I get the warranty concerns. I've already got concerns since I went with the RC 1.5" front level and RC 3.5" UCA's. It really depends on the dealership and how they want to handle warranty stuff. Obviously I would never expect or try to get the dealership to warranty the changes made to the front suspension, but there is the possibility they could try to wipe out most if not all of the factory warranty upon seeing I have the front level/UCA's AND bigger new tires (34x11.5) and -13 offset 18x9 aftermarket wheels.
I will have a free oil change coming up at any GM dealership (first oil change is free with these trucks - pretty common). I am not sure I want to even chance them seeing the front level and tire/wheel changes and then noting it in their system, flagging my truck to be voided on warranty.
I am not too concerned about just a muffler swap, I think the only thing they could say with that is that obviously the new muffler isn't going to be covered. But again, you never know, they might use ANY change from stock to void a bunch of stuff.
It's a valid concern, for sure. And for the first time ever I bought an extended warranty - 5 years 100K miles - on bumper to bumper on the whole truck. It cost me 3 grand to do that, and the main reason I did was the emissions system error problems on my 2020 AT4 3.0 diesel that they never could get figured out or fixed and also would not cover under factory warranty, which I feel was BS.
I can, at any time, get a pro-rated refund on the extended warranty I bought. So at this point I'd probably get about $2900 back in a check if I change my mind on that extended warranty. I have always scoffed at these extended warranties offerend when buying a new truck, but this time was different given my issues I dealt with. Thing is, there is NO guaranteed even the extended warranty would not possibly be voided, or partially voided, given the (rather minor) changes I have made to the truck. Insurance companies always look for a way out of paying out...
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