1. Verify that the joint shaft is not twisted or cracked.
2. Turn the joint shaft by hand and verify that the bearing rotates smoothly and freely.

Drive shaft
Joint shaft removal/installationMazda 6 Service Manual: Front combination light removal/installation
Caution
Incorrect servicing of the discharge headlights could result in
electrical shock. Before servicing the discharge headlights, always refer to
the Discharge headlight service warnings. (See DISCHARGE HEADLIGHT
SERVICE WARNINGS)
Note
When the ignition switch is turned to ON, ...
Mazda 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 ...