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: Wheel hub, hub spindle removal/installation
Caution
Performing the following procedures without first removing the ABS
wheel-speed sensor may possibly cause an open circuit in the harness if it
is pulled by mistake. Before performing the following procedures, remove the
ABS wheel-speed sensor (body side) and fix it to an appropri ...
Mazda 6 Service Manual: Automatic transaxle fluid (atf) inspection
Automatic Transaxle Fluid (ATF) Condition Inspection
One way of determining whether the transaxle should be disassembled is by
noting:
If the ATF is muddy or varnished.
If the ATF smells strange or unusual.
ATF Condition
Automatic Transaxle Fluid (ATF) Level Inspection
Caution
Th ...