REAR AXLE VENT

I seem to be losing gear fluid in the area where the brake lines go into the ftting on top of the axle. Looks like there is some sort of vent cap here that goes thru this fitting? I am sure it gear fluid, not brake fluid. what causes this, how do I fix?

The rear may be over filled with gear oil.

I don't think that is it, I filled it to the bottom of the side hole. Never had this happen before on other cars. Do you know is this a vent, or is it a screw just to hold the fitting in place?

Its a vent.Lets pressure release from the raer.Where is the oil coming from?The vent bolts do get plugged at times.Rocky

It's wet in that area, around the fitting. So I thought if it was just a scrwew holding the fitting in, i could take it out & put some sealant around the threads. But if it's a vent, it had me worried that there was pressure getting built up in there, and forcing the fluid out. Will it hurt anything to plug it if it were a vent?

Don't plug it or you'll have the axle seals leaking. Take the vent out, make sure it is open and reinstall it. You can put sealant on the threads if you like just make sure the vent is working.

as said its a vent and oil shouldn't be leaking out of it unless its way overfilled . if its not gear oil its brake fluid

Ok, the cap on it has a spring loaded rubber seal. The seal is wet, so it seams as though the vent is open, not plugged. I'll take out the fitting, seal the threads, maybe find a little heavier spring to put behind the rubber seal. Hopefully that will do it.
Thanks everbody....any other input is greatly appreciatd!!