Review on 🔧 Enhanced Automotive YG429 Motorcraft Vacuum Control Valve by Tim Lea

Not installed yet but whenever in 4LO at a certain RPM the hubs just made a popping noise followed by a grinding noise but the wheels wouldn't move. I would have to go back to 2WD and then back to 4LO if I wanted them COULD work again, but only for a few seconds. I have found that this check valve fails frequently and I checked it and it actually did. Check this by sucking up the vacuum with your mouth and closing the other hole with your finger. When you release your finger, it should still be on the tongue.