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: Power Steering
Power steering is only operable when the engine is running. If the engine
is off or if the power steering system is inoperable, you can still steer, but
it requires more physical effort. If the steering feels stiffer than usual
during normal driving or the steering vibrates, consult an A ...
Mazda 6 Service Manual: Woofer removal/installation
4SD
1. Disconnect the negative battery cable.
2. Remove the rear package trim.
3. Remove in the order indicated in the table.
4. Install in the reverse order of removal.
5HB
1. Disconnect the negative battery cable.
2. Remove in the order indicated in the table.
3. Install in the rev ...