Bush hog gearbox mount sideways?

[ning]

Good points on why this may not work if submerged. I stand corrected.

…but if the volume of oil and air expansion in the gear box is less than the volume of the extension tube, won’t that still limit the pressure that can build in the gear box that can blow out the seals? (i.e. limits the pressure to the “head” of the tube?) Worse case it pushes some oil out of the tube and not the seals?

Yes, it would work, especially if the vertical portion which is above the lube level had sufficient volume to handle the expansion, you may even avoid leaking lube during expansion. However, that tube would be a serious weak spot for that gearbox. I could see it working for a while but at some point something's going to hook onto that breather tube and break it off, and it could damage the threads of the gearbox where it's attached. I'd definitely look for an alternative for anything other than proof-of-concept.