Lifter replacement 5.4L

I must mention that engines with the DOHC emblem had a problem with "Cam Phasers". These would rattle and knock very similar to a Diesel and the noise would fade at about 2000RPM.

This engine has 2 timing chains. Since the Camshafts are on top, the lifters are under the cam. You would need to remove the cam to access the lifters. You will need to keep the cam gear positioned or lose the mark. There are cheater tools which allow you to sneak the cam gear away from the head to change the Cam phasers.

The cam phasers can then be removed. This is perhaps as much as you need done. I retired before this style of engine was built, so I can not tell you if the Camshafts can slide forward to be removed once you remove the Phasers and gear. Otherwise you are looking at a full frontal disassembly, just the Cam Phasers alone required full frontal disassembly in the original Service Manual.

You can read more about this engine and find Videos on the Web. I have an Engineering print but an assembled engine may have clearance issues. Wish I could be of more help, but you can get quite a rattle from the Phaser issues. Don't blame the wrong part.