DOT compliance isn't optional and the rules change yearly. Here's a clean, current map of every audit-able touchpoint, with the deadlines that matter.
A single missed quarterly IFTA or expired medical card can trigger a full audit. Most fleets don't fail compliance from negligence — they fail from one outdated tracker.
Any vehicle 10,001+ lbs GVWR crossing state lines needs a USDOT number. Hazmat or 9+ passenger requires MC authority too. Biennial Update (MCS-150) is the most-missed: due every 24 months on the month matching the last digit of your DOT number.
Every CDL driver needs a DQ file with: application, MVR (annual), road test, medical card (max 24 months), annual review of driving record, and drug/alcohol pre-employment + random results. Missing one line = $1,000+ violation.
11-hour driving / 14-hour on-duty / 70-hour 8-day rule for property carriers. ELD required since 2019 with very narrow exemptions. Keep 6 months of logs on file and supporting docs (fuel receipts, BOLs) for 6 months.
Pre- and post-trip DVIRs are mandatory and the #1 thing an inspector asks for. Train drivers to do a real walk-around, document defects, and never roll a truck with a brake adjustment more than 1/4" out.
If you operate 26,001+ lb across state lines, you owe IFTA quarterly fuel-tax reports and IRP apportioned plates. Late IFTA = $50 minimum + 10% of tax owed. Use telematics or fuel-card data — don't reconstruct from receipts.
Pre-employment, random (50% drug / 10% alcohol annual rate as of 2026), post-accident, reasonable suspicion, return-to-duty. Use a C/TPA — don't run the program in-house.
Brake adjustment violations remain ~30% of out-of-service orders. Form 396 inspection records and hours-of-service errors are next.
Every 24 months, in the month matching the last digit of your USDOT number. Miss it and your DOT number is deactivated.
Many states require it intrastate too — TX, NY, CA, FL among them. Always check state-level requirements; federal threshold is interstate + 10,001 lb GVWR.
Three triggers: complaint, post-accident, or random selection driven by CSA scores. Anything above 65 on a BASIC dramatically raises audit odds.