Raise the car.
Check the reliability of the installation of the fastening brackets.
Use a carrying lamp to check the absence of chafing and burnouts on the muffler.
Replace badly deformed muffler pipes.
By stretching and bending the rubber suspensions, check that they are not cracked, otherwise replace them.
Vehicles with a catalytic converter: check the tightness and electrical connections of the lambda probe.
Every 60,000 km: Tighten the bolts securing the front pipe flange to the exhaust manifold to a tightening torque of 45 Nm.