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: To Operate the System
The High Beam Control System (HBC) operates to switch the headlights automatically
between high and low beams after the ignition is switched ON and the headlight switch
is in the AUTO and high beam position.
The High Beam Control System (HBC) determines that it is dark based on the brightness
...
Mazda 6 Service Manual: Outside Mirrors
WARNING
Be sure to look over your shoulder before changing lanes: Changing
lanes without taking into account the actual distance of the vehicle in the convex
mirror is dangerous. You could have a serious accident. What you see in the convex
mirror is closer than it appears.
Mirror type
Flat ...