ET 40 rims

ET 40 rims: balanced offset for many vehicle designs

ET 40 rims have an offset of 40 millimetres. This figure indicates how far the rim’s contact surface is offset from its imaginary centre line. The offset therefore has a direct influence on how far inwards or outwards a wheel is positioned within the wheel arch.

ET 40 is one of the values commonly found on numerous modern passenger cars. Depending on the rim width and vehicle design, this offset can enable a balanced position between sufficient clearance from chassis components and a harmonious wheel cover. However, the interplay of all dimensions is always the decisive factor. For example, an 8-inch-wide rim with an ET of 40 will occupy a different position to a significantly narrower or wider rim with the same ET value.

Why the offset must not be considered in isolation

When buying rims, an ET of 40 should always be considered alongside the other technical specifications. Of particular importance are the bolt circle, hub bore, rim diameter, rim width, load capacity and tyre size.

The design of the rim also plays a role. Two wheels with identical dimensions may offer different amounts of space for the brake caliper due to differently shaped spokes. Therefore, not every ET 40 rim is automatically compatible with every vehicle. The relevant type-approval documents and the Vehicle types and conditions listed therein are binding.

Alloy rims and Steel rims with ET 40

In the field of alloy rims, ET 40 is available in many sizes. Manufacturers such as Borbet, Ronal, CMS, Dezent, Autec and Alutec offer numerous wheels with comparable offsets. The range extends from understated standard replacement wheels to sporty Multi-spoke and double-spoke designs.

Steel rims are also available with an ET of 40. Brands and manufacturers such as ALCAR, MW and Accuride stock robust steel rims for various vehicle applications. They are frequently used for winter tyres or as a functional replacement solution.

Those who place particular importance on appearance will find aluminium wheels with finishes in silver, black, anthracite, bronze or a high-gloss finish. With Steel rims, on the other hand, the focus is more on durability, practicality and, in most cases, a lower purchase price.