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: Manual Transaxle Shift Pattern
The shift pattern of the transaxle is conventional, as shown.
Depress the clutch pedal all the way down while shifting; then release it slowly.
Your vehicle is equipped with a device to prevent shifting to R (reverse) by mistake. Push the shift lever downward and shift to R.
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Mazda 6 Service Manual: Installing Child-Restraint Systems
Accident statistics reveal that a child is safer in the rear seat. The front
passenger's seat is clearly the worst choice for any child under 12, and with rear-facing
childrestraint systems it is clearly unsafe due to air bags.
NOTE
Even if your vehicle is equipped with front passenger occupan ...