Questions About VPI Scout Motor Noise

I have a 5-year old VPI Scout with the standard 600 RPM motor. A few months ago, I started noticing “rumble” from this turntable during quiet passages and between tracks. I consulted VPI and they recommended lubricating the motor bushing with a drop or two of 3in1 oil. This solved the rumble problem, but lately, I’ve noticed that the motor makes a “swishing” sound that is audible when you’re close to the turntable. The noise persists with the belt disconnected, so it is coming from the motor itself. To other VPI owners, do you notice any noise emanating from your motor?

Again, I consulted with VPI. This time, they suggest lubricating the motor spindle with “Royal Purple Racing Oil,” which they claim will eliminate any noise from the motor. Has anyone tried this type of oil to lubricate their turntable motor? I hate the thought of buying a quart of this stuff only to use a drop or two. Plus, I’m not convinced that it will eliminate the noise. Thanks in advance for your comments.