Genuine Mazda Main Differential Pinion Lock Washer • 0223-27-012

Genuine Mazda 0223-27-012 Main Differential Pinion Lock Washer

Replacement Genuine Mazda main differential pinion lock washer for Mazda MX-5 Mk1 1.8, Mk2, Mk2.5, Mk3, Mk3.5, Mk3.75 and Mk4 models listed in the compatibility table.

The washer is fitted beneath the main differential pinion retaining nut. It forms part of the pinion fastening arrangement after the bearings, spacer and nut have been correctly installed and the specified bearing preload has been established.

The component is located at the differential input flange and pinion-shaft assembly. There is typically one main pinion lock washer fitted per differential. This listing is for one Genuine Mazda washer.

The washer should be inspected whenever the pinion retaining nut is removed. A washer that is distorted, cracked, heavily marked or corroded should not be reused. Incorrect assembly can allow the retaining arrangement to loosen or affect the established pinion-bearing preload.

• Part type: Main differential pinion lock washer / flange washer
• Primary use: Fits beneath the differential pinion retaining nut
• Location: Rear differential input flange and pinion-shaft assembly
• Quantity per vehicle: 1
• Quantity supplied: 1 lock washer
• Brand: Genuine Mazda
• Part No.: 0223-27-012
• Also referenced as: 022327012
• Fitment note: Suitable for MX-5 Mk1 1.8 and subsequent MX-5 generations
• Exclusion: Not suitable for Mazda MX-5 Mk1 1.6 models

Fitment advice: This washer is used with the compatible self-locking differential pinion nut. It should not be selected solely because it resembles a generic washer. Confirm the original differential type and pinion-retaining arrangement before installation, particularly where a replacement or modified differential has previously been fitted.

Other items to consider: When disturbing the pinion retaining assembly, consider purchasing the associated self-locking pinion nut, pinion oil seal, pinion bearings, bearing races and selective pinion spacer. Fresh manufacturer-specified differential oil and suitable casing sealant may also be required depending on the work being carried out.

Useful tools / consumables: Flange-holding tool, suitable socket, calibrated torque wrench, inch-pound rotational torque wrench, dial indicator, bearing pullers, workshop press, seal installer, bearing marking compound, assembly lubricant and manufacturer-specified differential oil.

Difficulty guide: DIY Difficulty: Advanced. Correct installation requires control of the pinion flange, accurate measurement of pinion-bearing preload and observance of the Mazda differential assembly procedure. Simply tightening the pinion nut without measuring preload can damage the bearings and final-drive components.

Why Genuine Mazda? Genuine Mazda differential hardware is designed to match the original pinion shaft, retaining nut, flange and bearing arrangement. Correct dimensions, material specification and contact surfaces help maintain the intended fastening arrangement and compatibility with the original differential components.

What’s in the box: One Genuine Mazda main differential pinion lock washer, part number 0223-27-012.

Installation notes: Follow the applicable Mazda workshop procedure when removing or installing the pinion flange and retaining nut. Fit the washer in the original position and orientation, use the correct compatible pinion nut and measure rotational bearing preload throughout tightening. Verify differential backlash and gear-tooth contact where the differential has been dismantled. Refill the assembly with the specified differential oil before operation.