All About Rubber Grommets

Did you know that a typical car may use hundreds of rubber grommets? Rubber grommets are often taken for granted – so much so that we don’t really appreciate them until they either fail or go missing.

In automotive applications, grommets are essentially a type of seal, fashioned from rubber and other materials (i.e., nylon), and having a multitude of applications. In vehicles, grommets are used to protect lines, wire and cable from chafing or abrading on rough surfaces, to minimize vibration, and to act as seals in various under-the-hood and body applications.

When used to protect lines and cables, various types of rubber grommets are often used. 

  • Edge grommets, which are provided often as a continuous strip manufactured in various sizes and lengths, are used to protect lines and cable running along the edges of rough surfaces.

  • Rubber cable grommets protect cables and lines running through holes cut into metal or plastic panels and sheets. The shape of the cable grommet is molded in such a way as to keep the grommet firmly in place once it is inserted into the hole. 

  • Strain relief grommets are fashioned from rubber or plastic and are designed to grip and anchor the cable or line which passes through them, thus relieving some of the stresses associated with flexing, twisting or pulling. 

  • Sleeved grommets are made with a tapered flexible sleeve which allows an embedded cable to flex towards its free-end, thus preventing fracture of the cable insulation.

The material from which a grommet is made is an important factor to consider when selecting a grommet for a specific application. This is especially critical for automotive applications where grommets are often exposed to severe-service conditions as well as the effects of ageing through exposure to UV light. Choosing the right material will ensure that the grommet performs optimally in-use and resists premature deterioration and degradation.

CRGI has extensive experience in providing rubber grommets to leading automakers and their tier 1-3 suppliers. We specialize in supplying grommets of all types and sizes, manufactured from a wide variety of compounds and materials, and which meet ASTM D2000 line call-outs, as well as the material specifications of major automakers. Applications we have supported include washer tank pump grommets, fuel pump grommets, firewall grommets, A-pillar grommets, and trunk grommets, among others.

However, CRGI goes beyond just the mere provision of grommets – we always look for ways to add greater value to our customers by helping them to improve the efficiency and effectiveness of their operations. For example, in one program for a major automaker, CRGI greatly improved the efficiency of the customer’s lineside grommet installation process. This was accomplished by supplying a grommet made from a rubber compound containing a lubricating additive. This additive eliminated the need for lineside workers to immerse the grommet in soapy water to permit an easy installation, thereby increasing the efficiency of the overall assembly process.

CRGI can provide guidance and support to ensure that customers choose the optimal compound for a given grommet application. We also provide a full range of services to support the supply process, including: assisting customers with math data and 2D/3D CAD drawings; program management; EDI; bar coding; global logistics management; inventory warehouse management to support JIT delivery; and the provision of all levels of PPAP.

For more information on rubber grommets and other automotive rubber products and parts which CRGI can supply, please download our brochure or contact Paul Carey, Automotive Sales Manager, at