front differential leaking from vent tube

[mikebooms]

i have a 1998 tahoe 4wd that has had this problem a few times. what it does is it leaks front differential gear oil out of the top vent tube on the top left of the engine bay near the radiator. i leaks quite a bit. this has happened 2 or 3 times before, but it would stop once i refilled the diff. as of late it has not stopped after filling it twice.

[ChevyTech007]

Make sure the plastic vent at the end of the hose is vertical and in the retaining clip on the fan shroud.