Drill keeps stalling and making weird noise - help!

Hey folks, my trusty cordless drill (DeWalt 20V, about 3 years old) has started stalling when I put any pressure on it. It also makes a grinding/whining noise at low speeds. Battery seems to charge fine (green light on charger). Any ideas? I'm in the middle of a deck project and really don't want to buy a new one.

First off, welcome to the forum! That grinding noise + stalling screams gearbox issue. Could be stripped gears or a bad bearing. Have you ever opened it up to check? Also, does it happen with all batteries or just one? If it's only one battery, could be the battery's cells going bad under load. But the noise points more to mechanical. Let us know!

I had a similar issue with my old Makita. Turned out to be the motor brushes. They were worn down and causing arcing, which made a whining noise and reduced power. Not sure if your DeWalt has replaceable brushes, but worth checking. Also, try running it without load - does it still stall? If it only stalls under load, could be the clutch slipping. Set the clutch to drill mode and see if that helps.

Before you tear it apart, try a different battery if you have one. I thought my drill was toast but it was just a crappy aftermarket battery that couldn't deliver enough amps. The grinding noise might be separate though. Could be the chuck? Sometimes the chuck gets loose and makes noise. Tighten it down good. If all else fails, a new brushless drill is like $99 at HD. Just sayin'.

Good point about the clutch, Gary. Also, Dan, does the noise change when you switch between speeds (if it's a 2-speed)? If it only happens in one gear, that narrows it down. And yeah, check the brushes if you can. If they're shot, you might see sparks inside the housing. Let us know what you find!