front-end structure where one is required, and cracked, broken, loose or missing container securement devices on intermodal chassis.
7. Steering mechanism
Check steering wheel free play against the limits in Appendix A (for example, on a 20 inch wheel, 2 1/2 inches for manual steering and 5 1/4 inches for power steering, with the engine running on power steering), steering column U-bolts, universal joints and wheel security, cracks or obvious welded repairs on the front axle beam and steering components, loose or missing gear box mounting bolts, pitman arm looseness, a loose auxiliary power assist cylinder, ball and socket joint movement, loose tie rod and drag link clamps or threaded joints, and loose or missing nuts.
8. Suspension
Look for U-bolts, spring hangers or other axle positioning parts that are cracked, broken, loose or missing and let the axle shift from its normal position; broken or missing leaves, a broken main leaf, a broken coil or torsion bar spring, a missing rubber spring, displaced leaves that could contact a tire, rim, drum or frame, and a deflated air suspension; and torque, radius or tracking components that are cracked, loose, broken or missing (loose bushings in torque or track rods excepted).
9. Frame
Reject for any cracked, broken, loose or sagging frame member and for loose or missing frame fasteners, plus the other frame conditions listed in Appendix A.
10. Tires
- Steering axle tires on a power unit. Reject if tread is less than 4/32 inch at any point on a major tread groove; ply or belt material is exposed through the tread or sidewall; there is tread or sidewall separation; a cut exposes ply or belt; the tire is labeled "Not for Highway Use"; bias and radial tires are mixed on the same axle; or the tire is regrooved (except in the urban or suburban service exception in 393.75(e)), among the other listed items.
- All other tires. Reject if the weight carried exceeds the tire load limit (including from low pressure); the tire is flat or has a noticeable leak; ply or belt is exposed; there is separation; a cut exposes ply or belt; it contacts any part of the vehicle or its mate; it is marked "Not for highway use"; or tread is less than 2/32 inch on a major groove.
- Speed restricted tires are a reject unless specifically designated by the motor carrier.
11. Wheels and rims
Reject for bent, broken, cracked, improperly seated, sprung or mismatched lock or side rings; cracked or broken wheels or rims or elongated bolt holes; loose, missing, broken, cracked, stripped or otherwise ineffective fasteners; cracked welds attaching a disc to a rim or a tubeless demountable rim to its adapter; and welded repairs on steering axle aluminum wheels or (other than the disc to rim attachment) steering axle steel disc wheels.
12. Windshield glazing
Outside a 2 inch top border, 1 inch side borders and the area below the top of the steering wheel, reject any crack, discoloration or vision reducing matter, except factory tinting, a single crack not over 1/4 inch wide that no other crack intersects, a damaged area not over 3/4 inch in diameter that is at least 3 inches from any other, and labels allowed by 393.60.
13. Windshield wipers
Any power unit with an inoperative wiper, or with missing or damaged parts that make a wiper ineffective, fails.
14. Motorcoach seats
For buses, check that passenger seats are securely fastened to the vehicle structure.
15. Rear impact guard
For trailers and semitrailers with a GVWR of 10,001 pounds or more built on or after January 26, 1998, reject a missing or insecurely attached guard, a horizontal member more than 22 inches above the ground or more than 12 inches forward of the rear, one that does not reach within 4 inches of each side, or one less than 4 inches tall. Older vehicles have different limits in Appendix A.
After the inspection
- Write the report required by 49 CFR 396.21: inspector, carrier, date, vehicle, components inspected, results including anything that failed, and a certification that the inspection is accurate and complete.
- Put documentation on the vehicle as 396.17(c) requires: the report, or a sticker or decal with the date, the name and address of the entity holding the report, identification of the vehicle if not clearly marked, and a certification that it passed.
- If the vehicle failed, quote the repairs, get approval and reinspect the failed items before you certify a pass.
- Keep the report at least fourteen months (396.21).
MetaFleet can turn your own inspection PDF into a digital inspection that technicians complete on a phone, keep the result with the unit, and schedule the next inspection as a reminder. See inspections and DVIRs or get a walkthrough.
Related pages
- How to do a DOT annual inspection, step by step
- 49 CFR 396 explained for shops
- Out-of-service criteria, which are a separate standard used at roadside
This checklist summarizes Appendix A to Part 396 as shown on eCFR on October 30, 2026. It is a working aid, not legal advice. When a measurement is close, the current eCFR text controls.