A changed exhaust system needs document (1). A free exhaust or anything that makes the silencer less effective is forbidden.
Inspection neededYes
Certified part neededNo
What you need to know
Only document (1) is accepted.
Document (1): report from an approved technical service on the compliance of the modifications with the legal framework (individual approval).
Noise limit for a new car or van: 82 dB(A).
Vehicles first registered before 1 March 1999 may not exceed 82 dB(A) up to 3,500 kg.
The exhaust must be sufficiently quiet, efficient and sealed, must not stick out beyond the vehicle outline and, on a petrol engine, must be completely outside the cabin.
Vehicles that meet the EU type-approval rules are deemed compliant (Arrêté grand-ducal of 23 November 1955, art.
25 and 25bis).
A combination of modifications that influence each other (for example wheels and suspension, spacers and suspension, power and wheels) always needs document (1).
The check must happen before the vehicle goes back on the road, or at the latest before the next technical inspection and never more than 2 months after the modification.
If the change is not entered in the 'remarques' field of the registration certificate, the inspection records a major defect.
If the documents are incomplete, the vehicle must go to an approved technical service for a compliance report.