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: Speedometer, Odometer, Trip Meter and Trip Meter Selector (Without Multiinformation
Display)
The speedometer indicates the speed of the vehicle.
The display mode can be changed from odometer to trip meter A to trip meter B
and then back to odometer by pressing the selector while one of them is displayed.
The selected mode will be displayed.
Odometer
The odometer records the total d ...
Mazda 6 Service Manual: Thermostat
THERMOSTAT REMOVAL/INSTALLATION
1. Remove the plug hole plate.
2. Disconnect the negative battery cable.
3. Drain the engine coolant. (See COOLING SYSTEM SERVICE WARNINGS.)
4. Remove the drive belt. (See DRIVE BELT REPLACEMENT.)
5. Remove the washer tank.
6. Remove the P/S oil pump.
Note
...