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: Fuel Gauge (Without Multiinformation Display)
The fuel gauge shows approximately how much fuel is remaining in the tank when
the ignition is switched ON. We recommend keeping the tank over 1/4 full.
If the low fuel warning light illuminates or the fuel level is very low, refuel
as soon as possible.
Refer to Warning Lights.
NOTE
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Mazda 6 Service Manual: Rear bumper removal/installation
1. Disconnect the negative battery cable.
2. Remove the rear combination light.
3. Remove in the order indicated in the table.
4. Install in the reverse order of removal.
Rear Bumper Removal Note
Pull the rear bumper ends (wheel arch) outward to disengage with the bumper
slider.
Cautio ...