Will a 5.4 out of a 04 Excursion go into a 03 F-150
The 03 is probably a 2V engine and the 04 would be a 3V engine which would not be compatible with the 03 ECU. It might be possible if you also swap the ECU and wiring harness but no guarantees. The transmission comparability with the ECU is probably also an issue.
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