Posting this for a friend. He has a 2010 F-150 5.4 liter with about 100,000 miles on it. He bought it used several months ago, so previous maintenance history isn't known. A little while back he started to notice what he called a pinging sound somewhere between 1500 and 2000 rpm that seemed to correspond with the transmission shifting. He took it to transmission shop and they said transmission ok, but the engine had a problem. He took it to local shop that has a pretty good reputation. They said he needed a new motor. They said an aluminum plate on the oil pump has been flexing causing oil starvation issues that have ruined the motor. I took a listen to it, the motor has a loud knock at startup that quiets a little bit after it runs for a while, but is still very pronounced. The valvetrain seems a little noisy, but the knock is way more pronounced when you listen to the underside of the engine. He said this knock has been getting worse over the last few days and he is not driving it any longer.
This is a very nice truck, but with a bad engine it becomes very expensive yard art. I am not sure how much work he wants to put into it, but I was thinking the oil filter should be cut open to look for metal shavings. If the oil filter looks good, then maybe start tearing stuff apart from there. I am thinking if it is actual rod knock, or main bearing issue from oil starvation there should be metal shavings in the filter. Does this sound reasonable, or are there some other known issues with the 5.4?