Diagnosis
That’s the evaporator fan motor. It’s located behind the back panel in the freezer section. The bearings can wear out or ice can build up on the fan blade, causing a loud, persistent hum.
How to Fix It
Unplug the fridge. Remove all items from the freezer, then take out the shelves and the back panel (usually held by a few screws). You’ll see the fan. Check if the blade spins freely by hand. If it’s stiff or scraping, the motor needs replacing (part number WR60X10152). If it spins freely but there’s ice buildup, let everything defrost completely, dry it, and reassemble.
If That Didn't Work
If the fan looks and spins fine, the sound might be coming from the condenser fan at the very bottom rear, behind the kickplate. That fan cools the compressor. Pull the kickplate off and check for debris (dust bunnies, packaging foam) touching that fan blade.
Heads Up
When you remove the freezer back panel, be gentle with the wiring harness connectors. They have plastic clips, not metal pins, and can break if you yank on the wires.