Coolant and yes I have searched and read

[Smallblock454]

I'll get it from BASF. See post #16 from Deserion.

It's G30 (OAT) for the 986. Why? Because it's an alloy engine. And because it has a very long change interval (very good long term stability) compared to other fluids.

In general it seems you can also use G40 (Si-OAT). But you have to flush the system completely.

Don't mix silicat free coolant fluid like G30 with silicat containing coolant fluid like G40.

I don't know how the parts in the 986 cooling system react on the silicat. Don't know if Si-OAT is 100% compatible with the 986 coolant system on a long term.

In general silicat reacts with alloy and generates a protective layer. But this layer doesn't last very long. So they developed the OAT coolant fluid. The long term alloy corrosion protection is much better.

This is why i would recommend to use BASF G30 for a 986 car.

The bottle jakeru shows is the newer G40 stuff.

Regards, Markus