[JayG]

I'm not even sure I need to replace my cap. It is the latest ver, -04.

I know the cooling system is a closed system.
The level in my tank goes up and down a little over a few weeks. I see no drips or leaks and the trunk is bone dry. I check it when the engine is cold

I'll put in maybe 2-3 oz of distilled water and that changes the level from the min to midway between min and max.
What I did notice is a little condensation on the trunk lid above the cap. On my car there is a rubber gasket that "seals" the trunk lid to the oil/coolant fill thingy

The condensation is very minimal, no dripping, but definitely moist and you can see very very small drops of water, kind of like on a bathroom mirror after a shower

I'm thinking the cap "might" be going, dont't know