ive got a Makita XPH07 (DPH451)18v cordless drill. Its become intermittent and pretty much not working at all. Ive replaced the trigger thinking it was that, but the problem still persists making me think its the brushes, except its a brushless drill. Ive tried different batteries. I wantThe armature doesnt spin easily turning by hand
Bearings that have dried out could be your issue. I regularly find I can pull seals add a penetrating oil work the bearings until they free up clean them out and grease / oil depending on the bearing type and the motor works for another few years, since your armature is stiff I would be checking the bearings.