Every six months I change my refrigerator filter. I purchased a new filter (UKF8001) and installed it just like I've done many times before. This time, when I first used the water dispenser, I got a horrible sound (kind of like a jack hammer/vibration) followed by very little water flow. I disconnected the new filter and reinstalled the old filter, thinking maybe I got a bad filter. No improvement. I removed the filter and put the bypass cap on and everything returned to normal. Since everything went back to normal following bypass cap installation, I figured I must have a bad water filter head. I ordered the part, swapped it out and everything is back to normal.