Whirlpool vented dryer – drum struggling to turn and lots of noise

We have a Whirlpool vented tumble dryer (“American Collection”, model 3RLEQ8000KQ2). I’m not sure how old it is, as we inherited it from the previous owners of our home when we moved in 2.5 years ago, but it looks like a fairly old-fashioned “American style” dryer. It had been working great until last week (vastly more effective that the dryer portion of our previous combined washer/dryer).

However as of last week it rarely manages to start. When trying to start a drying cycle, the motor clearly tries to turn the drum, but makes a loud “grating” sound as it does so, and the drum usually only turns a little. After a few seconds it then seems to give up.

I figured out how to open the front panel of the dryer, and can see that the belt is not slipping – it just struggles to turn the drum. If I turn it by hand it seems somewhat stiffer than I might have expected too. Can anyone suggest what’s likely to be wrong with it? I took a video of it attempting to turn, whilst the bottom of the front panel was open, in the hope that might hold some clues: https://photos.app.goo.gl/o4AQ9Q5cjfPYisz27. Note that the “clicks” at the start and end of the video are me turning the electricity to the dryer on/off (ie that’s not an issue).

The main reasons I’m keen to repair it rather than replace it are:

– It was so effective when it was working
– I’m a bit wary of how much work would be involved in replacing it given the fact there is a hole in the side wall of the property for the vent; it’s hard-wired into the mains with a 32A supply; and the door frame in our utility room is cut around the dryer.

But if you think replacing it with something more modern is the way to go, I’m happy to listen to advice! Perhaps I just need to accept I’ll have to get some professionals in to fit a new dryer.