02 Trd rear dif question

Hello everyone. I have an 02 Tacoma Trd x cab v6. I was changing my rear dif fluid today and noticed what looks like a small vent line of some sort coming out of the rear locker actuator section. Can anyone tell me what this is and what it's for?

Thanks

 

it's your diff breather which allows the air & fluid in the diff to expand/contract and not create undue pressure/vacuum within the diff.
if you plan on offroading & doing water crossings it is advised to raise this breather line above the possible submerged water line you may encounter.
search differential breather extension for more info

 

That is the locker actuator breather. Differential housing breather and locker breather are two different things.
The locker breather goes up to the frame with the locker wiring harness. On the end is a funky little rubber tip that can get hard or fall off.
This breather is often neglected, many folks don't know it's there.