I spent entirely way too much time trying to get one of these style extruders on my Ender 3. Maybe I picked a knock off without realizing it, maybe mine was just defective, I’m not entirely sure.
But it was ultimately the cause for my printer underextruding on certain layers. If you need a new extruder, go for something better than these cheap $20 ones and get an actually decent one.
But on the bright side, my printer is finally fixed! It feels nice to be able to get back into the hobby again.
a lot of the amazon cheapos don’t have proper bearings on the gear, so you slowly wear out the the drive bolt. if you see gray powder forming… you have a problem. Some 3-in-1 (though I recommend the PTFE 3-in-1) will slow it down, but it’s still going to wear.