Mazda MX-5 Miata Sport 2007 Manual page 509

2006-08 TRANSMISSION Automatic Transmission Overhaul - MX-5 Miata & RX-8
Fig. 246: Identifying O-Ring On B4 Brake Piston
5. Remove the O-ring from the sleeve.
Fig. 247: Identifying O-Ring On Sleeve
6. Remove the O-ring from the inner brake piston.
Fig. 248: Identifying O-Ring On Inner Brake Piston
B2, B4 BRAKE AND F3 ONE-WAY CLUTCH INSPECTION
1. Using vernier calipers, measure the free length of the piston return spring.
B2 brake return spring free length
2007 Mazda MX-5 Miata Sport