Mazda 6 Service Manual: No.22 vibration concerns (engine)

No.21 engine noise

No.23 a/c does not work sufficiently

Other materials:

Mazda 6 Service Manual: Driving on Uneven Road
Your vehicle's suspension and underbody can be damaged if driven on rough/uneven roads or over speed bumps at excessive speeds. Use care and reduce speed when traveling on rough/uneven roads or over speed bumps. Use care not to damage the vehicle's underbody, bumpers or muffler(s) when driving ...

Mazda 6 Service Manual: Noise filter inspection
Brake Light Noise Filter 1. Inspect for resistance and continuity between the noise filter terminals using an ohmmeter. If not as specified, replace the noise filter. Rear Window Defroster Noise Filter Inspect for resistance and continuity between the noise filter terminals using an ...