Sorry, but I disagree with the above. Years ago this was the case and if you returned your vehicle to the stock factory tune before taking it in for service there was no issue. I know for a fact that today both GM and Ford can tell if the ECU has been flashed, when it was flashed (the last 3 or 4 times) and if it was a factory equipment that did it or other equipment (look up CRC check). If the there were modifications to the ECU and there is an engine failure, the OEM will deny the warranty repair on the engine. Same with transmission or any other component that was modified either physically or electronically.
I see your point, and if that’s been your experience with your local dealers then that sucks man! But I don’t completely agree that a tune will void a warranty just because the dealer puts in the system it’s modified.
Using your engine failure example. Yes, if you throw a rod out the block running a high power tune, they have a strong case for denial. (BTW to throw a rod out the side of a gen 2 ecoboost you’d probably have to be pushing north or 550 WHP before that became a concern, Which requires a e30 tune at a minimum)
But anyways. Lets say your cam phasers fail while your tuned. There is plenty of documented issues on stock vehicles. Tuning would not cause cam phaser failure. This is a warranty claim that would not be denied because of tuning.
My repsonse to the OP about getting a tune was suggesting a transmission only tune or a moderate pump gas tune. Neither of which are going to give him warranty issues if he has a good dealer. If he is looking for drivability improvement, nothing will make a bigger difference than a good tune. But to the OP, if your going to buy an extended warranty or aftermarket warranty, read up on the requirements to maintain said warranty.
For what it’s worth, been taking tuned vehicles in for warranty work for years and never had an issue. Everything from misfires to turbo issues to transmission concerns on both fords and rams. All of which were tuned. It comes down to the relationship with your dealer in my experience. I live in a rural area where lots of vehicles are modified to some extent so maybe the dealers around here just cater better.
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