Mazda MX-5 Miata Sport 2007 Manual page 791

Fig. 45: Measuring Probe Of Dial Gauge Attached To End Of One Of Ring Gear Teeth
Courtesy of MAZDA MOTORS CORP.
8. Secure the drive pinion and measure the backlash of the ring gear.
Backlash of drive pinion and ring gear
Standard: 0.09-0.11 mm {0.0035-0.0043 in}
Minimum value: 0.05 mm {0.0020 in} or more
Variance: 0.07 mm {0.0028 in} or less
NOTE:
2007 Mazda MX-5 Miata Sport
2007 DRIVELINE/AXLES Differential - MX-5 Miata
Measure the backlash at 4 locations around the ring gear. Make sure

all of the 4 locations are within specification, and the minimum value
for the 4 locations is 0.05 mm {0.0020 in} or more and the variance is
0.07 mm {0.0028 in} or less