I have an 09 f150 5.4, 76,000 miles, replaced everything with oem ford parts , cam phasers, and new variable seloniods, new timing ghain and tensioners, and installed a melling high volume oil pump, no fault codes idles and runs smooth, except when climbing a hill I still have the chattering noise, contacted fordtechmakuloco on youtube and he suggested trying 10-40 oil, I did , no help,.......anyone have advice ?

 

Is it the stock pickup tube for the oil pump and is it positioned to sit all the way down at the bottom of the oil pan? To me it sounds like when hill climbing the oil goes to the back of the pan which allows air to be drawn into the oil pump.