Tranny Leak? Help needed with Part ID

Seems I'm leaking tranny fluid. The line below appears to be the source. It looks like it comes from the tranny but visibility is limited. Anybody know what this line is (the one with the red band)? It appears to terminate at the top , back, of the the engine block - slightly to the driver side. Odd...
Thanks for your help.

 

I think I've tracked it down to being be a tranny vent....

 

Possibly, here is where the vent is located on the Automatic transmission if your truck is the 4.0/6 cyl.
https://www.tacomaworld.com/threads...-the-front-diff-to-leak.761349/#post-27147395