Hey guys,

I'm now in the process of doing the brakes on my truck (I'll update the build thread soon). However, I'm caught up in the rear. There is a random hose that I have no idea where it goes or what it's for. Here are some pictures:

It's on the rear left side, and it is the hose towards the bottom... The end is just sitting on the ground right now.



And here's a picture of the fitting that the hose attaches to:



Any ideas? Help is greatly appreciated. Thanks!

 

It's a vent hose for the rear axle. It doesn't connect to anything on the other end. It should be attached up on the frame to keep water out - if you look you may find a metal clip on the top of your frame rail that used to hold it.

 

Awesome, thank you! Should I plug it for bleeding the brakes, or will it be okay?

 

No need to plug it. Just vents the rear end.

 

2x... it needs to be open. Plugging it will result in the hot, expanded gases within the rear axle to blow out the seals/gaskets, resulting in a leak.

 

This is how it should look, the line clipped to the frame to keep it up, out of the way.
Also, before you put the hose back on the fitting. HIO is correct, the vent hose needs to be open not plugged. While the nipple that the hose connects to is large, the actual hole in the nipple is relatively small and plug up easily.
Make sure the little hole in the nipple is clear and not plugged up. If it is plugged, run a drill bit through it to clean it out. If you don't it could lead to unexplained axle seal leaks.