I dont think anyone ever said that a tune WOULD NOT void your warranty , but you do want to do what you can to lesson the chance of the tune causing a warranty issue
Dont leave the flasher in the car , dont put the SCT sticker on the car , dont leave tuner box in the car , remove the tune before taking your car to Ford , , dont have a strategy your car may not of come with
Doing the things above you can lower the chance of a tune voiding your warranty to a very very small % , I have been tuning cars for 20 years and I have never had a customer have his warranty canceled from a tune
You have a much much higher chance of a canceled warranty from a air intake / header / exh etc
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