What is the newest engine I can drop in my 2004 f150?
Putting a newer engine in your truck will be expensive as it will also need the correct ECU, wiring harness and exhaust system and possibly the transmission as well in order to work properly. The 6.2 liter engine would give you a lot of power. If you could get a complete running donor truck it probably would be possible but would be a lot of work.
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