I didn’t know the MTA was doing this, but apparently from the YouTube video description: As part of an ongoing project to reduce wheep slip on trains, a rail grinder is used to make grooves in the rail for better traction, and as a result this sound is made when trains go over the rail. […]
I believe this is the 91st Street abandoned station along the 1/2/3 line. I’ve always wanted to go here.
Amazing. This needs to be real. This station is unbearable at times.