Replacing shock absorbers: Do I replace all 4 or just the rear ones? And is it worth upgrading?

Technical Area Steering & Suspension
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  1. My model of MX-5 is: Mk3 2.0 Niseko with retractable hard top 2008
  2. I’m based near: Hertford
  3. I’m looking for technical help or recommendations on: Shock absorbers

I picked up my first MX-5 in April and I’ve loved every minute of driving it. Recently I’ve noticed there is a small pool of red liquid on the road underneath the NSR shock absorber. The bottom of the shock absorber is soggy too. Time for some new shocks I think. I can’t see any documentation saying they’ve ever been replaced, so they could well be the original shocks. If so, they’ve done well to last 15 years and 70k miles.
Do I just replace the rear shocks, and wait for the front ones to go too? Or do I bite the bullet and get all 4 replaced, and enjoy a bit more peace of mind as well as better handling?
Also, is there anything else worth replacing at the same time?
I’m assuming the car is fitted with standard shocks, so I’m thinking I’ll stick to standard but I’m open to suggestions/recommendations…
Thanks in advance
Steve

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My NC is 17 years old still on orignal shocks. O/S/R leaking so booked in to have all four replaced with coilovers in september. Just as well get it done all at the same time.

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At 15 years and 70k miles, personally I’d replace all 4.

4

Myself I’d go for all four and original spec.

However a lot of people will suggest after-market “upgrades”, maybe even with adjustments for ride and height (ie so many permutations it’s impossible to get the balance right without special equipment)

Fortunately I don’t need to cross that bridge yet, as my Niseko is not yet showing any sign of distress, but then it’s only done half the miles and still feels superb.

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Thanks for the quick responses. Much appreciated. I think I’m now sold on replacing all 4. None of the other three are leaking yet but it’s only a matter of time. I’ll speak to my mechanic next week (when he’s back from holiday) and get a price. Hopefully I’ll have enough money left in the kitty for a couple of new tyres. If it makes the car a little less twitchy when I stick my foot down on an uneven road, I’ll be a very happy man.
Update: I ended up just getting the rear shocks replaced, so I had money leftover for some new rear tyres too. Car drives better than ever now, and it’s quieter too. Happy days.