My DeWalt failed because the brushes wore out and I didn’t have a spare set on hand. If you’ve changed brushes, you know that they are held against the commutator by a spring. I suspect when the brushes wear too much there isn’t enough for the spring to push on. If I’m right, you could stick something between the spring and the brush to give it something to press against and get a little more life out of the brush. Has anyone tried this? Would it work? I might give it a try tonight after work and report back.