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: Automatic transaxle fluid (atf) inspection
Automatic Transaxle Fluid (ATF) Condition Inspection One way of determining whether the transaxle should be disassembled is by noting: If the ATF is muddy or varnished. If the ATF smells strange or unusual. ATF Condition Automatic Transaxle Fluid (ATF) Level Inspection Caution Th ...