Rizmah

So my drill started making this weird noise, very different to the usual noise. I’ve opened it up, cleaned everything, took the rust off the yoke etc but I didn’t take apart the gearbox thus didn’t regrease it. I think you should be able to just view the video here and not download it: https://we.tl/t-aqnHhQS6w1 I thought it could be the armature bearings but I’m not sure. Help!