Just seen this, no fitting instructions that I can see but it must be a better solution than a new hub. Rodders involvement will also give some comfort as to their effectiveness.
Polybush Rear Suspension Bush Kit, MX5 Mk4 & RF (mx5parts.co.uk)
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I wondered if this is something that’s easy to install or does it need to be a professional install? Looks good but pricey.
Thanks Mad Malc. I must say that the stories going around about hub failure on the ND have been very worrying. This looks like both a solution and an upgrade.
It’s the 2 spherical bearings which wear, not sure that replacing them with a poly bush is going to do the job.
Yes I did see that, but again I cannot see that replacing a spherical bearing with a poly bush is going to last.
What’s this rear hub issue?
It’s the two upper and lower bearings that fail. They are selling the set of four of them separately for under £180. That’s what is needed to do both sides. Don’t need to buy the full kit.
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This is good to know for the future…
Rob
I would think if Roddisons were involved then he would make sure it would be okay, as Mad_Malc mentioned.
There must be a reason Mazda use different types of joint in the hub, presumably to accommodate movement of the hub that a plain bush type bearing cannot, and maybe not influence the movement of the hub in an unwanted direction that a plain bush could?
All supposition on my part, and I’m sure the people involved in the development of the bush kit know far more than me, but an explanation of why Mazda used the spherical type bearing and what if any compromises the plain replacement introduces would be interesting, as would the reason Mazda will not supply replacements, only a complete assembly - to me at least.
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You can ask that whenever poly bushes are discussed (why don’t manufacturers use them etc.) a lot of it comes down to NVH (Noise, Vibration, Harshness) and I wouldn’t be surprised if the ride is firmer with these new replacements.
With other popular cars, special tools have been marketed to press the peccant bushes in and our in situ.
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Having used them I am aware of the nvh that can be introduced when using poly bushes, and diff whine if on the rear.
I wish I had the measuring equipment and facilities to measure what the rear hub does through its travel and when different loads are applied.
I read that Mazda went to some lengths on the ND to get it right, and iirc better stability when loaded with accelerative forces that alters to improve turn in as side load is applied, ie when cornering.
Fascinating subject.
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Had the same issue on my 2015 ND - purchased the four spherical polybushes and had them fitted by a local garage and now all is working well - no more clunking from the rear hubs and a lot cheaper than Mazda main dealer who could only quote for replacing both rear hubs and bushes completely
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Thank you for this update, I am sure it will give a degree of comfort for those of us yet to have this issue.
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I have a MX5 ND, got these from MX5Parts & had a local garage fit them for me, Polybush has a good reputation & I know going down this route I don’t have to worry they might fail again after 6 years.
Using Mazda’s only option of a £650ea to replace them for the same fault again in possibly 6 years time if I’m lucky (2017 ND Sport Nav) Glad I found this on the forum.
Thanks Mad_Malc you are a star 
PS. I got all the instructions in the box, I was told the old ones are a nightmare to get out but I wanted them all changed not just the ones that failed.
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Just thought I’d add my view on these as there’s not much info out about them.
I was debating between the poly bushes and the replacement bearings.
As they came from a reputable company I went down the poly bush route.
I was concerned about any difference in NVH as it’s my daily car.
I had them fitted at Roddisons and have to say I’m impressed. The car is much improved NVH wise over the worn original bushes. The handling appears unaffected. When pushing on I’d say the bushes took out a little slop under hard cornering…. But this may just be that I’d got used to havi mg slightly worn bushes.
Overall very impressed. Let’s see how long they last
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I had the mot advisory on mine in January so I’m going that route soon, I’ve just got get around to booking it in at Roddisons although it’s a bit of a trek from darkest Essex but it needs to be done. Does he serve coffee and biscuits 
?
It’s very much a recovery place first and foremost but I’m sure if you ask him nicely! I went into Sheffield for the day to entertain myself and he had it down in no time. Very friendly guy and obviously knows his way around these cars
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