We'd probably give you the benefit of the doubt in either case, though if flashing back to stock did not fix the problem, you may want to at least attempt to reload whatever 5-Star tune you were running at the time.I'll give you a scenario. Driving along truck starts to make less power/ noise/ what ever, check engine light comes on... you check code and its XXX code. (assuming there is not oil all over the ground and a piston hanging out) not knowing what might cause it. you flash it back to stock and no change in the power/noise/light comes back on. you take to dealer and that say its an engine problem/what ever/ and want to tear in apart... so you call stage 3 and say here is the deal its at the dealer and they want me to ok the engine internal inspection blah blah blah. you say ok do what you need to and they say bend rod/piston breakage/what ever. Ford fixes and life goes on
ford says you have had tuner blah blah blah and you say "well yes but it has a warranty" proceed with the claim to stage3/5* and they check your ecu and its stock. What i'm getting at and not implying is who is to say they don't just decline their warranty because no loaded 5* tune at that time... just wondering the rules that go along with the warranty because I would like to get tuned and get a warranty and IF in the horrible case it comes into play and its used the warranty works the way it should and its not like so many of the warranty that are sold and never pay out when they are supposed to.
Only if you believe something catastrophic has happened. For general work/maintenance at your dealer, you should return the truck to stock to avoid getting your device locked out of your PCM (assuming your mods don't preclude that in some fashion).So, contrary to what we are generally told, if we have 5* with the warranty, do not return to stock. Interesting. I'm glad I saw this thread. I would have thought to certainly attempt a return to stock.
Like we said, if your motor does let go, you may not be able to return to stock due to the extent of the damage. Not to mention, we want a serious engine failure situation to look as least shady as possible when you bring the truck into your service center of choice.