Coolant choices
 

Coming from BMW where the blue coolant was called for and used because of the finicky cooling systems. I have a new-to-me 1998 Boxster. What is the preferred coolant for these cars? Something special or the generic aluminum radiator safe Prestone?

I just went through this and there are many options back in the US. I live in Japan and the domestic stuff for Japanese cars was not advised due to some additives. I could find OEM and VW coolant at $25 per liter that would work but the dealers won't sell it outright. I ended up finding 2 other options locally; the first was GM DexCool at about $35 per gallon, and the next lucky find was Prestone DexCool at $15 (I think the basic Prestone is ok too?). Anyway, I went with what I could find and it's working great. Good luck!

Zerex GL5 extended life will work fine if you done want to spring for the dealer stuff.

That being said, I used the P car stuff in my car for two reasons:
1. No guessing or opinion required.
2. Total added cost was abut $30 more than aftermarket....not much of a difference for 60K miles.

Well, it’s slightly more complicated than one or the other. It really depends on what it has in there now. If you don’t know, it would be best to flush it and start from scratch. The Porsche stuff isn’t all that expensive when you consider a gallon is actually two as it is undiluted and will be a 50/50 mix. Lots of opinions on the overall subject, but as mentioned above, using the Porsche factory stuff, you know exactly what is in there and no guessing.

When I did the water pump/thermostat on the '06 last year, I went with OE coolant. Comparing to Pentosin G12/G12+ in local stores, it ended up being cheaper. Purchased through FCP Euro where they give warranties on it, even. ;)

What color do you have now - Green or Pink?
P-car lifetime coolant was green up to some where very early 2000's, then they switched color to Pink.

I had green so at WP/Thermo replacement I flushed and went P-car Pink

I have stuck with OEM coolant, you can move to something else, but make sure you thoroughly flush the entire coolant system with distilled water before you do. If what is in there isn't pink or green, indicating OEM, flush it before you change it to anything else. Mixing different kinds of coolant can cause problems.