When replacing any component of an exhaust emissions system, whether a catalytic converter, DPF, front pipe, or complete exhaust assembly, it is essential that all associated fitting kits, gaskets, rubber hangers, clamps, and mounting bushes are replaced at the same time.

Failing to do so is often a false economy. If the exhaust system itself has reached the end of its service life, it is highly likely that the supporting components have also deteriorated through age, heat cycles, corrosion, and continual vibration.

A new exhaust system is typically heavier than the unit being removed. Corrosion and material degradation can significantly reduce the weight and structural integrity of the original exhaust over time. As a result, worn mountings and hangers may no longer be capable of correctly supporting the replacement system.

Insufficient support places additional stress throughout the exhaust assembly, increasing load on welds, joints, brackets, flanges, catalytic converters, and diesel particulate filters (DPFs). This can lead to premature component failure, excessive vibration, and exhaust leaks.

Exhaust leaks can have serious consequences for modern emissions control systems:

• Air leaks upstream of a catalytic converter can affect exhaust gas readings and contribute to incorrect fuelling, potentially damaging the catalyst coating and reducing conversion efficiency.
• Air leaks around a DPF can affect pressure readings and regeneration performance, increasing the risk of premature blockage.
• Air leaks near oxygen (lambda) sensors can result in inaccurate sensor readings and may trigger fault codes such as P0420  Catalyst System Efficiency Below Threshold (Bank 1).
• Exhaust leaks can also negatively affect vehicle emissions performance and increase the likelihood of an MOT failure.

For these reasons, EEC strongly recommends that all new exhaust systems and emissions control products are installed using new fitting kits, gaskets, clamps, hangers, and mounting components. Correct installation not only ensures optimum performance and longevity but also helps protect the vehicle’s emissions system from unnecessary stress and premature failure.

Replacing the exhaust without replacing the associated fitting components may save money initially, but it can significantly increase the risk of future failures, additional labour costs, and warranty related issues.

A professional installation should always include the replacement of all relevant fittings and mountings. After all, a new emissions system is only as reliable as the components supporting it.