Replaced the right fan, but new fan is still noisy / makes new noise

Hello,

My early 2013 Macbook Pro will be turning 5 in March, and has had intermittent problems with the fans since I bought it. In its first year, the fans would be super loud and rev up violently, suddenly - that problem was resolved under AppleCare.

Since then, the fans have always seemed unusually loud, but I always just sort of dealt with it.

Earlier this year, the right fan started to rev up to an almost deafening degree (like a blender), randomly. This happened more and more frequently until I bit the bullet, bought the necessary parts and replaced the fan myself. Everything seemed to go smoothly and as planned.

So now I have a new right fan, and the new fan is making strange noises - a buzzing sound, which gets much worse when I physically tilt the machine.

The left fan works perfectly, quiet as always. I've reset the SMC, but that hasn't made a difference. Here's a video to showcase the problem:

The sound isn't as loud as it seems in the video, but it gives a good idea of what I'm hearing.

Does anyone have any ideas for solving this?

I don't want to replace the left fan, since it works perfectly and I'd rather not mess with that. The right fan is loud at low/all speeds, and temperature doesn't seem to be an issue. I've read things about fan "alignment," but can't find any specifics about that or how to address it.

Thanks and please help if you can!