Used cars surge prompts replacement parts warning

19 September 2025  

A surge in the UK’s used car market has underlined the need for high-quality replacement parts, according to aftermarket emissions control specialists BM Catalysts.

Data released by the Society of Motor Manufacturers and Traders showed there were more than two million used vehicle sales in the first quarter of this year — the highest quarterly figure since 2019.

And as more drivers turn to used vehicles, BM said this reinforced the importance of high-quality emissions control components in maintaining roadworthiness, performance and compliance.

With a 2.7% year-on-year increase, the market continues to be dominated by internal combustion engine vehicles, with petrol and diesel models accounting for over 90% of all used sales.

As technicians are aware, components such as catalytic converters, DPFs and front pipes play a vital role in ensuring vehicles meet emissions regulations and operate efficiently, BM said. However, the use of low-grade or poorly manufactured parts can result in increased emissions, poor fuel economy, and ultimately, MOT failures.

‘Growing concern’

Mark Blinston, BM’s commercial director, said: “Used cars are an increasingly attractive option for motorists, but maintaining their long-term health and compliance hinges on the quality of parts used during servicing and repair.

“Substandard or unapproved emissions components are a growing concern in the aftermarket. These parts can trigger warning lights, degrade faster, and even result in non-compliance with MOT standards.”

While the 2035 ban on new petrol and diesel vehicles edges closer, ICE-powered vehicles will remain a fixture on UK roads for many years to come — particularly in the used vehicle segment.

BM said it will support the transition by supplying premium emissions products that help lower vehicle emissions, extend component life, and support clean air targets.