Mazda 6 Service Manual: No.20 noise occurs at idle when vehicle is stopped in all positions/ranges

No.19 excessive shift shock on torque converter clutch (tcc)

No.21 noise occurs at idle when vehicle is stopped in d, s, l ranges, or in r position

Other materials:

Mazda 6 Service Manual: Underbody Maintenance
Road chemicals and salt used for ice and snow removal and solvents used for dust control may collect on the underbody. If not removed, they will speed up rusting and deterioration of such underbody parts as fuel lines, frame, floor pan, and exhaust system, even though these parts may be coated ...

Mazda 6 Service Manual: Heated Steering Wheel (Some models)
The grips on the left and right of the steering wheel can be warmed up. The ignition must be switched ON. Press the switch to turn on the heated steering wheel. The heated steering wheel operates for about 30 minutes and then turns off automatically. The indicator light illuminates when the h ...