A cheap, quick, & reliable repair for most Ford window motors is to replace the degraded Delrin bushings in the motor's drive gear with common 1/4" nuts (thread pitch doesn't matter). Grease is only necessary on the central shaft & the outer plastic gear teeth - not in the pockets where the nuts go, though grease on the nuts may help them stay in place while the center gear is being installed.

For more info, see this:

Owner caption June 2009 · Photo 865 of 980