[deliriousga]

In other forums there are people who have talked about tests showing the Chevron or Texaco DexCool works well and does not hurt the engine.

If you only need a little, just add water. Don't add a different coolant into the existing stuff. Some people have done this and ended up with jelly. If you change coolants, empty the system and do a flush before you fill with the new stuff.

Porsche approved coolants include "Porsche" brand coolant. That's it.