2017 Expedition MAX 4x4. Recently, the truck has started to vibrate, but at the front end, during turning at low speed. Forward or Reverse. It feels very similar to the common rear LSD shutter that happens when you need to change fluid and LSD additive. It makes me think it's the front diff. I changed the fluid, which was very black and your shimmery, but no flakes. I plan to run this fluid for a month and go do some figure 8's in a parking lot to work it through, then change it again. What scares me is it almost seems like something may have happened that the drive axle is no longer firmly secured to ensure proper alignment between the bevel to the pinion. Like the cap cracked. From what I can tell, though, is the front diff cover can't be removed without taking out the steering rack. Anyone tried before? The vibration doesn't occur when at a complete stop and going knock to knock on the steering, so it doesn't appear to be rack related. No steering wheel wobble occurring either, so don't think it has anything to do with steering linkage or ball joints. Everything looks good underneath for those, too. Does anyone else have some theories as to what it may be?