Also, another question. If I were to take it apart and find liquid while my car is under warranty... Will tesla do anything or are they refusing until catastrophic failure? Not sure if you know this question, but figured it's worth a shot. I got 6 more months left on my 2013.
Next time I get a chance, I'll try to make a video. We don't have a Model S in our shop at the moment, but maybe I can at least demonstrate how to remove the cover on my 70D for you (it wont have the Large Drive Unit or the same speed sensor, but the splash shield removal should be pretty much exactly same).
I don't know if Tesla will do a warranty repair or not if you find liquid, but it would definitely be worth at least getting in touch with the to see. Has your drive unit ever been replaced? And how many miles do you have? Especially on earlier cars, drive units had a problem with the bearings wearing out, and making noise, if your motor is noisy, they will definitely replace it under warranty.