Everybody I ask around here uses grease in their bush hog gear boxes along with 90 weight lube.
The reason for the lube is for the bearings - they won't get lubed by the grease.
The reason for the grease is sooner or later you will have a leak, and the whole thing won't burn up if you have some grease until you can get the leak fixed.
Soooooooo, my question is this: are there types/brands of lube and grease that are more compatible?? Nobody has said they had a failure from doing this, but I wonder if there are compatibility issues with the gear lubes and the greases? Or are they just creating a 500 weight lube??
Thanks, Von

You are making a thick oil or a thin grease.

Amsoil has a 00 grade grease that works good

I would stay with the manufacturer's recommendation. I have a Taylor Way finish mower, and a King Kutter bush hog, they both recommend 90W gear oil. I am running AMSOIL 85W 140 in the King Kutter though. I had to replace an input shaft seal and I refilled it with what I had on the shelf.

Fred, thanks, I didn't even think about the 00 Amsoil.
In fact, it seems like I saw some non-synthetic 0 or 00 at the coop one time and didn't even think about using it.
Great idea. I just don't know how heavy you can go and still get to the bearings?? All my cutting will be over 60 degrees air temp, and much of it in the 90's. The whole problem is there is no warning if you lose a gasket or have a crack in the box. It can run out with no warning. I've had both happen, but fortunately, they weren't catastrophic. I saw them while taking a break.
Doubleclutch, I always run 85-140 in gear boxes and differentials down here in MS for anything working hard. I left the 90 weight in the 1/2 ton p/u though.
When I was in the Border Patrol in CA, the mechanic that rebuilt the Bronco and Tahoe rear ends used 140W and said it made all the difference. Said they didn't have them come back in with 140, and I've used it ever since in severe service. Don't want to waste the gas in the 1/2T though.
Von

Engine assembly lube is usually 0 grease designed to be mixed with oil.

Great idea, Tempest. Thanks
Von