My first pinion bearing went bad at around 35k and had more of an intermittent sound at around 15-35mph. Tech rode with me and immediately said pinion bearing. They replaced pinion bearing and was good for about 8k more when I started hearing that exact noise in your video. Just took it in and they replaced all the bearings (pinion, carrier, axle etc.) and so far sounds great. Also, feels like it rides almost like new again. Think the bad bearing/s were creating drag or I just have a placebo effect now that it's fixed.
What year is your car? Im guessing 2014 because you said "ride in another 2014 on the lot".
PM Deysha on the site, her username is fordservice and let her know your situation. She has been a great help to me and many others on the site.
Just re-watched the video and noticed a small click/clunk sound several times when the accel/decel changes. Don't know if thats something off camera or whatnot but kinda sounds like coming from rear. Possibly carrier bearings also?
Last edited by greytrotter; 07-24-2015 at 06:23 AM.
Reason: car year, knocking sound