My 87 Quad developed a gearbox oil leak in the last few weeks. After determining the oil level was a little low (ruled out overfilling from the fluid change 2 months ago Redline 75w90NS), I went in to check the shifter boot and it was torn. I carefully changed the boot and meticulously cleaned up the residue around the gearbox and surrounding area. I went about 36 hrs and two 15 mile drives before another puddle appeared on the floor below the shifter area of the gearbox. I went back in and the boot is fine, and the clamp is tight. The area around the vents are coated in oil. The vent housing bolts are tight. The vent tops look clean, but is it possible the gearbox is becoming pressurized enough that when it finally vents, its squirting up fluid with the air? The only other thing I can think of is the rubber boot that goes over the shifter boot is resting right on the vents causing a pressure build up. Has anybody experienced this or anything like it and have any suggestions. Do the vents covers come off to be cleaned, or can I give them a quick blast of low pressure air to release any goop on the insides of them. I'm just thinking they might look ok from the outside and are dirty on the inside causing a pressure build up. PS. output shaft seal looks good/dry. The leak definetely appears to be coming from the vent area of the shifter tower. Thanks.