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: Camera and Sensors
Forward Sensing Camera (FSC)
The Forward Sensing Camera (FSC) detects lane indications and recognizes headlights,
taillights and city lights during nighttime driving. In addition, it also detects
the vehicle ahead, pedestrians, or obstructions. The following systems also use
the Forward Sensi ...
Mazda 6 Service Manual: STEP 3: Contact Better Business Bureau (BBB)
Mazda North American Operations realizes that mutual agreement on some issues
may not be possible. As a final step to ensure that your concerns are being fairly
considered, Mazda North American Operations has agreed to participate in a dispute
settlement program administered by the Better Busi ...