1. Inspect the dust boot on the drive shaft for cracks, damage, leaking grease, and looseness in the boot band.

2. Inspect the drive shaft for bends, cracks, and wear in the joint or splines.
Joint shaft disassembly/assembly
Drive shaft removal/installationMazda 6 Service 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 ...
Mazda 6 Service Manual: Front drain hose installation
Caution
If the front drain hose is pinched or bent anywhere, the water in the hose
may not discharge and enter the inside of the vehicle. During and after
installation of the trims and the headliner, always make sure there is no
interference with the front drain hose. Fix any problem if found ...