Couple Miata fluid questions.

[gbwrx]

What oil weight are you guys running. I was told 0w30 is what the prior owner used. He didn't have any particar brand but I was thinking about Amsoil.

Also I changed the thermostat and drained the coolant. What coolant have you Miata guys been using?

Thanks!!!

[lcoleman]

I think I ran Mobil1 10w40 or maybe even 15w50 synth in mine. 5W30 is recommended, I think, but a lot of people go thicker. It seems to make those hydraulic lifters chatter less. Amsoil is too $$$ for a turbo car, but I have used it before and really liked it.

On a car as basic as a Miata, I think antifreeze is just antifreeze (prestone ftw, haha). The water does the cooling anyway. Throw in some Water Wetter or the like if it needs a little extra. Be more concerned about your radiator--watch out for cracking on the plastic end tanks.

[Going in Hot]

Well there's all kinds of opinions over on miata.net (your new favorite forum) I just keep it pretty basic. I get valvoline full synthetic 5w30 because it's cheap. I run redline in the tranny and diff and change it once a year.

+ 1 on the antifreeze and radiator. When the radiator turns greenish it's about to crack.

[MARKP]

Your co-driver thinks that you should use Amsoil.

I don't have any 0w30 in stock but I can get it. I need to put another order in anyway.

[gbwrx]

That is why I said Amsoil.

I was more less interested in what weight everyone was using.

Luckily the radiator isn't very old on this car. The workshop manual I got with the car says to use an ethylene-glycol based coolant. The coolant that I have here from the Subaru is just that.

[Brian]

I've been using 0W-40 M1 mostly because that's what my other cars take so it's usually around. Last time I did a full flush, I put the blue BMW stuff in because I had a couple of gallons around the house.

[flier129]

I've always ran 5w30M1 on my n/a motors and my dad has too. Ran 15w50 with the turbo

Coolant is coolant, I ran distilled water and water wetter when it was 45+ degrees outside. But don't look at your radiator the wrong way, it'll crack right near the cap!

I use redline 75w90 MT for the transmission and jump between M1 and redline 75w90 (whichever is available) for the diff.