Hi , I’m a new member and trying to increase my MX5 knowledge. A horror to you purists but I have just purchased a MK3.5 2.0L with an automatic gear box… If I have read the internet literature correctly I believe the manual version has a limited slip diff but the automatic does not. I get the impression that the limited slip diff is the better of the two. Is it not necessary on the automatic because it is assumed (correctly) that people like me just want a comfy cruiser and are like driving Miss Daisy. Any information gratefully received
Welcome. Personally the first thing I did when I bought mine used was to ask Mazda what was the specs of my car.
You can email/call them and provide the registration (possibly the chassis number) and they will tell you all that there is to know.
https://www.mazda.co.uk/contact/
Thanks for the advice. I will chase this up.
Yep, no LSD on the auto. Do you pine for it? The Powershift (IMO) is a wonderful car. Do no be ashamed.
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Good luck with your Powershit, brill cars for comfort and I love the gearbox.
I tried to buy a Powershift and looked at a few of them over several months, just couldn’t find a low mileage good one; they seem as rare as hen’s teeth.
I bought a 2l manual in the end.
Enjoy your car, I’m envious.
Roy
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Hi,
I have had a 2L automatic MX5 2010 for over 3 years now and I love it. Does everything I want and does it well. It changes gear faster than me, never fluffs a gear change and won’t let me select 2nd when I meant 4th, that sort of thing, which I guess also gives the engine a more stress-free life. And I get to keep both hands on the wheel when pushing hard, which I like, and it’s just one less pedal to worry about. And if I want to emulate the old days, then I can stick it in manual mode, play with the paddles (or stick even) and pretend to be a teenager again (even though double de-clutching is off the menu!)
As to the lack of an LSD, I’ve driven a friend’s manual MX5 and I couldn’t tell the difference from that point of view. Now it may be that in certain low-grip or “on the limit of grip” situations an LSD can help get more traction, but for everyday driving I’m sure it makes no difference. I’ll get a wheel spin up when exiting a junction in the rain, but that’s no bother and maybe an LSD may not even kick in for that, or would it? Can manual MX5 drivers tell when the LSD kicks in when driving normally (whatever normal is for an MX5 driver)? Or is it just a sales gimmick?
Cheers,
Ian
I wouldn’t miss LSD for general road driving. I like car tours i.e. long journies for several days at a time but would prefer to have a Powershift than my manual 5 speed box, too late now though, I have made a few comfort mods to my car and love it, a tad envious of the Powershift thats all a lovely gearbox.
Roy
The differential allow the rear wheels to rotate at different rotational speeds during turning whilst we can still apply the power from the engine to the wheels to move the vehicle. If we didn’t have a differential both wheels would rotate the same rotational velocity which is fine in straight line but not great during turning (unless you want to drift)
In automotive definition terms, slip is the relative motion between a tire and the road surface it is moving on. and is effectively the ratio of the rotational velocity versus the forward velocity of the vehicle. So if Slip is 0 the tyre has lost traction, if its 1 its the ideal scenario and all the rotational velocity of the wheel, is converted to vehicle forward velocity. (Note that slip is usually around 0.8 max at least in my field of work)
However to allow the differential to function as above, if slip is reduced on a wheel and it starts rotating over a threshold compared to the opposite wheel, the LSD basically mechanically partially locks the differential (the wheel that has lost traction).
As for usage, basically its a helpful mechanical aid if you want to go faster on track however it will also help put the power down in situations you may not realise it works for your benefit… IMHO Nice to have if you are passionate about your driving.
Nice write up ckleanth.
Although I don’t recon I need LSD my Miyako does have it anyway, one reason I am not fussed about not having LSD is maintenance really, i.e. installing new plates would be a pain but I’ll worry about that if I ever need to.
As a matter of interest used for fast road driving approx how long will the MX5 slipper plates last?
My perfect choice would be to have a Quaife ATB that way it would increase long term reliability and do the same job as an LSD but without the plates; a tad costly if an MX5 slipper is working as it should already but if I was racing I would be looking at the Quaife ATB very seriously (assuming they are available for MX5 diffs).
For those interested here is a worthy link:
Roy
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Thats an interesting question and to be honest i don’t really know the answer to that. When I bought my car I checked that everything worked but I had no idea it had an LSD when i bought it and tbh I didn’t really realize it had one a couple of weeks after that 
During maintenance all i did (well the garage) was to change all fluids and check the LSD worked. Personally i wouldn’t worry that much about it, even if its not working properly they aren’t that expensive units to buy new or i presume get them serviced. To check if it works you need to jack the rear and spin one of the wheels lets say forward, if the other wheel also rotates forward the LSD works. I think for some LSD you can hear a clicking noise if you so a sharp turn at low speeds - not sure if the one in the mx5’s do that though.
Ah, I see the misunderstanding - I drive on the road, not in a field! 
I can see an LSD being very useful off tarmac…
(Sorry)
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