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: Trunk Lid
WARNING
Never allow a person to ride in the trunk: Allowing a person to ride
in the trunk is dangerous. The person in the trunk could be seriously injured or
killed during sudden braking or a collision.
Do not drive with the trunk lid open: Exhaust gas in the cabin of a vehicle
is dangerous. ...
Mazda 6 Service Manual: Scheduled Maintenance (Mexico)
Follow Schedule 1 if the vehicle is operated mainly where none of the following
conditions apply.
Repeated short-distance driving
Driving in dusty conditions
Driving with extended use of brakes
Driving in areas where salt or other corrosive materials are used
Driving on rough or muddy ...