What is a USDOT number?
A USDOT number is the identifier FMCSA assigns to a motor carrier — the company, not the truck. It's used to track your safety record, inspections and audits. It goes on the power unit as “USDOT” followed by the number, both sides, in a color that contrasts with the paint (49 CFR §390.21).
Do I need a USDOT number?
Federally, yes if you operate in interstate commerce a vehicle over 10,001 lbs GVWR/GCWR, carry 9+ passengers for hire (or 16+ not for hire), or haul placarded hazmat. Many states also require one for intrastate-only trucks over their own thresholds. The free compliance check applies both layers to your state.
Do I need an MC number on my truck?
Not by federal rule — 49 CFR §390.21 requires only your legal or trade name and USDOT number on the truck. If you have MC operating authority many for-hire carriers add it because brokers, shippers and some states ask to see it. It's a common addition, not a required marking.
What is GVWR, and do I put it on the truck?
GVWR is the manufacturer's maximum loaded weight for the vehicle — it's on the driver-door-jamb sticker. Some states require the GVW/GVWR (or your registered weight) displayed on commercial vehicles; federal rule does not. The compliance check tells you if your state does.
What size should my USDOT number be?
Federal rule sets no letter height — it requires the marking to be readable in daylight from 50 feet and to contrast with the truck. 2″ is the common size on pickups and vans; we recommend 3″–4″ on box trucks, semis and buses. A few states set explicit minimums (Colorado and West Virginia 3″, Hawaii 2.5″); the check applies those automatically.
Where do DOT numbers go on a truck?
Both sides of the power unit — the cab doors are standard because they're flat, vertical and visible from the side. Name on top, USDOT below, then MC/GVW/state number if you run them. Trailers only need markings if a state rule or your operation requires them.
Do I need reflective decals?
Not for the marking rules — federal and state marking rules are about legibility from 50 feet in daylight, and standard high-contrast vinyl meets that. Reflective vinyl is a visibility upgrade for night operations; it's separate from the retro-reflective conspicuity tape required on trailers (49 CFR §393.11), which is a tape product, not lettering.
Are magnetic USDOT signs legal?
Yes — the rules say the marking must be displayed and legible; they don't say how it's attached, and FMCSA guidance allows removable devices as long as the marking is displayed while the vehicle is operated. Magnets suit leased, rented and rotating trucks. Rented trucks over 30 days generally need to be marked as yours.
What's the difference between USDOT and MC numbers?
USDOT identifies the carrier for safety purposes; MC (docket) numbers are operating authority for for-hire interstate carriers. You can have a USDOT without an MC (private carriers), and the USDOT is the one that must be on the truck.
What markings do intrastate carriers need?
It depends entirely on the state. Some adopt the federal rules for intrastate trucks over 10,001 lbs (name + USDOT), some start at 26,001 lbs, some add their own number (CA#, TxDMV, PUCO, ILL.C.C.), and a few set letter heights. Our state pages list each with the citation and verification date.
How do I replace old truck lettering?
Heat the old vinyl with a hair dryer or heat gun, lift a corner and pull low and slow, then remove adhesive with a citrus remover and clean with alcohol. New decals go on the clean, dry panel. If the old lettering left a “ghost” in the paint, size the new decals to cover it — send us a photo and we'll match the size.
How long do vinyl decals last?
We cut on commercial-grade outdoor vinyl rated 5+ years in sun and weather — that's the basis of the 5-Year No-Fade Guarantee. Reflective and metallic films are similar outdoors; frosted and interior films longer indoors. Pressure washing at close range and harsh solvents are what shorten the life.
How do I install decals?
Clean with alcohol, tape one edge as a hinge, peel the backing, squeegee from the center out, pull the transfer tape back at a sharp angle. About 5 minutes per decal; instructions ship with every order, and if you mess it up the Goof-Proof guarantee replaces it free once within 30 days.
Can you match my existing lettering?
Usually, yes. Send a straight-on photo of the current door with something for scale (a tape measure or a dollar bill) and we match font, height and layout on the proof. If the font is very unusual we'll show you the closest match before cutting.
Can I upload my logo?
Yes — after checkout the thank-you page has a logo upload, or reply to your order email with the file. Vector (AI, EPS, SVG, PDF) cuts cleanest; a sharp PNG/JPG works for simple one-color logos; photos and gradients can't be cut as vinyl. We show it on the proof before anything is cut.
How fast do you ship?
We email a free proof usually the same business day. After you approve it, standard orders cut and ship in 1–2 business days from Las Vegas, NV; RUSH ships the next business day after approval. Free U.S. shipping on every order.
Can I reorder the exact same decals later?
Yes. Every order confirmation carries a reorder link that rebuilds the order — same size, color, font and text — in one click, and this browser keeps your saved trucks under My trucks & reorders. Fleets with 5+ trucks get artwork and a spec sheet kept on file for one-email reorders.
This page is informational guidance from a decal maker, not legal advice. Federal rules: 49 CFR Part 390 (markings §390.21), Part 393 (conspicuity §393.11), Part 396 (inspections). Verify current requirements with FMCSA and your state agency; our state rules page lists the source and verification date for every state.
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