I once used a 600 lb rated torque battery impact . Of course the gland nut came right off, prepped the new one screwing it in by hand than marked about 45 degrees on the nut figuring that would be about right torque wise. I blipped the gland nut with the impact in a millisecond the nut broke off inside the crankshaft. At first I thought well shyt, that's the end of that crankshaft. Then I stuck my finger in the threaded part and turned it by hand until it was out of the crankshaft...….. Dodged a bullet.