1. Measure the gap and height between the front or rear door and the body.
2. If not as specified, loosen the front or rear door hinge installation bolts or the door lock striker installation screws, and reposition the door.
Clearance
a: 2.5-4.5 mm {0.10-0.18 in} b: -0.8-1.2 mm {-0.03-0.05 in} c: -0.3-1.7 mm {-0.01-0.07 in} d: -1.0-1.0 mm {-0.04-0.04 in} e: -0.5-1.5 mm {-0.02-0.06 in}

3. Tighten the bolts or screws.
Rear door removal/installation
Front door glass removal/installationMazda 6 Service Manual: Radar Sensors (Rear) (Some models)
Your vehicle is equipped with radar sensors (rear). The following systems also
use the radar sensors (rear).
Blind Spot Monitoring system (BSM)
Rear Cross Traffic Alert (RCTA)
The radar sensors (rear) function by detecting the radio waves reflected off
a vehicle approaching from the rea ...
Mazda 6 Service Manual: Rear oil seal
REAR OIL SEAL REPLACEMENT
1. Remove the flywheel. (MTX) (See CLUTCH UNIT REMOVAL/INSTALLATION)
2. Remove the drive plate. (ATX) (See DRIVE PLATE REMOVAL/INSTALLATION)
3. Remove in the order indicated in the table.
4. Install in the reverse order of removal.
Rear Oil Seal Installation Note
...