The washers are Mazda part number 9956-41-800, they come in packs of 5. They measure
18.25mm id
24mm od
1.43mm thick [new thickness, the washer is aluminium and is designed to crush when the correct torque is applied].
Torque should be:
22-30ft/lb for the engine sump
29-43 lb/ft for the gearbox drain, 18-29ft/lb for the filler
29-40ft/lb for the diff drain and filler/level plug
Spanner sizes needed
Engine sump 19mm
Gearbox drain 24mm, fill/level 14mm open ended spanner, or 16mm bi-hexagonal ring spanner
6 speed transmissions have a 24mm filler plug.
It is advisable to crack off the filler plug before draining the oil as the plugs can be tight. Doing so avoids the danger of having drained the oil only to find you are unable replace it.
You will need 24mm socket/spanner for the drain plug on the gear box
& the differential, the filler plug on the differential is a 23mm.
The filler plug on 5 speed transmissions is a square head plug which can
removed using a 14mm open ended spanner or a 16mm bi-hexaganal ring
spanner or socket. 6 speed transmissions have a 24mm filler plug.