Front Box (16") Code - AHT G Pipe Connection

[Yozza]

Ay up,
Had the front box out and noticed that there was a loose pipe in in the vicinity and sure enough, there is a male pipe connection on top of the box. (Just for reference, the box doesn't have a front locker on it). Any idea what this pipe connection is about folks?
Cheerz

[Aidan]

There's a breather pipe attatched to a banjo bolt, breather vents above fuel tank, so that air inside can expand and contract as required without loading the seals, there's one on the gearbox too and the bellhousing on petrol vans.

[Yozza]

Cheerz Aid, I knew you'd be along with your words of wisdom.