I closed my barn doors tonight and I heard liquid sloshing around in the right rear door. Is this normal? I never noticed it before last night.

 

No! Come on there Phil, you've been too involved in watching the Phillies haven't you?

Someone posted somewhere about noticing condensation inside one of his Clubman's rear tail lights... There must be something that's not fitting right. Got to get that fixed ASAP!

 

I'm thinkin' sloshing water (oh, wait you said liquid. hmmm...) in the door is not normal, Phil.

 

...or
There may be a bad silicone seal on the window.

I remember seeing something about this on the Club door window once.