Mazda RX-8 Workshop Manual page 1533

12. Measure the ring gear preload between the backlash.
Ring gear preload
0.49—2.45 N·m {5.0—24.9 kgf·cm, 4.4—21.6 in·lbf}
NOTE:
When moving the gear case component in the axial direction, replace the adjustment shims. If the adjustment shim on the right side
is replaced with one that is 0.05 mm {0.0020 in} thicker, replace the one on the left with one that is 0.05 mm {0.0020 in}
thinner.
Bearing Cap Assembly Note
1. Align the bearing cap alignment marks and assemble the bearing cap with the arrow facing outward.
Tightening torque
72.6—106.9 N·m {7.41—10.91 kgf·m, 53.5—78.84 ft·lbf}
2. Perform the drive pinion and ring gear tooth contact inspection.
Drive Pinion, Ring Gear Tooth Contact Inspection
1. Apply tooth marking compound evenly to both surfaces of the ring gear.
2. Rotate the ring gear back and forth for several times.
3. Inspect the tooth contact pattern in 4 locations around the ring gear, and verify that the tooth contact points exhibit the pattern shown
in the figure.
If the tooth contact points are normal, wipe off the marking compound.
If the tooth contact points are not normal, adjust the pinion height, then adjust the backlash.