I have a similar leak on the passenger side. And it is a mess just as well. It appears to be the inner Axle/ CV seal but the way is drips down the side housing then off the pan it almost appear like the side housing is leaking. If this is the case can the seal or gasket inside that case be replaced while replacing the axle seal ? While it's in the car ? It leaks at a rate of a pint or two a month. Too cold here to replace it now but I want to be prepared for a nice warm day . Damn it was 30 below yesterday !