F150 MYSTERY GRINDING NOISES $8 FIX

Diagnosing terrible grinding noises coming from the F150 front end. The 4x4 front hubs were locking and unlocking while driving down the road. It sounded like a brake issue or a loose heat shield. This is a common issue on 2004+ F150s with integrated wheel ends (IWE). There's a TSB from Ford for this here: https://static.nhtsa.gov/odi/tsbs/2020/MC-10171859-0001.pdf Check valve here: https://www.amazon.com/gp/product/B000C5HZ24/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1