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: Audio control switch removal/installation
Note
The audio control switch and the cruise control switch use a
common connector.
1. Disconnect the negative battery cable.
2. Remove the driver-side air bag module. (See DRIVER-SIDE AIR BAG MODULE
REMOVAL/INSTALLATION.)
3. Remove the steering wheel.
4. Remove in the order indicated ...
Mazda 6 Service Manual: Rocking the Vehicle
WARNING
Do not spin the wheels at more than 56 km/h (35 mph), and do not allow
anyone to stand behind a wheel when pushing the vehicle: When the vehicle
is stuck, spinning the wheels at high speed is dangerous. The spinning tire could
overheat and explode. This could cause serious injuries.
...