Hi Noobie here (silent member since 2017).

I have 2005 FXT with bad EJ257 (not turning by hand ). Fooling around with open-ended third car problems consistently is given low priority on honey-do list, and so rebuild likely to take weeks. BUT I have a EJ253 still running great in otherwise expendable 2005 LOB.

I'd like to use the "3" as a placeholder until I rebuild the "7." Have all accessories, etc. for both, and therefore no need to commingle any parts (both are EAT). I'm hoping that this will be a direct swap. Do I need to change out ECM's? What other things am I likely to encounter? Harness/connector issues? How can I make definitive verification that the replacement will slide right in?

I will visibly block off FXT hood scoop with "temporarily out of service" tape through the transplant period, so as not to imply any turbo activity.

Thanks for the help.

CORRECTION

The FXT engine is EJ255. Thanks.