This why I use the Aircat 1150 I have with V style couplers and plugs. But there still some bolts that requires a 3/4" pull bar with a 5 ft cheater along 3/4" drive 15/16 socket and serious blocker for the blade. So far the only blade I can't get loosen has been those 5/8" bolts on the Gravely HD52, Even PB blaster don't help. I going to try my own Acetone/trans mix next time. I do know they are self tightening beyond the Gravely torque spec. And I know the Aircat should have plenty of torque as I have twisted 1/2" extensions in two with it, not mentioning how 1/2 lug studs I have twisted off due crossed lug nuts.
Now did get some kinda penetrating lube that worked but he has refused to tell me what it was. Why I don't know as it sure would be helpful here in my shop too.I hate having a sore back for weeks at a time from using the pull bar setup.
With the MTD these are exposed to moisture, impacts, and other things during mowing that can damage the end threads of the spindle shafts. This is why I have die to cleanup the threads when possible and install new flange nuts. I don't take chances reusing damage nuts.
But there are case where the ACE/OX torch has to used too to get things apart because rust or over torqued items.