Front End Leak - JD 3320 - only when the 4x4 is used.

[VPFarm]

My JD 3320 4x4, ~550hrs, developed a slight leak last spring after I used switched it to 4-wheel drive and used it for about 3-4 hours in a swampy area I was clearing out. It's only the front left tire and nothing 'major', but it looks ugly as sin and really bugs me. The strange thing about this leak is that it ONLY happens when I use the four-wheel function and only after it really heats up (~1 hr or more constant use).

The problem started about ~<500 hrs and since I bought this from a guy at 350 hrs (original owner, very light use brush hogging grasses.... I know the man) I went ahead and did the 600 hour service and front end fluid once I saw the problem. The fluids all looked great/normal and the filters were pretty clean.

Does anyone here have a easy fix for this or know what the root cause might be? I didn't think I did anything out of the ordinary that might cause this myself; I beat up my car more than my tractor.

[pedalstomper78]

I would start with a few of the easy things to look at and see why there's a leak. Go through and check to make sure that all bolts are secure. Also, jack up that wheel and make sure that there is no play in the bearings. Also go to the vent on the front axle and make sure that it is not clogged. You would be surprised at how many seals leak because pressure builds up and can't escape through a clogged vent.

[VPFarm]

Thanks pedalstomper. Never thought to look for a vent and jacking up the front will be a breeze......let's hope it's a vent hole.
That advice is much appreciated