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For the 6.4 this answer is easy. You want OEM oil and fuel filters. Both are patented and aftermarket filters will not be equal. OEM means made by Racor, and will be Motorcraft, International, or Racor labeled.
Air filter probably is not as important, maybe, but I would stick with the OEM regardless.
You need to stick with OEM. There have been reports of those that tried aftermarket oil filter that did not fit. There off brand filters required a new cap and because of this it was not seating properly, starving the motor of oil.
Be very careful that whatever you choose it is identical. Best bet and safest bet is OEM for both fuel and oil.
Tip, use new motor oil for the o-rings before screwing the cap down.
There was some posts either here or in the 5.4 forum about Fram filters coming apart and blocking oil passages. A friend researched this. Without getting into a long write up, stick with Motorcraft, Wix or Purolator. Best, CB