A little more info. When I cleaned my red T3, I took apart the coil and forgot about the two extra wicks that are placed there just above the coiled wick. I then tried using it and it leaked a bit and gurgled a lot. I then remembered about the extra wicks and was lucky enough to find them on the drain strainer I had placed in my sink. Dried them off and put them back on and the leaks and gurgling stopped. The T3's do tend to gurgle a bit when they are almost empty, like down to the wicks. Adding more juice stops the gurgling.
Maybe those extra wicks are missing in the coils that leak? I have also heard of someone who got a defective tube. He bought just a tube and it worked fine with his old coils from the defective tube.
Could it be the tube? Maybe I should just try to order another one as opposed to assuming the coil was the issue.... but I wonder how a bad tube would cause it to leak out the bottom onto the battery?