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 under the following conditions:

This vehicle is equipped with low profile tires allowing class-leading performance and handling. As a result, the sidewall of the tires are very thin and the tires and wheels can be damaged if driven through potholes or on rough/uneven roads at excessive speeds. Use care and reduce speed when traveling on rough/uneven roads or through potholes.
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TowingMazda 6 Owners Manual: Saving Fuel and Protection of the Environment
How you operate your Mazda determines how far it will travel on a tank of fuel.
Use these suggestions to help save fuel and reduce CO2.
Avoid long warm-ups. Once the engine runs smoothly, begin driving.
Avoid fast starts.
Drive at lower speeds.
Anticipate when to apply the brakes (avoid ...
Mazda 6 Owners Manual: Manually Shifting Down
You can shift gears down by operating the selector lever or the steering shift
switches (some models).
M6 → M5 → M4 → M3 → M2→ M1
Using selector lever
To shift down to a lower gear, tap the selector lever forward (-) once.
Using steering shift switch (Some model ...