Help! My Milwaukee M18 Impact Driver making weird grinding noise and battery won't charge fully

Hey guys, having a weird issue with my Milwaukee M18 Fuel impact driver. It's about 2 years old, been solid until now. When I pull the trigger, it makes this grinding/rattling noise like something's loose inside. Also, the battery (5.0Ah) won't charge past 2 bars on the charger, even after leaving it overnight. Tried cleaning the contacts on both tool and battery, no change. Any ideas before I take it to a service center? Thanks!

OP, sounds like two separate issues. The grinding noise is likely worn planetary gears or a damaged anvil - common on impacts that see heavy use. For the battery: Milwaukee batteries have protection circuits that can fail. Try a different battery if you have one - if it works fine, your battery's BMS is probably shot. If you're out of warranty, parts are available online but it's tricky work. Personally, I'd send it in for service - cheaper than buying new.

Dude, I had the EXACT same thing happen with my DeWalt last year! That grinding noise turned out to be the hammer mechanism spring broke. As for the battery - check if the charger is getting hot. Sometimes the chargers fail and don't deliver full voltage. Also, try the battery in another tool if you have one. Milwaukee's customer service is pretty good though - might be worth a call before you crack it open yourself.

The noise description suggests either gear wear or debris in the gearbox. Have you dropped it recently? For precise diagnosis: 1) Remove the battery and rotate the anvil by hand - feel for roughness or catching. 2) Check battery voltage with a multimeter - a 5.0Ah should read ~18V when fully charged. If it's below 16V, the cells are unbalanced. Milwaukee uses Samsung cells which are generally reliable, but the BMS could be faulty. Document everything before contacting service - they'll ask for these details.