It should be EP90, that stinks too
If the gasket or seal is leaking you will see signs of oil running down the back plate where the half shaft goes into the axle casing. The half shaft is only held in place with one small screw and the pressure to seal the gasket is supplied when the wheel nuts are tightened up, so if it's been on stands with the wheels off for some time the joint could have started to leak, if this is the case then clean the oil off the back plate and put the wheels back on to see if that cures it. Other than that it could be the seal which, I believe, isn't a difficult job although not done it myself.
Also make sure the brake shoes haven't been contaminated with oil, they will need replacing if they have