The Volvo Group has detected that an emissions control component used in certain markets is degrading more quickly than expected.

Predominantly affecting Volvo Trucks in North America, the failing part could cause the affected engines to exceed emissions limits for oxides of nitrogen (NOx).

The degradation is due to a materials issue that occurs over time.

A full analysis of the issue is not completed and it is not possible for Volvo Group to assess the financial impact at this stage; however, it believes the cost could be material.

The degradation of the component does not pose a product safety issue, nor does it negatively affect vehicle or engine performance in areas other than emissions control. The degradation is a result of a materials issue that occurs over time. All engines and vehicles equipped with the component meet emissions limits at delivery.

The largest volume of potentially affected engines has been sold in North America and Europe.

In a statement, the company said: “A full analysis of the issue and plans with regulatory authorities are not completed and the company is therefore not yet able to estimate the volume of engines or vehicles that may need to be addressed. Consequently it is not possible to assess the financial impact at this stage; however the cost to redeem the issue could be material.”