How do you tell what type of plastic a bumper is?
Most bumper shells today are polypropylene (PP) or a PP-based thermoplastic olefin (TPO) blend, with ABS or PC/ABS used on some models. You can usually confirm the plastic type by checking a resin identification code on the bumper or by consulting the vehicle’s official documentation.
Car bumpers are more than a smooth shell: they include an outer cover and often a foam backing for energy absorption. Material identification matters for repair, painting, and recycling. The following guide walks you through practical steps to identify the bumper plastic with safe, non-destructive methods and official sources.
Where to look for identification codes
The easiest starting point is to search for a resin identification code on the bumper itself, typically molded into the inner surface or printed on a sticker near mounting points. If a code is present, note the triangle with a number (1-7) and any accompanying letters that hint at the resin family (for example PP, ABS, PC/ABS).
If you can't find a code on the bumper, check the vehicle’s service data, parts catalog, or the OEM’s online parts database using the VIN or bumper part number. In some cases, the information is listed in the owner’s manual or repair guides for your specific model year.
To locate the material quickly, try these steps:
- Inspect the inner surface of the bumper cover for a resin identification code (the triangular recycling symbol with a number). If present, record the number and any letters (for example "PP" or "PC/ABS").
- Look for a label or stamp on the bumper near the mounting brackets or inside the wheel well that states the material (for example "PP" or "ABS").
- Cross-check the bumper part number in the dealership’s parts catalog or the vehicle’s service manual to confirm the recommended material.
- If the code or documentation is not accessible, contact a dealer or a professional body shop with your vehicle make/model and year for material confirmation.
In most cases, resin codes plus official part data provide the most reliable identification, while visual inspection alone may not distinguish blends like PP vs TPO.
Common bumper plastics and how they behave
Understanding typical bumper materials helps with repairs, painting, and recycling. Here are the most common types you’ll encounter on modern vehicles.
- Polypropylene (PP): The dominant bumper shell material on many current cars. It’s lightweight, flexible, and can be molded into complex shapes. If the bumper shows a PP code or is described as PP-based in OEM data, expect a softer, weldable surface that needs a PP-specific adhesion promoter before painting.
- Thermoplastic Olefin (TPO): A PP-based blend with elastomeric components, common in newer bumpers for improved impact resistance. TPO often requires specialized primers or adhesion promoters designed for PP/TPO surfaces for best paint adhesion.
- Acrylonitrile butadiene styrene (ABS) and PC/ABS blends: Found on some models, especially earlier generations or specific makes. ABS tends to be stiffer and can be easier to identify by a dedicated ABS code or by the surface feel if the code is unavailable.
- Foam backing: The energy-absorbing core behind the shell behind the bumper cover is typically polyurethane foam in modern bumpers, sometimes with additional materials in high-performance applications. This is not the bumper cover material, but it affects repairs and recyclability.
Recognizing these materials helps you choose the right repair techniques, primers, and paint systems, and it informs proper recycling practices when replacing parts.
Additional considerations for paint, repair, and recycling
Materials influence surface preparation, primer selection, adhesive compatibility, and even disposal. For polypropylene and TPO, you’ll typically need a PP-specific adhesion promoter and epoxy or urethane primer, followed by the correct base coat and clear coat. ABS and PC/ABS often accept standard epoxy primers but may still benefit from adhesion promoters for reliability. If in doubt, consult a professional body shop or your vehicle manufacturer’s repaint guidelines.
When working with bumpers, avoid aggressive solvents that can melt or craze the plastic; always test a small area first and follow product manufacturer instructions for plastics repair.
Summary
Identifying bumper plastic usually starts with a resin identification code on the bumper shell and/or official OEM documentation. The outer bumper cover is most often polypropylene (PP) or a PP-based TPO blend, with ABS or PC/ABS found on some models, and polyurethane foam backing is common behind the cover. Use the code and OEM data for the most reliable identification, then follow material-appropriate preparation, priming, and painting guidelines or consult a professional for repairs or disposal.
