So I have a 2005 RX8 and from what I understand if I had FL22 coolant then my rad cap should mention it?

I'm assuming that the rad cap is the one that you can see immediately by the overflow reservoir when you pop the hood?



Edit: Closest that I can determine I do NOT have FL22. From the TSB 01-033/07: FL22 coolant in factory installed in 2005 - 2008 RX-8 vehicles with VINs greater than JM1FE17**5*155009.

 

No, it takes FL22 regardless of what the cap says.

 

yep, if you car had FL-22 then it would have a sticker.

 

The caps differ, my new new reservoir and cap look like yours, my old one said FL22 on it. Both are factory caps.

 

hmm good point.

 

my 2005 rx8 came with regular coolant.

but 9k has a point, if it has been replaced then you will not see the sticker, the sticker can be ordered thru m-store.

 

https://www.rx8club.com/tech-garage-...licone-238638/

 

So... long story short there's no way to tell what coolant I have, since the sticker may or may not be there?

 

well it doesn't matter as FL-22 is compatible with the regular stuff.

it doesn't look like that coolant bottle has been replaced, and a 2005 wouldn't have been filled with FL-22 from the factory anyways

if you buy the FL-22 at a Mazda dealership, they should have the sticker, it comes with the coolant

 

Well no, it does matter.

If I have FL22 then I don't need to do anything - I'm good for another 5 years.

If I have regular coolant than I want to replace not only because it's time to do so, but because of the damage that regular coolant can do to the seals.

I take it there's no way to tell from the colour?

 

You actually believe the FL22 stuff will last that long?

good luck. feel sorry for ur car tho

 

Flush well....replace.....every 50K ...or 4 years at least...even the stupid FL22 stuff

 

I'm going to trust the engineers at Mazda and Ford. After all what would they have to gain by recommending a shorter replacement interval other than increased revenue from the customer, and less likelihood of problems that they would have to pay under warranty? If the TSB from Mazda says factory filled coolant is good for 10 years then I'll believe them.

Anyway... I found the TSB describing the coolant (01-033/07) and it says:

FL22 coolant factory installed in 2005 - 2008 RX-8 vehicles with VINs greater than JM1FE17**5*155009

Since I'm below that and my tank doesn't indicate FL22 anywhere I'm going to assume that I don't have it. Based on other threads I'm also going to assume that switching to FL22 is probably a good idea. I want to install an in-line heater anyway, so flush & fill works with that .

According to another thread the FL22 is the same as Ford's VC-10 which hopefully I can find for a good price. Are there any other good coolants that don't have 2-EHA?