Took the wife's car for a spin last week and the car could barely back up. I drove it for 10 or so miles and tried to back it into a parking spot but it just wouldn't go. No specific noises or anything, just wouldn't go.

Follow up a few days later and I'm able to back it out of the driveway but its definitely struggling to do so. No grinding noise but more of a humming sound. Kind of weird.

I have a few days off coming up next week and want to try to diagnose what the issue is. Any tips would be appreciated. Once that's done I can finally get those rear quarter windows working again! Thanks in advance.