Before You Start / Safety
- Work on a level surface with secure axle stands.
- Wear eye protection when cleaning old grease/debris.
- If axle hardware is removed, follow model-year FSM torque/staking procedure exactly.
Warning: “The sooner you are able to spot this issue, the less money you will end up spending on repair or replacement work.” https://mechanicbase.com/transmission/symptoms-of-a-bad-cv-joint-replacement-cost/
Required Tools
- Jack and axle stands
- Wheel tools
- Light, mirror, and gloves for boot inspection
- Degreaser/clean rags
- If replacing: axle-nut tools, boot clamp tools, and suitable puller/pry tools
Required Parts / Fluids
- Replacement CV boot kit (correct inner/outer and side) or complete axle assembly
- CV joint grease supplied with the boot kit (use the grease pack intended for that joint)
- New boot clamps from the kit (do not reuse stretched old bands)
- New axle nut/locking hardware as required by your parts/manual
Practical parts-identification checklist
Before teardown, record:
- left vs right side,
- inner vs outer boot,
- ABS ring/tooth layout,
- axle-nut hex size on your car,
- spline count/diameter if your supplier requires it.
Model-specific notes (NB1 vs NB2)
- NB rear driveline service can involve axle part-number/fitment differences in aftermarket catalogs.
- Confirm replacement hardware dimensions and ABS/non-ABS compatibility before disassembly.
Manual-reference quote: “The Manuals are in PDF format. You can use Adobe Reader to read or print them.” https://www.mellens.net/mazda/
Community quote: “there is a potential for no source of NB axles new or re-manufactured” https://forum.miata.net/vb/showthread.php?t=659375
Step-by-Step Procedure
1) Inspect boots before noise diagnosis gets worse
With the wheel turned for access, inspect both inner and outer boots for:
- cracks in fold valleys,
- tears near clamp lands,
- missing/loose clamps,
- grease sling on damper, control arm, and wheel-well liner.
2) Decide service path: boot-only vs axle/joint
- Boot-only candidate: tear found early, joint still quiet/smooth, minimal contamination.
- Full axle/joint replacement candidate: clicking while turning, heavy vibration, or obvious contamination/wear.
High-risk quote: “The most common cause of CV joint issues is a lack of grease… often caused by a broken CV joint boot.” https://mechanicbase.com/transmission/symptoms-of-a-bad-cv-joint-replacement-cost/
3) If replacing boot only, keep contamination extremely low
Disassemble, clean thoroughly, inspect race/balls/cage for scoring, repack with kit grease, and install new boot/clamps.
Clamp orientation tip: clock clamp ears so they do not foul nearby suspension components through full steering and suspension travel.
4) If replacing axle assembly, confirm fitment details first
Before final install, verify axle spline/nut/hardware compatibility with your NB configuration.
Community confirmation quote: “The axles are all the same…except for Mazdaspeed…the nut size does not make a difference..29 or 32” https://forum.miata.net/vb/showthread.php?t=659375
5) Reassemble and secure axle-nut lock method correctly
After final torque per FSM, apply the required locking/staking method.
High-risk quote: “Staking means that after the nut is torqued, you bend one of the tabs up against one of the flats of the nut so that it is locked into place and cannot loosen.” https://forum.miata.net/vb/showthread.php?t=310577
Torque Specs / Capacities
- Boot clamps and grease quantity are kit-specific.
- Axle nut torque/staking must follow exact NB year/VIN factory specification.
- This guide intentionally avoids publishing one universal torque value due year/variant differences and source extraction limits.
Verification / Post-service checks
- No grease leakage/sling after short drive
- No click on full-lock turns
- No new vibration under load
- Re-check clamps and axle-nut lock condition after initial heat cycle
Uncertainty / Open Questions
- Publicly extractable data in this environment did not provide one definitive universal NB axle-nut torque/staking table across all years/variants.
- Aftermarket axle catalog consistency for NB can vary; verify by VIN, ABS spec, and spline/nut details before install.
Images
No reusable images were added in this run.
Image Credits
- No images used.
Sources
- Mellens.net — Mazda Miata Factory Service Manuals. Retrieved 2026-02-27. https://www.mellens.net/mazda/
- MechanicBase — 5 Signs Of A Bad Or Failing CV Joint. Retrieved 2026-02-27. https://mechanicbase.com/transmission/symptoms-of-a-bad-cv-joint-replacement-cost/
- ScegliAuto — Mazda Mx 5 - CV joint (tutorial index). Retrieved 2026-02-27. https://www.scegliauto.com/en/video/mazda/mx-5/giunto-omocinetico/tutorial/
- Miata.net Forum — NB Axle Shafts. Retrieved 2026-02-27. https://forum.miata.net/vb/showthread.php?t=659375
- Miata.net Forum — Question about replaceing rear cv axle assembly. Retrieved 2026-02-27. https://forum.miata.net/vb/showthread.php?t=310577