A squirrel chewed thru the squirrel cage, and no one has a direct-replacement plastic one, so I had to use this $16 metal one from NAPA or O'Reilly (I forget now).
The motor was very hard-to-turn, so I removed it, sprayed penetrating oil into the vent hose hole, and let it soak into the lower bushing overnight. Then I flipped it, added more oil, and let it soak into the front bushing. It freed up, so I chased that with engine oil, and the motor worked for another ~2 years. Eventually, I replaced it with a new Siemens motor.
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Blower Motor Siemens PM249;
Motorcraft MM527; Visteon 100066
Blower Motor Connector
Motorcraft WPT041Blower Wheel
Motorcraft MM1071, Siemens BW9308 (smaller metal)
Blower Motor Resistor
Motorcraft YH1698; Wells JA1176; Standard RU-318; BWD RU1013; Dorman 973-011 (973-412 with pigtail)
Blower Resistor Connector Dorman 973-307; Standard Motor Products RU318; ACDelco 15-80675