Does a brand new MX5 need rust-proofing in the UK?

I’m new to MX5’s, and I keep hearing about their susceptibility to rust. So I’m interested to know whether it would be a good idea to apply some underseal or similar immediately after taking delivery. Are the NDs any less prone to rust than earlier models? And are there any downsides to undersealing or things to avoid? Has anyone else taken the step of rust proofing their new ND after delivery?

If you’re planning to keep it long term or care about the longevity for future owners then yes, see link:

 

https://www.mx5oc.co.uk/forum/yaf_postsm601952_Mk4-Underseal-How-To.aspx 

Great link, thanks! After reading the comments I have to agree, it’s rather shocking that Mazda aren’t really prepping their cars for European climates…

We had our last MX for 17 years from new and if I had known then what I know now I would have had it undersealed as soon as we got it. Being naive I assumed “being new” then it would have been properly treated by Mazda before leaving the factory. At the time it was our intention to keep it but never thought it would be for 17 years! (We end up having the sills done after 7 years and they were still OK when we sold her last month. (Never used in the Winter). I have considered getting our new car done, but then I am not thinking of keeping it for anything like 17 years.

So I guess it depends on how long you expect to keep your car. (If 7+ years then indefinably), I am not sure getting it done will add any extra value to you car when you come to sell, but it may make it a bit more “desirable” come selling time. 

I’m nigh-on certain that I’ll replace my MX5 after the 3yr PCP period has elapsed, even if to just get in another new one. So any rust-proofing I do now won’t benefit me personally. But I’m sure many will agree with me when I say that manufacturers of anything, cars or otherwise, have an environmental responsibility to make stuff that lasts! Although I appreciate that recycling of cars has improved dramatically in recent years. And, I’m aware of my own hypocrisy in citing environmental responsibility whilst buying a new car… :confused:

The Mazda anti-perforation guarantee specifically excludes any corrosion caused by salt.  So in UK it is worthless from the start.

 

The first thing I did to my new Mazda3 back in 2016 was to have it wax injected and fully under-sealed by a Dinitrol specialist (not the Mazda dealer), with special attention to the inevitable rust traps behind all the many, many plastic covers. 

As a cash purchase for a low annual mileage shopping trolley and family holiday carry-all, and probably the last car we will buy before they take our licenses away because of senility, I thought overall it was a very good investment - goes very well, economical, comfortable, reliable, and now in theory rust free…

In your case knowing that you’re unlikely to retain the car after 3 years, I’d say … “why spend the money.”

Corrosion probably won’t be a problem until maybe year 10+.

You won’t get any extra return when you come to trade in at the end of the PCP.

It will probably require a top up in 3 years anyway, which is unlikely to happen.

There’s absolutely no benefit to you.

 

The third or fourth owner might thank you for extending it’s life by a few years though.

I suppose you could sleep soundly in 2029 knowing that the car might still be on the road.

 

Laughing

 

Welcome to the family by the way.

I had my ND SE-L  Nav treated with Dinitrol shortly after purchase and will be having the same done to the 30AE shortly.  For the cost involved against the price of the car not to do it would be in the words of the old saying “spoiling the ship for a ha’p’orth of tar”.

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Thanks! I’ll introduce myself properly in the new forum member area soon. Nice forum! 

 

I’d tend to agree! How much do you think I should expect to pay if I do decide to do ‘pay it forwards’ to a future owner?

 

To give you some idea of potential cost, I’ve just been quoted £450.00 for the 30AE.

Ouch!

(Shaking fist at Mazda for not doing this at the factory!)

(Now feeling silly after realising that factory rust-prevention would just add £450 to the list price…)

 

“Ouch!”  To put that into perspective, you’re considering spending that or more on having four suspension springs replaced!

 

My ND2 will be getting the treatment soon, say a day’s labour and about £130 in materials.

 

That’s a fair point. But on consideration, I see suspension upgrades as non-essential extras that the consumer should pay for if chosen. Whereas rust protection is a basic fundamental that the manufacturer should assure before every car leaves the factory. I commend you for choosing to invest in the long-term integrity of your 30AE! It’s just a shame that you have to because Mazda didn’t do it on the production line.

As above if you are keeping it long term get it done my RF was 2years old when I sold it and it was going rusty undeside…and it was only a weekend toy

   

I doubt you’ll find any make/model that comes with adequate underbody protection, it’s just that you’ve become aware of the lack of it on Mazda’s because of the fraternity of the MX5 OC and forum.  

What’s the consensus on this…

I rode motorbikes for years, and I swore by ACF50. The usual approach; a final autumn deep-clean followed by a good layer of ACF50. Then I didn’t really wash the bike until it got a spring deep-clean that revealed a shiny rust-free ride. Lovely!

If a pinch a go on a friends car-lift, I could just coat the whole underside of my MX5 with ACF50. Sure, it’ll need topping up every year and it’s not as good as a proper treatment. But would it be worth it from a cost+effort/benefit perspective? Has anyone else done this?

Some manufacturers are clearly better than others, but I think you’re right. Bigger and more active owner community = more attention to detail.

In any case, none of this rust talk is detracting from my eager anticipation of getting behind the wheel of my first MX5. 

 

  

Good!  You WILL have fun!