What parts are needed for Kitchenaid Mixer? Do I need a new motor?

Appliance Parts
1

Please make sure to click on General above and select the correct appliance type first.

Brand: Kitchenaid professional 600
Model Number: KP26M1XPM5
Main Symptom: Noise
What happens & when: noise when on speed 4, a bit louder at higher speed level. The noise level now is much less than before I removed the old grease and put new grease on all gears and bearings.

Motor test: resistance between line wire and neutral wire shows OL with a Fluke meter but motor runs.

Do I need a new motor? Do I need a new control board? What parts should I change besides the worm follower gear?

Error Code (if any):
Parts or tests already tried: cleaned control board with compressed air, removed old grease and put new grease on all gears and bearings, measured resistance of motor between line wire and neutral wire (OL read with Fluke meter)
Photos / video link:

2

Is it the motor or the gears that get louder? If it is just the motor, then I would replace the motor. If it is gears, replace the worm gear and the planetary gears. It’s hard to tell also, I can’t hear what you are hearing. Some of that is normal. I just rebuilt my KA mixer. It is still loud, but it works ok.