How to Install Decals on a Truck Door: Step by Step

This guide shows how to install decals on truck door panels: clean the surface, mark the spot with masking tape, press the decal down with a squeegee, and peel the top layer away slowly. Every Work Decals order includes a printed instruction sheet and a link to our install video, so treat this page as a companion to those. If your sheet and this page ever differ, follow the sheet.

Before you start

Watch the video on our installation page once before you touch the decal. Then get the door ready:

• Wash the door and let it dry completely. The surface must be clean, dry and free of wax or polish.
• Work in the shade, in mild temperatures, if you can.
• Measure and mark the spot with masking tape. Check that it is level and that the lettering will be easy to read from the side of the truck.
• Keep a squeegee, a clean cloth and a sharp blade or pin close by.

If the door still has an old decal, take it off first and clear any glue. Our guide on how to remove truck decals covers that.

Choose and mark the position

Pick a flat stretch with no seams, handle, ribs or sharp curves. Our truck door decal size guide shows how to measure it, and the guide on where to put a USDOT number on a truck goes into placement.

The federal marking rule, 49 CFR 390.21, asks for the marking on both sides of the vehicle, so you will install two decals. Measure the second door from the same landmarks as the first, such as the lower door edge and the window line, so both sides match. Our USDOT number display rules page has the summary.

Lay masking tape around the planned rectangle, step back a few feet and look at it. Moving tape is easy. Moving a decal is not.

Position the decal and make a hinge

A common method is the tape hinge. With the decal still on its backing, line it up inside your tape marks, then run a strip of masking tape across its top edge so it holds firmly to the door. The decal now swings up like a page, and it cannot slide out of line while you work.

Squeegee it on

How you proceed depends on how your decal is supplied, and your instruction sheet is the final word. For a decal on a backing sheet, usually with a clear transfer layer over the front:

1. Swing the decal up on the hinge.
2. Peel the backing away from the decal slowly, then cut the loose backing off.
3. Lower the decal onto the door without letting it touch yet.
4. Starting in the middle, press it down with the squeegee and work outward in overlapping strokes toward each edge.

Working from the middle out pushes air toward the edges instead of trapping it.

Peel the top layer and finish

If there is a clear transfer layer, pull it back slowly on itself at a low angle, close to the surface, instead of lifting it straight away from the door. If part of the lettering starts to lift with it, lay it back down, squeegee that spot again and continue.

Then:

• Press the edges once more with the squeegee or a clean cloth.
• For a trapped bubble, make a tiny pinhole at its edge and push the air out toward the hole.
• Remove the masking tape.
• Step back and check that the decal is straight and the lettering reads clearly.

Common mistakes

• Skipping the wash, or leaving wax or polish on the panel.
• Working in direct sun or on a hot panel when the sheet recommends shade and mild temperatures.
• Eyeballing the position instead of marking it with tape.
• Pressing down from one edge, which traps air.
• Pulling the top layer off fast or straight up.
• Letting the decal cross a seam, handle or rib, where it may not lie flat.
• Touching the adhesive with dirty fingers.

Care afterward

Wash the truck gently. Avoid abrasive cleaners and scrubbing, which our refunds and returns page lists as outside the guarantee. Keep a pressure washer's spray from hitting a decal edge head-on, since a strong jet can lift a corner. If your instruction sheet gives a waiting period before the first wash, follow it.

If something looks wrong

If a decal arrives damaged, or peels or comes off later, our 3-year guarantee covers a free replacement. Send your order number and a photo through the contact form. The decals themselves come from the Custom USDOT Logo and USDOT Decal Sticker pages.