Unfortunately you won’t find a straight forward response. My understanding is if the dealer wants to dig, they’ll be able to figure out whether you’ve used a piggyback or not. It’s at their discretion whether they want to dig deep into it. With regard to warranty, if the dealer can prove that an aftermarket product DIRECTLY caused something in the car to malfunction, they can void the warranty for that specific component of the car; it does not void all warranty. I’m curious to see- of the people that decided to add a Dinan piggyback, how many have had issues that were the DIRECT result of adding said piggyback, and whether their warranty claim was voided. I’d think the number is low, but who knows. As someone has said in another post: you gotta pay to play. I don’t know if the risk is worth the little gain