USDOT / MC / CA / GVW Four-Line

Not all of them. California's Motor Carrier Permit program covers motortrucks with two or more axles and a GVWR over 10,000 pounds and any vehicle used to haul property for compensation, but carriers operating only in interstate commerce are not subject to it (CHP FAQ). Whether your truck needs a permit and a CA number depends on its weight, its use and where it runs, so confirm with the CHP or DMV.

The CHP's FAQ lists the order: a USDOT number from FMCSA first, then a CA number from the California Highway Patrol, then a Motor Carrier Permit from the DMV. The DMV's permit page has the current steps, and our CA number guide explains the rest. Order your decal after the number arrives, so the digits are final.

Use a figure that matches your vehicle, such as the manufacturer's GVWR, which the federal rules define as the value the manufacturer specifies as the maximum loaded weight of a single motor vehicle. Do not round it up or down. If your truck is registered in California with a declared weight, use the figure the DMV has on file, and ask the DMV if you are unsure which one applies.

KYU is a weight-distance tax license issued by the Kentucky Transportation Cabinet to carriers traveling Kentucky roads with a combined license weight greater than 59,999 pounds. A TXDOT number is the old nickname for the TxDMV intrastate operating authority certificate, which is separate from a USDOT number. Check with the state agency before you letter either one on a door.

Letter size follows decal width, so four lines on a 12 inch decal are smaller than on an 18 or 24 inch one. The preview shows the stack on a door as you change width, so pick the width that stays clear at a distance. The federal rule asks for lettering readable in daylight from 50 feet and sets no height in inches. Our door decal size guide has more.